Unit 2 Ecology and Populations PDF

Topic 4: Ecology, Populations and Communities Levels of Organization: ○ Population: Same species in the same place at the same time ○ Community: All populations in one area ○ Ecosystem: All the organisms that make up a community PLUS the abiotic factors (ex. rocks)...

Topic 4: Ecology, Populations and Communities Levels of Organization: ○ Population: Same species in the same place at the same time ○ Community: All populations in one area ○ Ecosystem: All the organisms that make up a community PLUS the abiotic factors (ex. rocks) as well ○ Biosphere: Entire realm in which organisms exist (ex. The Planet Earth) Population: Same species in the same place at the same time ○ Ex. The number of Squirrels on NC State’s campus ○ Same Species: Group of interbreeding organisms that produce fertile offspring & don’t interbreed with other species Characteristics of Species: 1. Density: The Number of Individuals divided by the Unit Area 2. Dispersion: Pattern of spacing within geographic boundaries of a population ○ Types: Uniform: All are equal distance maximizing the most amount of space from each other Nesting Penguins that have evenly spaced nest distribution across the colony Random: Organisms are spaced out in an unpredictable pattern Dandelions’ seeds disperse in the wind and germinate whether they land that is suitable with no designated pattern Clumped: When individuals of a population are clumped together in groups due usually to unevenly distributed resources that the individual's group around. A herd of elephants that are grouped around a watering hole 3. Growth: The change in the number of individuals of a species in a certain area at a specific time. Depends on Biotic potential  ○ Biotic Potential: Maximum reproductive capacity of a species under ideal conditions ○ Population will exhibit Biotic Potential if: Everyone is surviving. Everyone is reproducing to the maximum they can, conditions are perfect, enough food for everyone (AKA perfect conditions) Seldom achieved in nature because species don’t rapidly expand in nature with no checks on their populations size Biotic potential results in Exponential Growth (J shaped curve) Exponential Growth: Reproducing at Maximum Rate Ex. Bacterium: In 20 minutes the number of bacteria would exceed the amount of electrons in the visible universe due to their super fast biotic potential Applications of Exponential Growth Model: Essentially looking at what would happen if a population grew uncheck and reached its Biotic Potential ○ Happens very rarely in nature due to limiting factors and is more so theoretical Used to Determine: ○ Bacterial Growth ○ Plant or insect growth of introduced species (such as invasive species) ○ Fish dynamics in fisheries ○ Conservation and Breeding Calculations: Population Growth (r): Rate of change in the number of individuals in the population per unit of time Change in inidviuals = ΔN Change in Time: ΔT Formula for Growth Rate: r = ΔN/ΔT r = (Births-Deaths)+(Immigrants-Emmigrants)/Total Population= Percent Change per year ○ Growth Rates and what they mean: r is positive (above 0): Population is growing r is negative (below 0): Population is declining r is zero: No, or Zero, population growth (ZPG) Doubling Time: The amount of time needed for a population to double in size  ○ When a population double, the amount of resources needed for that population must double as well 70/Percent in increase in population per year = How many it years it takes for the population to double Limiting Factors: Anything with the environment that can prevent the population from reproducing and therefore growthing more - Side Note: Humans arent affected the same way by density dependent limiting factors that organisms in natural populations are - i.e. cures for dieases, ability to build vertically, ship food so we don’t starve Types: ○ Density Dependent: Factors that limit population growth only when said population becomes too dense or “crowded” Ex. Predation: Will always be predation however the rate of predation increases as population density in the population increases Ex. Amount of Sunlight: The more crowded the trees are together due to the population being more dense, the less sunlight that filters through the leaves to the moss ○ Density Independent: Factors that limit population no matter what regardless of the density of the population is impacts and limits Ex. Flooding: Impact on population is not influenced by how dense a population is, it happens regardless Ex. Natural Disaster and Human Actions that cause limiting factors Carrying Capacity: The maximum number of individuals that the environment can support indefinitely Limiting factors, especially density dependent ones, determine the carrying capacity of an environment that a population lives in ○ Logistic Growth: Population will be fluctuating aroun “k” number of