BIOLR Lecture Notes PDF

BIOLOGY NATURAL HISTORY: The course is about plants and animals! It is about the observation of living plants and animals, flora and fauna and their interactions. It is an observational science. - Natural history is a naturalist - Charles Darwin is the world's greatest naturalist of all time Component 1: How plants and animals defend themselves Component 2: How plants and animals survive cold and heat, stresses in the environment Component 3: How plants and animals acquire nutrition Component 4: How plants and animals reproduce Component 5: How plants and animals get offspring to a good start LECTURE 1: Component 1: Staying Alive- Defence Appearance - Camouflage= concealment - Animals hide through the use of camouflage - Theres lots out there out of sight or well hidden - Each habit offers difference challengers for concealment - Fields and meadows have grasses and tall stems - Lots of vertical lines - (Savannah) Sparrows tend to live in grassy areas or bushy areas - Birds that are near the ground and in areas with lots of vertical lines, the sparrows themselves have vertical lines - Cattail marshes - American bittern, when frightened it points its bill in the air and whole bird shape become a vertical lione, lines on breast are vertical - Background matching, patterns on thebody that match the patterns around - Forests, leaves overhead, shades not perfect with spots of lights coming through the ;eaves - Light-dappled forest floor (light and dark spots) on forest floor - Ruffed grouse, nests and lives on floor - Female grouse nest on ground and have patterns of camouflage - Have light and dark areas and blotches on plumage - They blen - d in with light and dark on forest floor - Spruce grouse - Females have a similar pattern to the rough grouse - Its not just the pattern but the colours are earth tones with the background - Theses patterns only work if animal is motionless - Camouflage only works if you dont move, cryptic for it to work - Everything can be in camouflage, the brown creeper matches with tree bark - Gray tree frog, can camouflage with multiple colours, background matching - Mimicry - mimicking something, looking like something else - Looks like bark so its bark mimicry - Eastern screech oil has colour and patterns that match on the tree - When they are sleepy the eyes are closed and unnoticeable - Background matching, looks like bark - Hyphen between screech and owl bc they are both capitalized: Easter Screech-Owl - There can be background matching in winter - Snowshoe hair, brown in summer also called varying hairs turn white for the winter - This is called seasonal background matching, seasonal colour change - The colour white offers more protection visually and protection from the cold - Red eye verio, colour patterns can enhance concealment - Its not just one solid colour but discrete lines - Black and white warber - Chipping sparrow - Line that goes through eye is eyeline and stripe above eye, wide one called eyestripe - Many songbirds have an eyeline and eyestripe - This creates a camouflage - Breaks up the shape of the head into segment - Their purpose is to visually shape up the break of the bird to help the body vanish by becoming segments not one solid shape - Disruptive patterns LECTURE 2: - The highway is breaking the damns - Beavers are storing food for the winter - Before sunrise, broad wing hawk sitting on the tree - Sharp-shined hawk, autumn meadow hawk, behind the beaver dams - Clouded sulphur, yellow butterfly, birds food trefoil - Flower fly looks like a wasp - Background matching, other forms of camouflage and combine with background matching - Disruptive patterns so it doesn't move - Angle-winged butterfly - Masquerade: where the body resembles part of the environment - Dead leaf mimicry - Butterfly, shape is like a dead leaf, masquerade is the shape of it - Inchworm - Masquerade, twig mimicry: looks like something else - If its barks its bark mimicry - Walking stick-twig mimicry - Treehopper, a group comes in many different shapes - Thorn mimic - Many animals use a form of camouflage that involves a shape of their body that resembles something in the environment around them that is not edible - Parasitic fungus inside it making it stuck to the leaf - You find the inedible tree on a tree - Bird droppings, bird poop - Most animals don't eat it, animals that look like bird poop - Viceroy buttery caterpillar, shiny and is like runny poop left by a bird - Bird poop mimic - Moth- party wood nymph, moths can look like bird-dropping mimic - Giant Swallowtail - The biggest butterfly in Canada, giant swallowtail - Caterpillar feeds on pine needles - Imperial moth caterpillar - Pine cone mimic, big a hard, little white dots like resin dots - (his theory) - If a parasitoid lays its egg on the caterpillar, another form of defence (ignore) - Adding bits of the environment to the body is another form of camouflage- like adding flowers stuck to it, a caterpillar can do this - Camouflaged looper - Hiding can be inside a structure - Spit, animal sucks sap and the back end adds air jet coming out making it into foam as the insect hides and feeds - The spittlebug looks like spit! - True bugs are different, have a mouth part that pierces something - Frog hoppers, adult spittlebug - Colony of animals, woolly aphids that create wool - Aphids are bugs, built excess liquid front their back end - Larval foams - Carpenter ants are bodyguards - Scarlet lily leaf beetle eats lilies - They have a membrane around them, when they poop it builds around them and becomes a poop - Scarlet lily leaf beetle larvae - How do animals in water gain defence - Beetles are on top of water, in groups that swirl around in the water - Whirligig beetles, whirl around - They are dark on the top and light on the bottom - Bicolouration: offers background matching in two directions - Blend in from two different directions based on point of view - Background matching - One group of aquatic insects has a dark underside and a light upper surface - Squirrel family, carnivores, dog family - All animals have groups - Maladaptive- discolouration - This insect swims upside down on the surface called Backswimmer - It makes them hard to see, like a bird looking down or a fish looking up - White-tailed deer are also dark above and light below - If they stand still and the sun shines down the belly is shaded by the upper part - Makes it uniform in colouration - If it has a contrasting part to the body it makes it three-dimensional (easier to see) - Countershading(not the same as bicolouration) - Self-shadow concealment - Why so many larger animals, mammals and birds have darl above and light below - Wolves - Hairs (bunny) - Sandpipers (bird) - What if the moth camouflage fails, they employ plan B (when necessary) - Open the wings, bright colours appear - The sudden appearance of bright colours may startle the animals that trying to attack it - The moth can fly away briefly or fly somewhere - Underwing Moth - Catacola - Species are grouped into genera, family genus and species - Greek for beautiful behind - Darling underwing, startle patterns - Startle attacker while moth flys behind a tree for safety - Wood peckker that drills holes to get sap - Morning cloak butterfly - European hornet (very big) - Flew towards this and scared away the hummingbirds - Ultraviolet patterns in flowers - Caroline locust, wings are beautiful bright colours - Grasshoppers can have startle patterns - Sphinx moths- underwings wings they have startle battens - One eyes sphinx has eye spots - Hawk moths have eye spots - Blinded sphinx - Underwings have startle patterns - Polyphemus - Has incredible eyespots - They are hidden until needed - Io moth - Gray tree frogs, climb trees and they can change their colour to match better - When it jumps, bright yellow patterns on the hind legs - Rig neck snake- yellow - Red-bellied snake- orange - The second defence what appears to be snake tongue, a terrible odour - Osmetarium- startle structure - Beaver uses their tale to make a startling effect, slapping their tale - Startle Sound - Rough grouse - Take off with an explosion of wing sound - Make startle sounds - Eye spots visible all the time help it survive for a longer time - Eyed Elater - Tiger swallowtail caterpillar (eastern) - Common Green Darner - Eyespots make animals look large so that their life - Startle patterns can have a 2nd function - Distraction patterns - They can deflect a predator attack (to a non-vital body part) - Some butterflies have tails - Hairstreak (striped) - Bandedm Acadian hairstreak - Eastern tailed blue - Tails can look like a head - Autotomy is the ability to regrow a body part - Physical defence can consist of body armor LECTURE 3: - distratcion or deflectio strcutures- patterns of colour or form that make the predator’s attack deflected to a non vital body part. - because tha other animal and sees tge structure and thinks its the head, it distracts and deflects the attack - eastern tent caterpillar silk tent - the caterpillars build a silk tent and stay inside their tent for safety and leave when its safer , to eat. - fall webworms also make a silk tent but their tents are different… esastern tent caterpillar tents are in a fork in a shrub and there are no leaves inside it and they leave at night to eat… with fall webworms they build their tents around the leaves and so their food will be inside their tent so they dont need to leave for food. - caterpillars have soft hairs for physical defenses because eating hairy things isnt fun, so it deters some predators. - the caterpillars roll into a ball when under attack so all hairs stick out. - woolly bear caterpillars have hairs in the form of stiff spines. - some mammals as well also use stiff hair for defense - porcupines for example. - mammals in the wild have a lot of hair on the ouytside of the body… called guard hairs… porcupines have some guard hiars modified into Quills. the quills are hollow and the end have sharp points and they have overlapping skales so when they are embedded in an animal , as the animals muscles expand and contract around the quill tip, it makes it go further into the animal. - there are at least 20,000 quills on porcupines, but they can not throw them, there has to be physical contact between the animal and the procupine, usually it slaps the animal with their tail and the quills stick and come off into the animal readily. - porcupines can impail themselves or other porcupines. - there is a greasy coating on the quill which contain antibiotics, this might be because the antibiodics prevent infection, allowing the animla to live.. thus it learns a lesson and allows the animal to avoid porcupine in the future.. and also there is a possibility of learning as the animal will teach its offspring to stay away from porcupines, thus aiding in their survival. the second reason it might be is because porcupines often fall from trees and their porcupines might get into them, thus it could be a protection for them. - hairs and posion = poison spines … these are called chemical defenses (whenever poison is involved) - Io moth caterpillars have poison spines…. there is a small amount of chemical in them which cause a burning sensation (but wont actually harm you in any serious way) - poisonous caterpillars are usually brightly coloured because they do not want to background match, they want to show their warning signs that they are poisonous. - milkweed tussok caterpillars are poisonous - giant leapard moth caterpillars have poison spines. - yellowjacket wasps can inject a chemical which burns in their defense … this is why they are brightly coloured (to show theyre dangerous to predators). - red eft - salamander - it is brightly coloured as well because its skin contains a toxin. - milkweed beetle - stores toxins in its body. - warning colouration = aposematic colouration - many animals that have chemical defenses use aposematic colourations to warn predators not to come near. - striped skunk - have a chemical defense which they spray out their back end… - black and white colours are aposematic at night - eg. the porcupine have black and white colourations and at night this is very distinct. same with skunks. - ladybugs manufacture their toxins. - other animals attain chemicals by eating plants that contain them. for example eating milkweed leaves make the animals have cardiac glycoside posion in them which is poisonous to other animals… and in large doses it can cause heart failures in animals. - monarch caterpillars eat milkweed and thus they sequester. - **sequester** is what happens when animals eat something which makes them poisonous. - milkweed tussock moth caterpillars also sequester cardiac glycosides from milkweed. - black swallowtail caterpillars sequester toxins from water hemlock - if an animal eats a plant that has a chemical defense, and stores that chemical safely in its own body making it then unsafe to eat = sequestering. - some produce tthe chgemnicalas like the ladybugs, others get tyhem from the food they eat. - fireflies have a light organ … they also have a chemical defense which they get from their food… photuris fireflies sequester steroidal toxins by easting male photinus fireflies… but its the female photuris ones that get them… female photurus go and see if they can find male photinus’ then they will then land on the ground and blink the mating signal of the female photinus, tricking the male photinus into thinking its a mating call, when the male comes in to what it thinks is a female wanting to mate, the female then eats that male and gains the toxins from the photinus male to gain their chemical defense… this is called **aggressive mimicry.** - sawfly larvae - prolegs are little suction cups… sawflies have prolegs all the way down their body. - they blow bubbles which are terpenoids which they aquired from sequestering what they ate. - blister beetles - it has a chmeical which comes out from a leg joint - cantharidin which is a terpenoid - it sometimes plays dead. - yellowjacket - injector = stinger , injecting their chemical defense into their attacker - skunks have a sulfur alcohol defense. - they try not to spray because it is costly to make.. spo they trty and scare off animals first. - the bombardier beetle - shoots out chemicals out the backend which buirn.. a burning cloud of chemical defenses which are super hot quonine gasses… the components in its back end are stored seperately to not hurt the animal, and when under attack it shoots both out which mix together and burns. - animals armed with chemical weapons often bear aposematic colouration… aposometic colouration allows a predator to learn to avoid them. - a bumble bee also has aposematic colouration - when a group of **unrelated animals** are all defended and bear similar appeareneces = mullerian mimicry … becayuse trhey are resembling each other (for example wasps and bumblebees… also milkweed beetle and milkweed bugs) - family = groups of animals that are in some way related to each other - true bugs are insects with sucky mouth parts… mosquito dont live on blood they get blood for their eggs. - when monarch caterpillars change into the butterfly, the toxins go into the body of the butterfly - most viceroys are okay to eat, most monarchs are bad to eat… viceroys look like monarchs so animals likely do not eat viceroys if they are familiar with the toxicity of monarchs…. this mimicry where a harmless animal resembles a toxic animal is called batesian mimicry… the poisonous is called the model and the safe one is called the mimic. - bubble bee stings and hover fly harmless (batesian mimicry) - honeybee stings and hover fly harmless (batesian mimicry) - bald faced hornet stings and hover fly harmless (batesian mimicry) - hover flys (AKA flower flys) have wings which appear to have two sets of wings through the colours, because flys have one set of wings and wasps have 2. - wasps have 2 pairs of wings, flys have 1 pair of wings… wasps have long antenna, flys have short anttena. - wasps have many mimics - flower flies, dragonflys, moths (raspberry crown borer), beetles … so many mimics! - for the system to work of batesian mimicry.. there must be more models than mimics, and also they must occur at the same time of year. - american toads have the toxins in their skin… bufotalin in skin glands. they also have a second defense… a behavioural defense. - when american toads are alarmed they can fill themselves with air and puff themselves up to look like a larger animal. - hog nosed snakes also puff up by taking in air and puffing their heads up… - if plan A (bluffing) does not work, they play dead. some animals havbe an aversion to dead snakes… a lot of animals want live prey or just to kill the snake. - playing dead is called thanatosis. - hog nosed snakes can puncture the skin of the toads to deflate them, and the toxins of this toad dont bother them. - puffing up is called bluffing. - some blister beetles also play dead … thanatosis. - virginia opposums also play dead. - behavioural group defense - in winter, white tailed deer gather in very large numbers - called a yard. - safety in numbers - deer for large groups for the winter to raise their young - flocking is a bird group defence - flocking might serve to ; - visually confuse predators - for each flock member, lower yhe odds of capture (safety in numbers) - a collection of starlings are called murmeration. - flocks are very common in migration because the birds are facing more danger - group defence can be aggressive - in yellowjacket wasps, they release a chemical called attack pheromones when noticing danger, this causes the other yellowjacket wasps to get angry and violent and excited. - bird behaviour defenses can also be aggressive - kingbirds are very small but fearless.. they are very aggressive and attack if an animal goes near their nesting areas. - chickadees can use alarm calls which tells other chickadees there is a danger (usually an owl which attacks at night) and thus the pther chickadees can come in and make the owl or animal leave the area so that it wont attack at night. - mobbing is a pre emptive defense - trtying to avoid what looks like a danger and thus calls on other animals to swarma and attack animal to get it to leave. LECTURE 4: - alarm calls can summon other birds to join attack (not just same species —- eg. chickadee, blue jay, etc so that they can all avoid the possible danger such as the owl) - a pre emptive defence because its done before an actual attack occurs - barred owl- pretty common in our area - some animals have bodyguards - carpenter ants guardging aphids - because the ants eat honeydew which the aphids make… and thus the ants protect them. - oleander aphids do not use ants as bodyguards because they have chemicals inside of them because they are feeding on milkweed… thus they have aposomatic colouration. - some behavioural defences seem odd - when alarmed, the cotton tail rabbits run and show off their white tail, it may seem obvious since it is very bright and easy to see… same with white tailed dear…. - this is because maybe ; - warning other deer of danger - white tail is being raised to show the predator that i sees you, and knows youre chasing me.. its not a surprise attack and i will get away. - cotton tail and white tail both jump around when running away and run erraticly… and a theory is that if the predatror stares at these bright white tails, they might get confused or stop paying attention to surroundings and trip on something. - these are called flags since they only show up when being chased or in danger… which might advertize awareness or distract it. - vigilance = being alert and scanning for danger.. 3 scanners for mammals; - auditory ; ears - visual; eyes - oflactory ; nose - large ears capture sound - many can also can pivot these ears to scan in different directions - moose antlers can also be used for hearing… pointing ears toward curved part of antlers acts as an amplifier. - beavers have small ears because beavers swim … thus if they had big ears it would be harder to swim. - some non mammals have “ears” which are special membranes on a certain part of the body which can detect sound - some moths have ears which are a membrane on thorax - others have ears at the base of their wings. - a number of insects have membranes for picking up vibrations of sound. - some animals dont have ears. - for example, snakes cant hear… but they can sense vibrations. - snakes also have an enhanced power of smell / taste - these have fork tongues because they pick of the molecules of sent carried by the air, and the snakes put these molecules into their “jacobsons organ” which has two pockets and it analyses the scents. - moose have excellent hearing but they also have an excellent olfactory sense - sense of smell. - an enlarged snout houses more sensory cells and a jacobsons organ - mammals expose the jacobsons organ by flemen… - exposing the upper surface of the mouth by opening the mouth and curling up the lip to give a bigger area for the organ to analyse. - scanning visually; - snowshoe hare… eyes on side of head which provide larger view of the surroundings. - each eye has a field of view and see all around withouyt moving its head. - same with mallard (duck) - two fields of view, one from each eye… total field of view = 360 degrees which allow for seeing in front and behind them wiuthouy moving… eyes on the side make the view wide. - owls have the eyes on the front. - owls thus have obstructed view on back - animals that hunt tend to have eyes to front whcih give more binocular vision which allows depth of field. - beavers have a nose, eyes and ears on top of head like a crocodile… - thus all of its sensory organs are on the top of its head and it can almost be fully submerged ion water. - the eyes of a wilsons snipe (bird) are on the upper rear of its head. - sanpipers feed by sticking their head in mud thus they have their eyes much back so that it can see when its feeding.. this view gives more depth of view behind the head. - when alarmed, an american bittern puts bill in air and freezes (backgrounbd matching)… and where their eyes are (near the base of the bill) allow them to see forward when their bills are up. - no adaptation is perfect. - eyer placement tells a lot aboyt animal… eyes in front = hunter, eyes in side = prey. - night active animals … the larger the eye the more light it gathers, thus night active animals have larger eyes. - flying squirrels have this feature. - if you shine a light in night active animal’s eyes, a colour reflects…. this is called eyeshine… this is bceause if light comes through the eye in wavelengths, if any misses the sensory cells in the back of the eye, by being reflected forward again it gives the eye a second chance to be able to pick up a missed wavelength of light.. thus giving them an enhanced ability to decet small amount sof light at night… ythios reflective area is called tapetum lucidum. - eyeshine might be red, green, white. - more eyes allows for more ocmplete vigilance (more vigilance in numbers… another reason why white tailed deer yard in winter… and also why birds flock in spring and fall) - (flocking = more eyes = more vigilance) - two types of flocks - flocks where birds are all same species (single species flock) - waxwings use single speciies flocks - flocks where birds are a mix of speices (mixed species flock) - different species of warblers flock together. - the differences in flocks lie in the food resource types - warblers eat specieis - if you have a group of birds where the food reseources are scattered and they vary in their location or type or both.. the birds who specialize in different food they dont compete for resources…. if they used the same feeding, they would be competing for resources. but, if youre feeding on fruit as the wawings do, and you go to trees there may be a lot of fruit and thus you can travel together since there is no competition of resources. - thus birds who feed on fruit will usually use same species flock due to fruit usuaklly being a vast resource which is not limited. - seeds can also be in large quantities… large pinecones have seeds inside pinecones… some birds are specialized to eat them, crossbills are a type of finch which eat seeds and therefore the birds which feed on seeds likley will use same species flock since seeds are another vast resource. - other birds are mixed speicies flocks because the food they are going after are in small quantities and not all together.. in different locations. - benefits of both flock types are more eyes to watch out for danger. - plants are constantly under attack by anything from large animals to small insects. - every part of a plant can be food for different animals. - but there can be many excess of plants… why? because they use defenses! - constantly changes in the chemistry and the physiology of the plants to get stronger … evolution. - physical defenses - trees and other woody plants have external **armour …** trees have bark! - seeds can be protected inside hard coats. - acorns have extremely tough coats… similar to turtle shells! - no defense is perfect! some aninals can get through the hard armour. - thistles have **spines**… spines are modified leaves which are modified into really sharp points. they are more defensive structures against larger animals… but **prickles** are epidermal outgrowths, like hairs, which can be for smaller animals. - some shrubs / trees can have hawthorns which have **thorns** which are modified branches or stems. - prickly ash has either thorns or prickles —- not sure. - a lot of defenses are analgous to animal defenses — for example thorns on trees are modified branches and quills on porcupines are modified hairs… thus these are analgous. - these structures do work… they hurt the animals! - plant hairs are called trichomes… kind of like the soft hairs on the caterpillrs which make them less appealing / edible. - mullein leaves are largge and very fuzzy… this is because they are covered in the little defensive hairs - trichomes. - some trichomes have balls on the end and some dont - stinging nettles burns… some of the trichomes have balls which are loaded with chemicals that when contacted with them get injected into you and burn… these chemicals are in the glandular trichomes whichg are physical and chemical defenses. - water smartweed grows in the water and in water they are relatively safe from animals so they dont have trichomes… but if the water dries out.. they grow tricghomes! these are called inducible since they are grown on demand. LECTURE 5: - internal structures can serve as a deterrent as well - structural elements such as **cellulose, hemicellulose and pectin** mmake plant tissues hard to digest. - lignin gives leaves stiffness, nuts and cherry pits their hardness. - silica is found in horsetails (plant) - silica is a very tough material found in glass. - grasses are also full of silica… very tough because of silica.. - structural elemnts like cellulose, hemicellulose, pectin and silica are called digestibility reducers because they make it hard for animals to digest them. - other digestibility reducers are not structural components, they are astringent.. they are called tannins. - becasue they have another purpose in the plant they are called secondary compounds. - calcium is also used as a deterrent… arum plants have crystals inside their leaf tissues made from calcium oxalate which burnb lips and tongues and make it very hard to digest. - arum plants have calcium oxalate crystals in their leaves. - they start the winter in a bud stage and then they generate heat melting the snow around them. - jack in the pulpit is also called an arum, which have crystals in their tissues made from calcium oxalate and they burn lips and tongues and can cause problems internally if swallowed… makinf them a deterrent. - milkweeds contain a chemical called terpenoids… terpenoids are not deadly but the one in milkweed are cardiac glycosides which in large amounts can cause cardiac arrest, but the main thing is that they are very bitter which deterrs predators. - terpenoids are more a repelant because of the biterness. - terpenoids do not contain nitrogen - terpenoids are a major group of plant chemical toxins… monarchs have evolved in eating the plant and storing the chemicals in their bodies. - new pine cones have resin… resin contains terpenoids. they are found in coniferous trees in the new cones. - another plant defended by terpenoids is poison ivy… it has resin. - asters contain chemicals that contain nitrogen… they are called alkaloids. - alkaloids contain nitrogen and can be very nasty inside the animal. - buttercups also contain alkaloids. - some alkaloids are sugar mimics. alkaloids interfere with digestion by binding to an animal’s digestive enzymes and thus the animal cannot digest the food properly which can cause serious consequences… proteins and other enzymes have nitrogen in them which is why these can bind to the enzymes. these are constitutive defences… this means that these defenses are always in the plant. - other toxins are produced on demand… when an animal bites into the leaves of certain plants, the components are there and they mix whgen the animal bites into them and thus the hydrogen cyanide is inducible… for example black cherry’s use this induced chemical defense. thus alkaloids cause problems of digestion - bracken also contains hydrogen cyanide. - some chemicals disrupt digestion by interfering with digestive proteins such as proteinase. - potato plant… has alkaloids that if eaten by the potato beetles, it effects their digestive system… so proetinase inhibitors prevent proteinase from doing its job. - a wounded leaf sends out wound hormones and other parts of the plant then can start preparing for the attack. - some plants produce insect growth hormones. - moulting hormone (ecdysone) - tells it to shed its skin to the next stage - juvenille hormone - keeps it in juvinlle stage - mixture of both hormones in early growth larva stage 1 and 2, and in the third stage no JH - early stages it has MH which allows it to shed its outter skin, and juvenille horomone still keps it in the caterpillar stage, and then in the third stage the JH is no longer there and thus it allows it to start going into its pupa stage where it can go thropugh transformation to butterfly/ moth. - many ferns are loaded with moulting hormones. - because they are produced by the plant they are called phyto ecdysones. - bracken fern is also loaded with phyto ecdysones - these MH make insects mature too quickly and die. - when they keep eating the MH from the fern without JH, they make the animal moult too often too quickly and causes premature death. - balsam fir contained phytojuvenile hormone… so if an insect eats it, they will never mature… they cannot pupate and they cannot become adults. - these chemicals are mimics of hormones in animals (primarily insects) - some plants produce hormones that animals use in their growth development period, and because they are perfect mimics they are called phyto phytomolton and phytojuvenile. - reproductive hormones are also used - some plants produce phytoestrogens which mess up an animal’s reproductive system. - this can cause spontaneous abortions and other wrong things can happen in the female reproductive systems. - phototoxins - very nasty side effects — toxins migrate next to the skin or exoskeleten, making them very susceptible to sunburn which can cause sores which can get infected and poissbly cause death. - st johns - wort is an example of a plant with phototoxins. - mustards advertize their defense - bright yellow colour and even their odours to say theyre armed with a chemical defense - plants use aposematic colours too… blueberries use warning colouration until the terpenoids are neutralized when it becomes ripe and blue. - when an animal eats blueberries they poop out the seeds which plant them somwhere else. - when a plant is under attack, an alarm is sent to other parts to prepare themselves. - chemical messengers = phytohormpnes which travel through the plant initiating biochemical responses. challenge #2 - environmental stress - temperature extremes - sub zero temperatures - water turns to ice which is a problem because ice expands.. and all animals have water inside their systems and if water freezes, it expands which causes problems. - ectothemrs (the outside temp effects their internal body temp) - endotherms (can generate own heat) - solution A; dress for the occasion - mammals grow more hair for the winter… guard hairs (outter hairs) grow longer and thicjer for the winter. those coyrse hairs help trap more body eat… they also have underfur underneath the guard fur next to the skin, is a wooly dense fur which traps even more heat. - birds grow bulkier feathers. - gray jay / canada jay grow bulkier feathers. - contour feathers on the outside grow bulkier in fall for winter, and dense down feathers underneath… like the black capped chickadee. - animals also add extra layers on the inside… mammals