individuals Overshooting carrying capacity can lead to a collapse of a population due to extreme limiting factors such as starvation, parasites and dieases Types of Life Strategists: Based on species reproductive patterns and carrying capacity ○ “K” selected: Concerned with stabilizing and maintaining population at carrying capacity ○ Traits: Population is near or at carrying capacity Few offspring at a time, but reproduce multiple times through out life  Larger in size Typically put more energy into caring for offspring Have a stable environment that they live in ○ “R” Selected: Concerning with growing population that staying at carrying capacity ○ Traits: High growth rate Large amount of offspring at one time Reproduce once or very few times in their life Reach sexual maturatity at a much younger age Unpredictable environments so its benefitial to reproduce alot of offspring at one time Life Tables and Survivorship Curves Life Table: Shows data on the number of individuals alive at each particular age class (cohort) ○ Ex. How many individuals in a population are alive in the age cohort of 1-10 years old Survivorship: The probability of an individual to survive to a particular age ○ Relationship between two: Life Tables are used to plut Survivorship Curves Types of Survivorship Curves: ○ Type I: Most have a high likelihood of surviving until later in life. Mortality is low for a large span of years after birth and then likelihood or surviving decreases in older age Ex. Humans and most large mammals (Usually K strategists) ○ Type II: Mortality rate remains relatively constant throughout an organisms life spand. The chance of dying is equal at any age and so there is a 50%-50% chance an organism will die or survive at every age in its life span Ex. Rodents and some types of Birds ○ Type III: Most die early in life Usually “r” Strategists Seas Turtles, Frogs, Trees Demographics: Distribution of a population statitistics over time Growth is usually higher in developing countries (higher birth rates) and lower in industrilized countries (lower birth rates) ○ Agrarian Societies: Based around farming and producing crops Children are asset = High Birth Rate ○ Urbanized Society: Where society has moved away from being farm centered and instead of focused on building cities and where most people move to said cities Children are consumers = Low Birth Rate Demographic Transition: Movement from High Birth Rate and High Death Rate to Low Birth and Low Death Rates ○ Pre-Industrial: Both High Birth and Death Rate ○ Early Industrial: High Birth Rate, Death Rate begins decreasing ○ Mature Industrual: Birth Rate begins decreasing and Death Rate is Low ○ Post Industrial: Both Low Birth and Death Rate  Age Struture: Proportion of individuals in each age group ○ Rapid Growth: Large number of individuals in younger age groups compared to individuals in older age groups ○ Zero Growth: Equal number of individuals in younger age groups as individuals in older age groups ○ Negative Growth: Less number of individuals in younger age groups compared to individuals in older age groups Ecological Footprint: How many resources are used by each individual ○ Aka the more resources you use the larger your ecological footprint will be  Species Interactions: Ways that species interact with one another ○ Major Types: 1. Competition 2. Predation 3. Parasitism 4. Symbiosis 1. Competiton: Interaction between two species or organisms in which both strive for the same limited resource Can be between two different species or the same species ○ Intraspecies Competition: Between the same species ○ Interspecies Competition: Between two different species Competition is negative for both species or organisms involved in it ○ It lowers the fitness of both organisms involved due to the presence of one organism always reduces the amount of resources available for the other Ecological Niche: An organisms role in an ecosystem, its tolerance limits for abiotic factors, and requirements for shelter ○ “What it does in an Ecosystem” ○ Habitat is the Address, Niche is the species Job Ex. An oak trees niche is that it provides shade, produces acorns, and shelter for squirrels Competition Exclusion Principle: Two species cannot coexist in the same ecological niche if they compete for the same limited resource. One will outcompete the other, leading to extinction of the organism or species it out competed ○ Discrovered by Georgii Gause in 1934 ○ Applies to species occupying the same or very similar niche due to them needing the same or similar resources in said niche “Complete Competition Cannot Coexist) Types of Niches: ○ Fundamental Niche: Full spectrum of resources potentially available to an organism What would organisms would able to occupy without the worry of competition  Ex. For a fruit eating bird, its fundamental niche would be access to all the fruit producing