have two types of fat - subcutaneous fat for insulation = warmth - internal brown fat for burning for warmth …. when you iuse up fat inside the body it is metabolized to use for various functions and when it is metabolized it generates heat. - birds do not have brown fat. - birds add subcutaneous fat for fuel - muscles for flight require fuel so they shivver at night, their muscles are moving and thety are burning up the fat and generating heat. the creation of heat is thermogenesis which is done by shivering. - colour can provide warmth. - white is warmer - pale colours retain body heat better… dark colours have pigmentation in little hollow vacuoles insiede the hair or feathers, which majkes that strcuture more solid which can let heat go through or absorb heat and it can also lose heat… but when they are white they have nothing inside but air… these hold body heat in better. - gloger’s rule - animals in the far north are lighter in colour than animals in south. - animals tend to be paler in the north because its a warmer colouratyion. - snowshoe hares gain 27% in the coat’s insulation value by being white. - the more northern deer are carribous, short extremities (tails, ears etc.) are better in colder places because extremities lose heat more readily since they have a lighter mass (just like our hands)… this is called allens rule (shortr extremities are better for colder pklaces) - low surface area volume ratio - if you have a large surface area and a small volume = high SA to V ratio… if you have low surface area and high volume this is a low SA to V ratio which is better because you lose less heat. - want a kow SA to V ratio; close to 1;1 ratio (for example 100 SA to 90 V is close to 1;1 which is very good)… This is called Bergmann’s Rule. - soiuther fox and norther fox… northern fox do hagve big tail because they wrap their tail around their head when sleeping since it has thick fur. - short tail, short ear, more round is very good for Bergmanns rule. like a meadow vale. - ducks, seagulls, muscrats, swan etc. stand on ice / swim in water without fur… this is because they have a specific structure at the top of their legs which exchange heat between arteries and veins, and thus the heat from the artery is passed to the veinous blood going to the heart, and thus the artery blood going down to the foot is cool, and thus since they have cold feet they dont lose much heat to be lost to the environment… this is a countercurrent heat exchanger … and called rete mirabile or wonderful net. the wonderful net can be activated or bypassed… thus in summer they want to lose heat through feet and the arteries and veins dont exchange heat, they go straight down and up isntead of being wrapped around and branched with each other like in winter / cold weather… this wonderful net can also be found in base of tails as well. - colour, body size, extremity size and rete mirabile. LECTURE 6: - rete mirabile or wonderful net - countercurrent heat exchanger. - the warmer the feet would be to the colder air, there would be more heat lost, due to a gradient, that has to be replaced by the body, so by lowering the temp of the foot that means that there is less energy needed to replace the lossed heat beacuse the heat loss is a lot less by having a cold foot in a cold environment. - there are pther ways to conserve energy too - if youc conserve body heat then you conserve energy because it costs energy to replace the body heat… for example, how an animal breathes can also conserve heat and energy. - An animal like the fox breathes through the nose and in the snout are counter-current vessels and that means that the warm blood can be passed to the blood carrying the material (like oxygen) back into the body warming the air to go to the lunges…. thus some animals use this to warm them - where a bird roosts is important - roost = spend the night - if a bird spends a night in winter they usually will spend the night in a coniferous tree because it keeps its tree needles through the winter. even better is a coniferous tree covered in snow. - conifers covered in snow = better roost site. - some birds sleep inside cavities. - less wind and also the cavity around them tends to hold their body heat better - woodpeckers roost in winter their nights inside a cavity - small owls can also sleep in cavities. - and even black-capped chickadees can sleep inside cavities - some small animals especially mammals will sleep in cavities too, like flying squirrels, but they wont do it alone, they will all will **huddle** in the cavities to share their body heat together. - raccoons too can stay in cavities in groups. - thus tree cavities can be an important site in winter for animals. - some animals build their own shelters - snow-covered shelter - called a den - muskrat lodge - house made in habitat by muscrats and they stay inside a lodge. - they use plant fibres, especially cat tails - beavers also built lodges - beavers add a lot of sticks to their lodge and they are bigger structures - lodges and dams are not the same… dams hold the water back, and a lodge is a structure that beavers sleep in. - a sign that the lodge is still active, you tend to see trails through vegetation where beavers are dragging materials, also you see newer materials added to the lodge. - beavers often do a double carry - they hold mud with their forearms and have sticks in tehir mouths to add as well, - beavers add mud for insolation, keeps more body heat inside the lodge. - as winter comes in, snow helps insulate the lodge. beavers do not hiberate and thus they need to breathe and get in and out of their lodge so they have chimneys as breathing holes with less mud so they can leave. but because of this hole, their smell comes out of the lodge and thus their preadtors can smell them, but this frozen mud and sticks is very hard to get through so they are pretty safe. - small animals find warmth under the snow. - a very deep thick amount of snow holds heat toward the ground and thus small animals may dig and stay underneath. - you might see tunnels when the snow starts to melt, this is because it is more crystallized. if you have a big pile of snow, down next to the ground teh weight of the snow and a lkuttle warmth from the ground is coming up and this makes the botoom of the snow pack crytsalize, and small animals can push through these ice crystals and move around.a lot of small animals stay under all this snow in this crystalized area which is called the subnivean space. - subnivean space is safer and warmer for small animals. - some birds also find warmth in the snow. - ruffed grouse - ruffed grouse dive under the snow beacuse they are too big to get to the subnivean space, and thus they dive in and make a little space and spend the night in their snow cave. they make a snow bed. - on a cold day an animal can bask in the sun - they find a sheltered spot where there is no wind and just let the sun shine on them to get their body warmer. - basking can be done while sleeping, such as small owls in a tree warming up in the day because they hunt at night. - chickadee active in winter - black capped chickadees are endothermic… and on really cold nights, chickadees can lower their body temperature by about 12 degrees celsius. at the same gtime they enter a deep sleep called torpor. - this conserves energy because they lower their gradient from insiede their body to the outside temperature and thus it takes less energy to keep tehir body at this temp. but if the body core temp drops more than 12 degrees, they have to generate more heat to bring it up (they generate heat by shivering which is an important means of thermogenesis-creating heat). - these birds are endothermic… tend to keep a fairly even temperature at a high temp - even for chickadees, if body temp is below 0 they die, because water turns to ice - watersnakes and frogs are ectotherms, there inside temp falls with their temp around them, and they survive winter by going down into the ground below the frost line (in crevases and rocks and so on) and become dormant. their dormancy is a form of behavioural freeze avoidance… they avoid freezing by this behaviour. - the area where a snake spends its winter is called a hibernaculum… lots of snakes go down into these. - all adult turtles and **most** hatchlings and most frogs escape subzero temperatures by going to the bottom of ponds and lakes, down vbelow where the ice would freeze to. - american toads dig down beneath the frost line, and so do many salamanders. - but many insects surive winter above the frost line - many dont survive subzero temps - but many ectotherms go dormant and use an antifreeze like glycerol = cryoportectant, - if you are an ectotherm and subjected to subzero temps you must use an antifreeze like glycerol to keep inside water from freezing., - insects usually overwinter in sheltered sites but some not as adults. praying mantides overwinter as eggs…. they survive winter by reproducing and leaving eggs for winter… praying mantides make egg cases to protect them called ootheca… eggs can lack antifreeze because they dont have water. - clycerol or sorbital are both cryorotectants - walking sticks also overwinter as eggs - they are layed on the ground and ants carry these eggs in their undergound chambers to spend the winter… the ants take them ebacsue the cap is edible to them, and later in the seasons the ants will eat that and throw the rest of the eggs in a garbage pile underground where they can hatch. - some insects overwinter as larvae. - woolly bear spends its winter as a catterpillar,,, and has glyzerol added to its system. - when no ice forms inside the body = supercooling. - other insects survive the winter as adults. - female mosquitoes, female wasps and female bumble bees spend the winter as adults - angle winged butterflies spend winter in the butterfly stage. - thus they have supercool - silk moths overwinter as a pupa in a caccoon - some insects spend the winter as a pupa. - stems of plant you may see a swelling of the end and this is the house for some insects overwintering… this swelling is called a gall and it is found on a goldenrod… the female fly lays an egg on the stem and then the chenicals make the stem grow around the gal and then when the fly is awake it will eat the gal and have a protective case around it… this is called a goldenrod gall fly grub. - the goldenrod gall fly is frozen but alive. theres no ice inside of the cells, but there is ice in the body… the ice forms in the space between the cells… they put antifreeze in the cells but not in the space between the cells, so in between the cells ice will form. so the cells are supercooled but there is still ice around the cells, so not completeled supercooled… thus it is called freeze tolerance. - cryoprotectants = inside the cells - ice nuleating sites = between them - freeze tolerance = ice inside animalas body but is controlled and forms only between the cells. - downywoodpeckers and black capped chickadees poke the gals to eat the grub from the goldenrod galls. - herps (herptiles- reptiles and amphibions), some avoid freezing temperatures but not all. - gray tree frogs stay near the soil’s surface and freeze! they use freeze tolerance as well. - gray tree frogs, wood frogs, spring peepers and chorus frogs all are freeze tolerant. - snapping turtles cannot supercool and are not freeze tolerant thus they need to go below the area of freezing and spend winter there. tehy use behvaioural freeze avoidance. snapping turtles often spend winter in a dormant state where a stream enters a lake because there is more oxygen. they breathe through their skin when hibernating. - snapping turtles hatch in fall. - hatchlings snapping turtles head for water where they spend winter dormant. - painted turtles also lay their eggs in the ground. - but some hatchling painted turtles stay in the ground all winter. thus painted turtles are freeze tolerant… as hatchlings only. after their first year they are no longer freeze tolerant. - fox can pull up the turtle eggs and lick out the contents. - endotherms cannot freeze but some do become dormant. - raccoons undergo periods of lethargy - lethargy = they can lower their body temp and heart rate and go in a deep sleep inside a sheltered place like a den, but they can wake up on warm days… thus this is a short sleep. - porcupines can also become lethargic. - chipmunks undergo longer periods of torpor which is called hibernation. - chipmunks sleep for several days underground, then they awaken every few days… during their sleep they have a low heartbeat, low body temperature, but they still awakebn every few days and have food and bathroom and then sleep again. this is not true hibernation but it can be a type. - bats also undergo “hiberantion” - they are usually not sleeping for whole winter, they can be earily aroused.. thus not true hibernation. - black bears have a low heartrate, but have a high body temp and are easily aroused… they spend winter in dens (can be under tree stump or under fallen tree)… thus not true hibernation. - before hibernation animals fatten up and they eat sugar rich foods like choke cherries… so do chipmunks. - bears when they climb the trees break off the branches and they eat the cherries. - they climb as high as they can and break of branches and form these tangles which are from a bear feeding and called a bears nest.. sign of bear getting food for winter. - they love nuts from american beech tree called beechnuts. and they climb beech trees to get these nuts. - still fat in spring and fat sustains them while there is not much to eat in early spring. - bears dont urinate or defecate during winter dormancy… they have a plug that froms in their rectum.. its called the tappen which keeps them from fouling the winter den. LECTURE 8: Environmental Stressors: - Major strategy for animals is to migrate to warmer temperatures - Banding, putting bands on birds legs - Red knots- endangered, travel the greatest distance for birds - Large-colourfil band with a number is important for studying - Trees exposed to sub-zero temperatures of adaptations go through a process - Cold hardiness- two stagtes - Acclimation - Ic forms between the cells, freeze-tolerant and ice hardy - Cell membrane becomes more flexible - Pytochromes detec photoperiod - Dessication is another problem - Plant exposed to subzero temps with water insider, solute lowers the freezing point and it can dry out - Calm,sunny days are the worst - Conifer trees tretant heir leaves so size and shape are very important - Spruce needs;es. Small elaf area - Pines trees have longer needles and southern - Baited trees like maples. Deciduous trees - Close stomata- pore in needles that allows ofr air and gas exchange that can be shut off - Water vaoour can pass through them - Close statmata - Thick coatings, cuticles from water breaking through them (TREES IN WINTER) - Peatland- floating, plants - Hairs on underside of leaves - Anothern peaat land, labrador t with hiars on the bottom side - Hair flows over and create barrier to help retain moisture - Break up the air flow and helps protect - - plants become cold hardy - they can survive freezing conditions - - if the leeves are still out there they take water from the leavses bfore it gets relaly cold and its evaporated so the leaves have lower water content. - - the cells are where the problem arises in plants and animals so they piull trhe water out of the clels… that increases solute concentration b eacause inside each cell of a planty tissue its not just water in there, theres all sorts of things in there such as mitochondria, nuclei, and other thinsg like sugars, and so when the water comes out, the solute (all of the things) bnecopme more concentrated and that lowers the freeing temperature, the more water there is inside the cells means that it has the water freeze at a warmer temp (still below zero), sp the more water goes out theres jore concerntation of the particles whioch lowers the freeezing temp… so thye dont add antifreeze, they take water out which increases the the concentration of particles which decreZSes the temp which the water will freezed. - - not only is water takenm out, they add sugars to that which will ioncrease solute concentration… the particles inside the cell are increased in number and in concentration. - - another feature is the cells of planst ahve a membrane aking the oiutside and this membrane becomes mnore flexible. - - the membrane beceomes more flexible and ice forms between the cells just like in animals, so if ice forms outside instead of penetrating the cells and bursting them, the membrane bends around the ice crystal thus it deflects inward to save from penetration. - - ice forms between the cells, andc inside the freezing point is lowered becewause the solute concentration increases because waters are taken out and sugars are added whcih depresses or lowers the freezing point. cold hardiness is analogous to freeze tolerance in animals. - - the plants become cold hardy through the process of acclamation which is in two stages; the first stage is triggered by a change in the photo period - the photoperiod is the ratio from light to dark…. that ratio is the photoperiod - - as you get toward autumn at the end of summer you get shorter days and longer nights so that change triggers the first stage of acclamation … the first stage of the plants preparing for sub zero temperature. - - they have special things called phytochromes that are pigments inside them which are light sensitive… they react to sunlight… they can sense the ratio change in light and dark, they can detect the photoperiod changong, and when that happens theres a chemical reaction inside of the plant which causes the cells to go dormant and it makes the plabnt more responsive to low temperatures. - - the second stage is triggered byt cold (but not sub zero) temperatures 10 degrees to 0 degrees… so the first stage is triggered by the light to darka dn the second change is triggered by being more sesnitive to colder temperatures… in the second stage it involves things like just preparing for subzero temps by takiong more water to the cells and adding more sugars to them … so in the second stage the plants are exposed to the cold condition really become more active in taking more water out and adding more sugar and the cell membrane becoming more flexible. - - some trees become cold hardy to -80 degrees C - - conifourous trees have needles and othjer trees have big leaves like maple and birch and so the trees like conifers which retain the needles theyre exposed to really cold conditions and so the chlorophyll (green materaila which plants use to manufactor food through sunlight) but in winter they dont wanna be active, so they can use the chloryphyll in their needles to absorb solar energy and generate heat, not to photosynthesize sinc ethose pathways are dormant… but they can still absorb heat by absorbing solar energy with the clorophyll - - trhe problem thats created by having the needles and the sun out there is damage by solar radiation - - they have special pigments which protect them from the sun (kinda like sunscreen) … xanthophyll pigments - - skunk cabbage has an unusal adaptation for the cold … it has buds rthat over winter under the snow where its a bit warmer… but by late winter skunk cabbage startys to generate heat and have more active metabolism inside its system, giving heat as a byproduct, and it melts the snow around there so theyre exposed to the sun, and inside the flowers a lot of insect acftivity can take place in there while there is still snow outside because it generates heat. - - desiccation - drying out - - calm sunny days are the worst because if theres no wind and the plants absorbing solar energy that means that the inside of the plant is warmer thnamn the cold air outsiokde which would cause a heat gradient. - - confiders retain their leaves so size and shape is important - - they have a small leaf surface area - - they close their stomata in winter…all leaves have small pore openings called stomata which allow the exchange of gas and liquid, so they close this stomata to prevent them from drying up and losing more water from this. - - they have thick cuticles which prevents the loss of water through that. - - many peatland plants retain leaves all winter - - they also have hairs on the underside for some plants that reatrin their leaves - - if a plant is evergreen it retains its leaves all year round. - - some ferns retain their frawns through the winter (entire structure we see sticking up) - - evergreen ferns reduce the surface area by rolling up the leaves to reduce the surface area of the leaves. - - deciduous trees have big leaves with a large surface area - - akso known as hardwood trees and thgey do not have needles they have big broad leaves for manufactoring leaves for photosynthesis. - - their adaptation and response to subzero temps is to lose their leaves in the fall, but before they drop down to the ground the chlorophyll breaks down and they pull the sugars back down to the trunk and thus the colours hidden beneath part of the photosynthetic pathway shows. - - male red maples turn red …. red maples have separate sexes on each tree. females turn yellow - Flowers are bisexual - The colours are there already, true colours begin to appear - Called fall colours - - losinhg the leaves in a fall solves a second problem … snow accumulates… it can cause weight on the trees which can break off bracnhes… thus the leaves could be a bhigger area for snow to pile onto and thus the branches will break more. - Snow has weight that can break branches and leaves - - coniferous trees have a different shape and some are good for shedding snow… so short branches with small needles. - Small surface area - Shape is important, have shapes for shedding snow - Short branches, small needles, more weight it can have - The boreal forest dominated by spindly and spire-shaped trees (northern forest) - - balsam fir has a spire shape and black spruces are spindly - Black spruce