plants in it environment Ex. Barnacles on a rocky shore being able to occupy a wide range of rock surfaces and locations due to the absence of competition from other species in the same or similar niche ○ Realized Niche: The Resources that are actually and realitsically available to an organism Organisms stick to their realized niche to avoid competition Ex. Barnacles on a rocky shore are only able to occupy the higher, dried areas of the rock due to competition while another type of barnacle would occupy the lower, wetter areas of the rock Resource Partitioning: When different species in the same ecosystem or ecological niche use many of the same resources so in order for both to be able to survive and avoid direct competition they divide up the limited resource so that they are able to both use and coexist at the same time ○ Ex. Different species of birds in a forest have evolved to forage at different levels of the tree canopy so that they can all coexist by utilizing different parts of the available resource Character Displacement: When natural selection favors traits that reduce competition between species that live in the same ecosystem or niche, resulting in them diverging to have both different characteristics and resource use in order to avoid competition ○ Ex. Identical twins become different in terms of personalities, characteristics, clothes styles, etc, because they want to separate themselves  Live in the Same Environment: Different characteristics are likely to emerge (aka character displacement) especially in sympatric environments Live in Different Environments: More likely to be similar (aka not see character displacement) especially in allopatric environments 2. Predation: Consumption of prey species by predator species Beneficial only for predators in this relationship (since prey die) ○ Catching Prey: Predators may either conceal self to avoid notice or outright attack prey Co-Evolution: The process of two or more species evolving together in response to each others selective pressures ○ Defense Mechanisms of Prey: Adaptations prey have developed through natural selection and evolution in order to survive and escape predations Camouflage: Adaptation of an animal that involves the use of coloration, patterns, or shape to blend in with its environment to make it difficult for predators to detect them Types of Camoflauge: ○ Cryptic Camouflage: Involves blending into environment to hide from predators ○ Transparency: Light reflects and makes an animal almost seem invisible in order to hide from predators Mimicry: Adaptation where an animal develeops physical characteristic that closely resemble another organism (that theyre not closely relate to) in order to survive by tricking a predator Mullerian: Where two or more species that are dangerous, especially in terms of toxicity, that share commone or similar predators have adapted to look very similar to one another ○ Share an apposematic coloring ○ Ex. Hornets, bees, and wasps all look similar to each other and are able to sting in order to defend themselves from predators Batesian: Harmless species that have adapted to resemble other species that are deadly in order to trick predators into not engaging ○ Ex. The King Snake (not poisonous) will mimic Coral Snakes (poisinous) in terms of color in order to trick predators into staying away from them Advertise Unpleasant Attribute:  Apposematic: Where a toxic or dangerous prey shows off its toxic nature through its coloring in order to repel and ward off predators ○ Basically a coloring that acts as a warning signal to predators to not engage ○ Ex. Poisin dart frogs have vibrant colors that warn predators of their poisonous nature Divert Attention: Make predators divert their attention by using a distraction display whic could include making sounds to warn the rest of the pack plys confuse a predator, sudden movements and other visual displays Playing Dead: Predators usually do not like eating aleady dead prey due to the risk of disease or other bads things associated witha dead animal Ex. Possums, Hognose Snake Mobbing Behaviour: Group of prey, such as a herd, actively approach and harass a predator by making loud noise and aggressive movements to scare predator away and lower risk fo predation Ex. herd of water buffalo charging at lionessess to scare them away Decorate self using surrounding environment: Form of camouflage where prey decorate themselves with pieces of their environment to blend in better and hide form predators Ex. Decorator crabs attach seaweed, shells, etc to their exoseletons to match their environment Disruptive Coloring: Form of camoflage where an animal has high contrast pattern, such as stripes, to break up the animals outline and make it more difficult for it individually to be detected. Works very well in a herd setting because it is then much harder to pick out and attack