are spindly, avoid holding snow - - if you get freezing rain building up it doesn't matter the shape, the freezing rain will build up and snap off branches - - excessive heat can cause desiccation, too mcuh heat can cause draught - Cause dessication, death, drying out - Plants reduce lead surface area by curline the leaves, close the stomata (pores for gas exchange) in extreme heats - - in extreme heat, plants reduce leaf surface area by curling the leaves. - Dont move around a lot, take a bath, water is attraction - - on hot days, many animals seek shady sights and be less actcive - - dragonflies reduce their surface area facing the sun, by a position called obelisk (german)…where the lift their body adbdomens so there is less of the suns surface hitting sun, aslo they get shade from tehir lower body being up. - Pointing its atom in the air, less surface area being hit by the sun - - dragonflies also shunt heat ti parts with a greater surface area… moving more of the liquid containing the ehat to the parts of the body which sees more sun like the abdomen. - - tiger beetles live in hot places on hot sand - - they elevate their body by stilting… where they elevate their bodies by extending their legs on that hot sand so they dont get the hottest part of the sand on their legs. - - in summer the rete mirabile is bypassed and more blood is shunted to the extremities … so they bypass the rete mirable and shunt more blood to the extreminities - - for beavers, they bypass the rete mirabile and put more blood into the tail which looses 90% more heat than when the rete mirabile is in operation. - - honeybees are social insects and they can work together to cool the hive… they use their wings to fan the hot air out of the hive. - They shove hot air out, wings are used as a fan to cool the colony - Vibrating to move hot air and create air flow out of the hive - Bees use evaporative cooling - Use mosisture, saliva - - foxes use panting.. which moves more air in and out which means theres more evaporation and when theres more evaporation which cools them. … evaporative cooling - Epose their tongue - Panting moves air out in and out very quickly - Evaporative cooling is panting - - birds can pant also - allowing more air to pass over the respiratory surfaces - - bees also use evaporative cooling by putting liquid drops on their body and when that liquid drop evaporates it makes it cooler - Mammals sweat also - - vultures employ a very unusal method of evaporative cooling… they excrete (pee) on their legs - Turkey vulture - They excrete on their legs, pee on their legs, a form of evaporative cooling - mourning doves employ the dangerous strategy of raising their internal temp to rise to 45 degrees celsius… becoming hyperthermia to cool off… - challenge n0.3… nutrition - Moruning doves employ the dangersou strategy - Widespread in north america, some living in the dessert - They allow the internat temp to rise as high as 45 degrres C - If temp goes up its dangerous for them - Hypothermia is below - Hyperthermia-mourning doves, higher, above normal temperature - Lower body temp, semi-hibernation sleep state called torpor Nutrition - plants can make their own food … but they need raw ingrediants - animals cannot make their own food… so they eat plants or eat other animals - Solutions, one to eat palnts or eat other animals - if youre an animal that eats plants, youre a herbivore - can eat leaves, fruit, seeds, nectar, sap, bark and twigs, some animals eat dead plant material too. - detritivore eats dead organic material - detritus = dead organic material - Eating plants- herbivore, herbivory - - detritivores can have food delivered to them - - water moves so if you wanna get organic material from the water you can filter from it… clams are filter feeders… they have a syphon that comes out, water comes in carryong organic material, they filkter it for organic material and then another syphon lets the filtered water come out, keeping the porganic material inside them. - - black fly- the baby (larval stage) are in water, so streams and they attach themselves to a rock to make a silk thing on the rock and they have hooks that hold them onto it and they hang onto it … they filter feed by their labral brushes from their mouth part come out and in the current they pull the water and filter the organic material and consume it. - - larger animals also filter feed - - they drain water through a filter and they get their organic material - - certain ducks do this (the dabblers or puddle ducks like mallards or swans)… they go upside down in the water with their bums in the air, bring up their bills and the water drains through the bill with a seive like mechanism called lamellae which are just water filters on the bills and the water drains through this and the organic material are kept inside. - - tongues also help filter the food from water… northern shoverler ( a puddle duck) this helps along with the lamallae on the bill. - - any kind of plant part that you use for food requires adaptations… for example nectar of flowers requires a long tongue called a proboscis on insects which goes down to suck up the nectar. a long proboscis is an adaptation for accessing nectar in flowers… they coil it up when they are not using it. - - hummingb irds dont have a long proboscis but they have a long beak and even longer tongue which goes down to get nectar. - - they extend their tongue through their hyoid horns which are at the base of the tongue, operated by muscles which pull the tongue in and out…. in some birds it wraps around the eye orbit … - - hyoid horns in hummingbirds and in woodpeckers (like yellow bellied sapsucker) for getting sap - - xylem brings water carrying sugars through the roots up to the leaves and branches, phloem does the opposit branches to roots… birds tap into xylem tissues in winter and tap into phloem tissues in summer. - - sap is a food and one way of getting the sap is to have an accessable toingue through the hyoid horns in sap suckers - - manby insects drink sap and they ahve a mouthpart they jab in into the stem to get the sap… this fine mouthpart is called the stylet which doesnt curl up. - - many true bugs suck plant juices - - aphids (true bugs) are sucking bugs… - - other animals eat plant tissues - - so leaves and stems etc. - - plant tissues are hard to digest because of tough structural components like cellulose - - the first stage is ingestion - getting the food into the digestive tract… - - slugs and snails have special mouthparts called a radula which is a structure they can stick out which rips off plant tissues and shreds the tissues. - - a radula allows slugs and snails to ingest their food. - - caterpillars have modified mandibles which are modified for cutting off plant tissues, analagous to the radula. - - some caterpillars eat leaves from the inside … lead bloth miner.., they are mining the leaf and extracting the material inside the leaf and creating a blotch. - - mammals use modified teeth for ingesting a plant material, which are called incisors … they are orange because a special ingredient in the enamel… in mammals.. especially rodents… the incisors have a lot of iron in the enamel to give it strenfgth which causes the orange colour… the back part of the tooth lack iron thus are white with more dentine… which gives the teeth a really sharp edge… the teeth of a beaver never stop growing and so they grow and wear them down at the same rate and the wearing makes them self sharpen - - moose have only lower incisors so they rip off plant tissues… they rip off the plant material more torn and messy instead of the sharp cuts of the beavers with large insicors. - - for mammals, large cheek teeth grind up the food… they ingest the food by using their incisors to snap it off and then they chew on it with cheek teeth which grind the food and are powered by large masseters and make it smaller to swallow. - - herbivores tend to have a large masseter and a small temporalis - - mandibles, radula, and cheek teeth all perform the same function but arise from different origins thus are analogous - - not many birds eat plant tissues, but some do … spruce grouse eat spruce needles… ruffed grouse have no teeth so after they bite off the plant tissue, they have a gizzard which grinds up plant tissues to smaller components… the gizzard is a big muscular structure with smaller inside with a lining with sharp little projections on it. in the gizzard, the muscle contracts and expands and grinds the material inside… the birds also swallow small birds and stones which help with grinding. - - after ingestiion comes digestion… slugs and snails produce digestive enzymes - - caterpillars dont produce the enzymes - - they can eat ten times their body weight everydaybut they waste a lot becasue they havent got an efficient way of digesting it so they just eat a lot to get a little absorption. - - big animals cant afford to waste a lot… - - for example moose, cows and deer get help from bacteria which are fiund inside tje rumen of thes tomahch in the rumen, the bacteria start digesting it. becasue plants are so hard to digest, after the bacteria start digesting, they cough it back up, chew it some more then send it back down - - simbiotic relationship… the mosse gets the food digested for it by the inhavbitatnts (bacterium), and the inhabitants get a safe warm place to live in and they get food. - - food is processed twice - ruminatinbg - chewing up the material is called rumination - - the snowshoe hare dont have a rumen, they have a special coil off the intenstine called a caecum full of bacteria which digests the food… hares and beavers have a ceacum. - - food comes down to the intestines but its not fully digested, but they cant throw it up again, they instead use their caecum and poop it out and eat it again called coprophagy… processing the food twice. - - birds that eat a lot of plant tissue also have a caecum, but they dont eat their droppings because thet have lots of food. - - porcupines dont eat their drtoppings, their digestive tract is very long about 26% of their total weight … full of bacteria so they dont have a rumen or caecum - - frugivores only eat fruit. - - fruit eating specialists - not 100% of diet byut a big part of it… bohemian waxwings … they have a very wide opening to their mouth called a gape… large gape for swallowing fruit whole… also cedar waxwing… large gapes allow for whole fruit swallowing which allow for fast external processing, also they have short intestines fior fast processing as well. and end result of around a 20 minute process of eating and pooping out seeds due to this fast processing from swallowing whole and short intestines. - - animals that eat fruit and pass out the seeds are called seed dispersers LECTURE 11: aggressive mimicry - mimicing sinething else in order to get a meal… they will do something bad to whatever comes in.. usually fopr a meal ant lion ○ insect ○ adults dont build traps ○ the larval stage builds the traps ○ trap made by ant lion looks like a pit or cone in the sane ○ the ant lion larvae lies buried in the bottom of the pit in the sand.. and when an ant or any other insect falls in, it bursts through the sand and grabs it, fgiving it a lethal bite to consume it. ○ it can injectr toxins with its mandibles ○ its trap is called a “pit fall trap” star nose moles ○ dig tunnels and patrols to wait for animal to attack ○ mole tunnels alligrator snapping turtle ○ tongue looks like a pink worm and under the water it wiggles it so when fish see it they come in and then the turtle will snap its mouth shut and eat the prey. ○ it uses aggressive mimicry part of its body is lure to attrack prey angler fish ○ huge mouth with teeth ○ they have an appendage on the head which glows and dangles it as a lure which attrracts fish and then it shuts its mouth and catches it. ○ aggressive mimicry argiope ○ special stabiilimentum and brightly coloured body as lure to draw in instects ○ aggressive mimicry photuris firefly ○ aggressive mimicry not getting it for meal but for chemicals it needs for pretection snowy egret ○ when they walk their feet come up and thier toes are bright yellow, and they hold them under water and wiggle them to attract fish to eat. ○ aggressive mimicry. once an animal either locates or traps its prey it then has to go to stage 2 to capture it and then you have to deal with it. owls locate prey with their face and capture prey with their feet… they have strong toes equipped with talons ○ most hawks and owls and eagles and falcons have these. ○ talons can be used to capture and to kill ○ owls have reversible toes because you have a better chance of grabbing animal when youre diving feet first in snow or darkness. osprey have special feet for catching fish ○ they have very muscular toes and huge talons ○ they hover in the air.. flying in air but staying in one spot then they plunge feet first in the water and they come up with a fish. when they are carrying it, they point the fish forward.. to capture and turn it around they have sharp projections called scales and they have outer toes which are reversible (owls also have reversible toes)… reverse toes are an adaptiation for capturing prey when its difficult to see them. great blue heron ○ they can grab a fish with its bill or if its larger can impale it with the mandible ○ sometimes the tongue can be an aid to help shove things down its throat. ○ swallow it whole loons also capture with their bills ○ tongue can aid as well merganser ○ long narrow bills ○ the inside of their beak has got tooth-like projections… called a serrated bill … thus they can hold on to slippery fish. birds that dive to catch their fish have their legs at the very back of their body.. this allows them to dive and swim underwater better. the diving ducks and loons cannot just jump in the air to take off, they have to run on the surface before they can take off because they are so front-heavy. ○ black ducks (puddle ducks) just jump into the air, doenst have to run… same with wood duck… because they arent so front heavy. mergansers have to run before flying becayse their legs are so far back that they are front heavy… same with cormomat. ducks running on surface will be a diver. ○ legs far back for better purpulsion under water. terns ○ hover in the air and dive head first into the water to get a fish. belted kingfisher ○ also hover and dive head first into water to catch tehir prey. river otter ○ use their teeth to catch fish ○ large teeth that are modified which are used for capturing their prey. raccoons - and all carnivores - have modified incisors called canines ○ tools of capture and often killing if youre using mouth to capture your prey with these canines, you need power from muscles called temporalis insect predatory animals - modfied mouthparts called mandibles ○ mandibles on tiger beetles are highly serrated and can shred their prey. frogs use thier tongues to capture prey. ○ they flick out their tongue and fold it up to flick it out toads and frogs use a tongue flick ○ eyes of frogs help them swallow woodpeckers also capture prey with their tongue ○ it must be extensible… they stick it out not flick it out… they have the hyoid horns which extends the tongue (these are muscles that are attached to the tongue tp extend the tongue) legs can also be used - in spiders that dont build traps they sue their legs - like crab spiders… use their legs with hairs… and praying mantids with their raptorial legs, fold their legs and snap them out and grab the prey with their raptorial legs. once a prey is captured they must dispatch it (kill it) ○ canines can be used in different ways foxes and coyotes use a “shake and break” method. — they grab a mouse or muscrat or something and shkae prey and break the neck. wolves kill alrger prey like deer or moose, they cant grab it to shake and breka so instead the slash it.. they repeatedly slash it with thier teeth and so it bleeds and go to shock… they use slash and shock. weasels bite into vthe back of the head into the brain case, so they bite into the cranium with their canines and their canines puncture the brain. cats kill with their canines, they bite into the neck and sepereate the neck vertebrae and break the neck with their teeth. ○ if they kill with their beak they use raptorial bills meathook tip… this is a modified tip which drops down and is pointed. shrikes also kill with their bill … they land on thier prey and wack it with their beak. ○ some hawks called bird hawks kill with their talons ○ not all animals kill their pray first, some swallow it whole. they have jaws that semi detach.. they can move their jaws sideways and the jaws can detach at the back making it open wide so some snakes can swallow it whole. ○ gray rat snakes and milk snakes are constrictors… they suffocate their pray. ○ rattlesnakes inject a toxin into their prey…. they are venomous (venom = injected toxins) also they inject digestive enzymes so the digestive process begins in the animal before they eat it. massasauga rattlesnakes. ○ crab spiders and assassin bugs inject toxins and enzymes into their prey to kill them then consume. ○ robber flies great eyesight, visual hunters have an injection mechanism for injecting the toxins and digestive enzymes into their prey… toxins to kill = venom and enxymes to digest. robber flies join crab spides and assassin bugs that are predatory animlas that inkect toxins into teheir pray. robber flies look like other animals like bumble bees… maybe a form of aggressive mimicry, maybe not. ○ short tailed shrew; only animal in north american that inject toxins intgo their pray to kill it. has a venomous bite. indigestible parts eg. crab spider captured a fly, munched up the fly to slurp the liquid after the enxymes have digested it but the shell is left. raptorial birds like a sharp shin hawk, can pluck the feathers off the pray and then can eat around the flesh, leabving the skeleton behind. ○ leave behind wings, skeleton and ate the rest ○ called selective feeding… selecting parts to eat leaving the indigestible parts. bears will skin larger prey pulliong the hide off to expose flesh porcupines are skinned by fishers … they skill the outter portion off to take off the quills. wolves tend to eat some of the hair on the animal as they devour the meat,, they feed selectively.. eat small bones … they pass indigestible passes through their body, so their droppings (scat) have small bone fragments and hair. ○ a lot can be told by the haris in the wolves scat. owls swallow small prey whole. ○ and about 12 horus later they cough out the indigestible parts which is called pellets… in the gizzard they sepereate the digestible and indigestable parts and couygh out the pellets. drawbacks to being a predator ○ prey fights back hooves and teeth etc. ○ accidents during the chase… eg. hawk dove into a thick shrub to get prey and got impailed on branch. break leg ○ ingestion of toxins bioaccumulation as larger animlas eat more smaller animlas with toxins they get accumalation of toxins in them. botulism starts off with little fish to bigger fish to birds that eat them peregrine falcons were driven to near extinction by DDT… DDT would build up inside the falcons from eating songbirds that would eat insects with DDT posion. resulted in thinner shells, behavioural changes and thus no youngs produced. ○ human prejudice bias against predator animals because they are competitors because they kill prey that hunters want.. also becasue they kill larger prey many think that they are dangerous. ○ #1 problem for predator is starvation make a kill 10% of time ○ predators are a major force in natural selection and evolution. prey developing new solutions and predators developing new ways to get them. LECTURE 12: short billed gull some animals eat another animal without killing it… eg. animals find a host and this host may be still alive. ○ parasites deal with libving animlas ○ parasites feeding on animal from outside = ectoparasites ○ parasites can be outside or inside animals ○ many leeches are ectoparasites in all stages get blood from sucking ○ ticks are also ectoparasites get blood moose ticks = ticks specifically for moose. as ticks feed on moose, they get itchy because moose get a lot of ticks and then the moose will rub it off and maybe take off its hair which can cause them to die from hypothermia in winter with hair loss. moose ticks get on moose in fall and are there all winter. ○ engorged female moose ticks big as a dime ○ as the host cools down gthat means no more food so the moose is dying or dead so they leave. ○ ticks can carry a disease which can effect other animals. ○ black legged deer ticks carry lyme disease. bacteria which causes lyme disease take 24-48 hours for bacteria to get to you, if you remove tik right away then its fine. key is backwash… when tik’s body gets engorged which means its full of blood then some blood spills back in you then. thats the problem. ○ some mites are ectoparasites often see them on insects arrenures mites are normally in the water and attach to the dragonfly nymph hitchike on, and when the adult comes out it will feed on the adult and then when it goes to the water again they come off. ○ many migratory birds harbour ectoparasites. they have mites that live inside the nostrils of birds. they have very special flys (ectoparasitic flys) that are flat with big hooks in their legs, and they crawl between the feathers and feed on their blood. ○ biting insects are not ectoparasites ectoparasites are animals that get all their nhutrition, all the time from a host. biting insects like deer flys and mosquitos only feed as females for egg development. ○ leeches, ticks etc. are ectoparasites! they are obligate parasites obligated to get their food that way ○ are clams ectoparasites? baby clams are ectoparasites on fish! they clamp onto fish gills. a baby clam is called a glochidium parasitic baby clam which gets onto fish gills female clam has mantle which is shaped like a minnow, it even wiggles it to look like an injured one… when a bigger fish