individuals wth this coloring Ex. The black and white stripes of a zebra make it harder for a lion to identify a single individual in the herd to attack Fighting Back: Prey actually fighting back against predators Ex. Porcupines shooting their quills at a potential predators or threat Predators Effect on Population Cycles: Predators can act as a regulator in many food chains and ecosystems, especially in terms of controlling prey populations  ○ Ex. Population Cycle: Predators Increase = Prey Decrease Prey decreases = Predators Decrease Predators Decrease = Prey Increase ○ Also help maintain ecosystem health Ex. In the amazon rainforest, the agouti eat palm seeds, bury them to come back to later to eat. The agouti gets eaten by ocelot, which means they never come back for the seeds they buried. This allows for palm tree populations to grow by allowing those buried seeds to grow into actual trees all due to the ocelots predation 3. Parasitism: One species benefits from harming another species while that other one is just harmed with no gain from the interaction Pathogen: A parasite that causes disease or even death to a host (50% of all species are parasites) ○ Endoparasite: Parasite that lives inside the host Ex. Tape worm, heart worm ○ Exoparasite: Parasite that lives on the outside of a host, like on the skin or in hair Ex. Tick, Flea Social Parasite: Relationship where one species exploits and uses the social structure and behavior of another species ○ Basically relying on a host species to exert its energy into raising and caring for the parasites species young ○ Usually works with closely relates species (if the parasite and host species are similar) Ex. Cuckoo birds laying their eggs in other species of birds nests for them to raise instead of their own chicks 4. Symbiosis: A close, long term interaction between two different species Mutualism: Both species benefit from the interaction ○ Ex. Pollinators and flowers Commensalism: Interaction between two species where one species benefits and the other isn’t really affected ○ Ex. bird nesting in a tree  Communities: All the different species in the same area that interact with each other Almost all communities are disturbed at some point ○ Disturbance: Event that changes a community, removes organisms, or alters it in some way Ex. Natural Activity: Storm, Flood Ex. Human Activity: Logging Intermediate Disturbance: Moderate disturbance that can create opportunities for the community ○ Ecological Success: Community Developed over time, gradual change in plant and animal life in an area Pioneer Community: The initial group of colonizing species in a previously bare or disturbed area (usually r species) Create an environment that is suitable for later species Ex. ​A group of lichens and mosses growing on bare rocks after a disturbance like a volcanic eruption Climax Community: The final, mostly stable and developed stage representing a stable environment with a diverse community Comes much later, after the pioneer community Biome: A climax community that is extensive and well defined Ex. A well defined and stable Deciduous Forest ○ Types of Ecological Succession: Primary Succession: The very beginning step of ecological succession where pioneer species colonize a newly formed lifeless area Happens when a new patch of land is created or exposed for the first time Usually starts with soil formation (literally starting from scratch) Secondary Succession: Ecological process where pioneer species re-establishing themselves in an area after a disturbance that significantly reduced the population but did not remove the soil, allowing for faster recolonization compared to primary Do not have to start from scratch since soil is already formed Ex. A forest ecosystem regrowing after a fire  ○ Aquatic Succession Eutrophication: Process where nutrients gather in a body of water leading to increases plant and algal growth, resulting a boom in growth of decomposing microorganisms that lead to the depletion of oxygen in the water, causing populations of other species in the body of water to decrease Is a natural process, but is heavily increased and sped up by human activities, specifically runoff from farms into lakes and pond Ecosystems and Nutrition Requirements: Ecosystems: All organisms that make up a community AND their physical environment (includes abiotic factors) Interact Through: 1. Flow of Energy 2. Cycling of Materials Energy: You can’t recycle it, it flows one way through an ecosystem ○ Energy used in ecosystems = Comes straight from the sun Materials: Water, nutrients, etc CAN be recycled in an ecosystem Four major factors concerning environments and food webs: ○ The Abiotic Environment ○ Primary Producers Autotrophs: They make their own “food” by converting energy from sunlight into chemical energy Includes Photographs and Chemographs ○ Consumers Heterotrophs: Cannot produce its own food and therefore gets its nutrients by consuming other organisms, such as plants or animals Types: ○ Primary: Herbivores (eat only primary producers) ○ Secondary: Eat primary produces ○ Omnivores: Are both Secondary and Primary consumers ○ Decomposers and Detrivores Detrivores: Animals that feed Detritus (Dead plants and animals plus their waste products)  Ex. Earth worms, Crabs Decomposers: Usually microorganisms break down dead organic matter by secrete digestive enzymes over the dead matter to break it down into simpler and more soluble substances Saprobes: Type of decomposer, typically fungi, that absorb nutrients from dead organisms Ex. Fungi, Bacteria Nutritional Requirements of Each Type of Organism Prokaryotes: Simple, single celled organisms that does not have a distinct nucleus or membrane bound organelles ○ Some prokaryotes have specific nutritional requirements, while others can consumer about any organic molecule for nutrients ○ Adaptations of Prokaryotes: Obligate Aerobes: require oxygen to survive Facultative Aerobes: Can use oxygen if its there, but does not absolutely require it in order to survive Obligate Aerobe: Can’t use oxygen, it will die it is in the presence of oxygen Aerotolerant Aerobe: Can tolerate oxygen, it wont die like obligate Aerobes will, but it still can’t use oxygen in respiration Eukaryotes: Organism, can be multi or single celled, that is more complex due to it having a distinct nucleus and membrane bound organelles Protist: A Eukaryote that is not a animal, fungi, or plant. Can be both single and multicellular Ex. Amoeba, Red Algae ○ Heterotrophic Protists: Protists that ingest other organisms for nutrience Phagotroph: Organisms that obtain nutrients by engulfing and digesting other organisms or organic particles Ex. Amoebe uses its pseudophodia (fake limbs) to accomplish this Osmotroph: Obtains nutrients by absorbing dissolved organic matter from surrounding environment via osmosis Ex. some types of bacteria and fungi gain nutrients this way ○ Fungi are considered osmotrophs because they subtrate feed which is a type of osmotrophy  ○ Autotroph: Create own nutrients by converting sunlight energy to chemical Ex. Plants and flowers that use photosynthesis for energy ○ Mixotrophs: Can create its own nutrients through photosynthesis but can also consumer other organisms for nutrients Switch between being heterotrophic and autotrophic depending on the environment Ex. Euglena consume other organisms but it can also utilize light energy to synthesize their own food ○ Saprobes: Fungus like protist that feed on dead organic matter, acting as a decomposer Mold, yeasts ○ Parasites: Protists that must gain its energy from a host organism, such as a human or animal Ex. Malaria parasite and Giardia Fungi: Any group of spore producing eukaryotic organisms that feed on organic matter (not autotrophic) They can be considered both pathogenic and parasitic due to how they gain nutrients and also the harm they can cause to other organisms especially with their spores Can secrete enzymes and store nutrients like animals Haustorium: Root like structure that grows from a fungus that grows into or around structure that allows it to absorb water and nutrients through osmosis ○ Substrate Feeders: Organism that lives and grows in the thing that they eat and absord the nutrients in where they are growing and living (aka are osmotrophs) Substrate: Soil, rotting log, piece of bread, living tissue Ex. Fungi, most worms, caterpillars that eat the leaves they live in ○ Extracellular Digestion: Digest food before absorbing it by secreting enzymes on it Ex. Fungi secret enzymes onto its food, allowing it to breakdown before the nutrients is then absorbed through osmosis Animal: Any multicellular, Eukaryotic organisms that belong to the Kingdom Animalia ○ Suspensions Feeders: Animal that filters or sifts through food particles from water  Ex. A sponge filters small food particles from the water by pumping water into their own bodies in order to draw in food particles ○ Fluid Feeders: Suck nutrient fluids in from other organisms as a source of food Usually includes parasites and pollinators Ex. Vampire Bats (drink blood), Humming Bird (drinks pollen from flowers) ○ Bulk Feeders: Eat Large pieces of food using adaptations such as claws, teeth, pinchers, fangs etc. Humans are bulk eaters Lions chewing on the meat from a freshly killed prey Plants: A multicellular eukaryotic organisms that is, usually, able to photosynthesize, has cell walls around each cell, and is usually stationary ○ Require Certain Nutrients: Nitrogen, Potassium, Calcium, Phosphorous, Magnesium, Sulfur, etc. Usually obtain these from the soil or animal droppings Nitrogen Deficiency: When plants get enough nitrogen from the soil and need fertilizer, they're leave can turn yellow Cyanobacteria: Supply Nitrogen to plants