ciomes down to look at the minnow for food, the clam senses the shadow of the fish and it shoots up the baby clams by the hundreds or more into the fish, and the clams clamp onto the gills when they go through it. these are from the ottawa river. have a modified lure to attract fish (not for food) to shoot out trheir parasitic larvae onto them. ticks find hosts by questing ○ in many types especiallky moose tickj and black tick… in late summer, the adults or sometimes juvenile ticks climb on vegetation and wait there with their legs and arms in air, and they have haller’s organ which detects humidity, temperature, and carbon dioxide, and thus they can use their organ to detect differnet features from the host, and when it identifies the host coming near, it goes down and climbs onto the host and begins to feed. ○ other adaptation = mouthparts to cut ○ barbs on hypostome ○ hypostome has little barbs which is almost like porcupine quills so when they shove in their mouthpart, they can open and close these barbs, and when their feeding the barbs are out so they are hard to pull out… ○ barbs are used to inject into the skin. mouthparts for holding and penetrating ○ leeches have cutting tools and suction pad ○ the suction comes from the mouthpart coming on and they use their cutting tools to open and get blood. ○ lamprey are a kind of eal.. an ectoparasitic fish… they also have a suction pad to clamp on and cutting tools for slicing into flesh of fish. anticoagulants to keep the blood flowing ○ ectoparasites want to keep the blood flowing so they add a special liwuid to it which contains anticoagulants to keep blood from thickening. flattened body shape is to climb through feathers, hair etc… (eg flat flies, lice). ○ and claws to grip ectoparsites have problems too ○ host dying- cant find host right away they will then die too. ○ hosts can try and remove them. ○ bird groom and preen their feathers (preening is a way of rwemoving ectoparasites with their bills) they can add compounds at the base of the tail which deter ectoparasites ○ herons have a grooming call or pectinate toe which is almost like a set of teeth on each of their toes, whcih is a tool for removing ectoparasites/ ○ beavers spend a lot of time grooming, they also have huge claws, and they have a special one, almost clam like double claws which are double or “split” toenails (or claws) and nobody knows for sure how these tools work, but its beleived that this special claw on two toes will rub them through their fur and take off ectoparasites… to groom using their split toenails. ectoparasites also live on inside of host = endoparasites ○ deer have a parasitic brainworm it is a special kind of internal parasite called a roundworm.. moose and deer are closely related animals and live in same neighboruhood, if a brainworm gets into a white tailed deer it wont hurt it, but if it gets into moose it will kill it. the larvae of the brainworm leave the deer in its droppings slugs or snails go to droppings and eat them… thus they now have the brainworm in them. and it cahnges their behvaiour so that the intermediate host eats in the daytime now… now this is the intermediate host which is temperary… it will not reproduce in intermediate host.. only in ultimate host like deer. deer eating leaf with parasite… leaves the digestive goe sto spinal area and moves up to sinuses and brain, as it matures, it can reproduce, eggs come down to digestive tract, out with the droppings, which are them consumed by snail or slug, until deer eats that slug or snail with the parasite. the deer is definitive or ultimate host because it reproduces in deer. many endoparasites have this 2 host feature. ○ for moose; it damages tissues as it goes, it eats part of brain not around the brain and thus the moose get the blind staggers where its disoriented, doesnt eat properly, etc. and dies. white tail deer and paraiste has evolved to live in harmony, but moose are not from north america, and when they began to live close to eahc other and then the moose has not evolved to live with them so they die. ○ robins are the definitive host for a parasitic fluke flat if robin poops out larval stage in water, it goes into an aquatic slug or snail, goes into intermediate host, and robins will eat it or young might also eat it, and the larvae will travel through the bird and live insied the robin. it can crawl up internally into the intenna like structures of the head on slug or snail, and make them grow larger, sometimes turn coilour, and look like a worm. and make the tenticle pulse and the robin can grab that and give it to its baby. ○ chipmunk or mouse bot fly; cuterebra is endoparasite only in the larval stage… only the larvae of this fly is an endopparasite on small mammals. the female robust bot fly lay their egg on the ground, when the mouse or chipmunk passes over the egg, the heat of the body makes the egg explode open, and grabs onto the hair above it and tries to find a hole to get into it like anus or mouth, it eats the flesh but it needs to breathe air so it cuts small hole… this does not kill its host and then it will turn into adult when it comes out. most endoparasites are tiny! ○ some parasites change behaviour in way where it doesnt want to mate… parasitic castration.. prevents host from going into mating phase for safety of parasite. ○ parasites have problems too interemediate host may nor be found wrong host might be entered host might die ○ parasites dont kill the host but predators kill their prey. parasitoids kill their hosts ○ generally these are other insects like caterpillars. ○ braconid wasps are parasitoids only in the larval stage. tiny wasps… the pupal cases mark the spot where the wasp larvae has eaten its way through the external skill of the caterpillar and has pupated on the outside.. the adult wasps are not parasitoids, they will lay their babies on the caterpillar. inside iuts body have a lot of tiny wasps eating its flesh while its still aluve and kill it. they then push through flesh and have cocoons on caterpillar to transform to adult. ○ tachinid flies are parasitoids as larvae super spiky ○ many flesh flies are parasitoids in the larval stage. ○ parasitoid flies lay its egg on caterpillar. ○ thread waisted wasp they find a caterpillar, paralyze it with a skin, drag it down into their tunnel, and lay eggs on it, and the larvae will eat the paralyze caterpillars flesh. ○ spider wasps do this too they are specialists for spiders the female spider wasp on the ground often shake its wings, tackle a spider, paralyze its spider, bring it down and bury it in its chamber to have its larvae on it. ○ both parasitoids in larval stage (but adult stage takes part by carrying and paralyzing); digger bees dig in the ground and paralyze the host… they drag pray and dig while carrying it, dig its self down with it and have larvae eat it… also great golden digger wasp (tend to go for larger insects). ○ cerceris (digger wasps) paralyzes jule beetles, they dig in really hard ground… biting the ground to soften it to use its legs to dig… it chews on the ground! cerceris digger wasp will spend night inside the burrow and seal it up from inside and when its morning she will open and she will guard it from other digger wasps. they have eyes and oselee on top which are sensory organs. some parasitoids find hosts through visual searching ○ when the right host is found, eggs are laid through the oviposator. ○ ichneumon wasps are a huge group of parasatoids ○ Megarhyssa ichneumon oviposators have supppeeer long oviposetors, they serve as a drill to go through bark of tree to host… they are trying to find grubs of pigeon horntails… pigeon horntails … they lay their eggs under bark and deposit fungus with the egg and the fungus grows and when the larvae grows it eats the fungus… maybne the ichneumon senses the fungus. they are specialiozed with long oviposators to drill through bark and get the eggs, and when the egg hatches the apralyzed horntial larvae is eaten alive. ○ some parasitoids are specialized pelecinid wasps lay eggs on june beetle grubs in the ground parasitoid fly will lay its egg on eggs of turtles as they are laid, when the egg hatches, the larval stage of the fly will burrow inside egg and will feed on the developing turtle inside. LECTURE 13: scavenging ○ animals that eat already dead animals (scavengers) foxes, and wolves scavenge but they also are predators and hunt! ○ especially in winter when food is hard to come by they will scavenge. martens, and birds might scavenge too. common ravens also scavenge but not full time. gulls will scavenge too but also not full time. ravens are scavengers primarily in winter.. usually feeding on leftovers from wolf packs… this is because winter is hard to find food. ○ if there were two bird silent scavenging, they are adults… juvenile ravens will scream and attract more juvenile ravne sto scavenge. ○ ravens may even follow wolf packs in winter waiting for them to kill. bald eagles my also scavenge. ○ eagles rae part time (facultative) scavengers in winter especially gulls scavenge extensivelly also but will eat live fish as well. ○ washed up fish or dead fish in water they might eat. ○ or live fish. turkey vultures are full time scavengers ○ they get all their nutrition from dead animals. ○ they are obligate scavengers ○ adaptations ; no feathers on the head … they stick their heads into really messy carcases so their heads will not get as much gross unhygenic things stuck to them. huge raptorial bill will meat hook tip on it carrion is detected primarily by smell… can find a carcas from more than kilometre away! they have enlarged nasal chamber… big area to analyze incoming scents. large olfactory bulb in brain… will analyze scents in the brain analyizng imput comibng in. vultures tend to fly very low, they dont do much flapping because that takes energy.. so they glide… they have very massive wings which are v shpaed… dihedral.. and they teeter back and fourth to help them fly low without expanding energy… they fly low and slow, soar and glide and teeter. vultures tend to communal roosting… getting infromation indirectly to find food… roosting in wide area, they can follow the vultures who leave first in the morning… information transfer. obligate scavengers = full time scavengers blow flies. green bottle fly ○ largely scavengers ○ obligate scavengers as larvae ○ they adult flies may lay eggs on the dead carcas so when the eggs hatch they will have a meal. carrion beetle ○ special intenna for piccking up the odours of a dead animal. ○ special sexual perfumes to attract a mate ○ they arrive at a dead carcus… ○ some carrion beetles are also called burying beetles once they are at a carcus, they will get under and move it to a softer spot to dig and bury it. golden necked carrion beetle… bury the carcus as a pair (sexual perfumes)… cut skin off underground tio make a pit in carcus and once babies hatch they will chew it up and feed it to them. some species of mites are

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