due to its role in the carbon cycle by changing atmospheric N2 into Ammonium that can then be used by the plants for nutrients ○ Require Water (H2O) and Carbon Dioxide (CO2) Mycorrhizae: Type of Fungus that grows on plants and actually helps the plants absorb nutrients Parasitic Flowers: Tap into vascular tissues or another plant and no leaves or roots of their own ○ Vascular System of Plants: Specialized network of tissues that transport water, nutrients, and sugar around the plant, from the leaves to the roots Xylem: Transports water and dissolved minerals upwards from the roots towards the leaves (one way only) Transpiration: Evaporation of water from leaves of plants by H2O leaving the pores of leave that are meant for gas exchange with O2 and CO2 ○ Helps to pull water up the xylem of a plant due to water molecules forming a kind of chain and so every time that a H2O molecule leaves through a leaf pore, the other H2O molecules are pulled up one Stomata: The leaf pores on the underside of leaves that plants use for  gas exchange plus the evaporation of water from the plant ○ Stomata have guard cells on either side of the opening to let gas in and out ○ On the underside of the plant due to the fact that transpiration is increase by the amount of sun light, and so therefore being on the underside of leaves would prevent too much water loss from transpiration due to less sunlight Transpiration is able to help with the transportation of water up the xylem due to waters properties: Cohesion: Water molecules like to stay together due to the H partial positive charge and the oxygen partial negative charge that both attract other water molecules through hydrogen bonds Adhesion: Due to water molecules polarity, with its partial positive Hydrogen and partial negative Oxygen, H2O molecules are also attracted the the cellulose walls of the Xylem ○ Cohesive-Transportation Theory: Basically how water is transported The sun directly powers Transpiration Cohesive: Water molecules “stick together” due to hydrogen bonding Tension: What is exerted on water by evaporation on leafs surface due to it pulling up a continuos stream of water molecules in the plant up the xylem to the leaves from the roots Phloem: Tissue that transports sugars from the leaves or other storage tissues to the other parts of the plant that need them “Source to Sink”: Where there is an excess of sugar to where there is a lack of sugar (usually from leaves to roots or other parts of the plant such as the stem, buds, flowers ○ Always moves down sucrose gradient Translocation: How sugar is transported in the Phloem  ○ Sugar loads into the phloem from the leaves, causing water to diffuse into the phloem, causing pressure to build, meaning that sugar and water flow to where there is less pressure in the plant aka where there is not a build up sugar Pressure-Flow Model: From areas of high pressure to low Flow of Energy Trophic Levels: Hierarchical levels in the ecosystem comprised of organisms that have similar sources of nutrients and energy ○ Represents an organisms “distance” from the sun in terms of the initial light energy given off from the sun Energy from the sun is transferred through food chains via producers turning light energy into chemical energy and then being consumed by primary consumers and so forth Keystone Species: Species whose impact on its community or exosystem is much larger and influential than would be expected since theres not a lot of them in terms of population in an ecosystem ○ Large Impact; Small Numbers = Keystone Species Ex. Beavers, Elepants, Sea Otters Starfish Flow of Energy in a Ecosystems: Is linear, meaning it cannot be reused ○ Each time energy is transferred in an ecosystem, meaning it goes from one trophic level to another, about 90% if that energy is loss between each trophic level aka only 10% is transferred one trophic level up The food chain is limited by this inefficiency in energy transfer Bioaccumulation: Accumulation of toxic chemicals in organism that is passed upward in the food chain ○ Toxicity accumulates in organisms due to toxic chemicals not being able to be broken down in the organisms body so it collects and accumulates in the fatty tissue, what is what organisms in the next trophic primarily eat so the toxic chemicals are then passed on to them Higher Trophic Levels have higher levels of bioaccumulation due to them eating the large quantities of lower trophic level prey so they therefore have a higher concentration of toxic chemicals due to these toxins not degrading in the preys bodies  Plant Productivity: The amount of organic matter, aka biomass,produced in a given period of time determined by how much ATP that produce from taking in sunlight and converting it into carbohydrates first ○ Types of Primary Production: Gross Primary Production: Amount of light energy that is converted to chemical energy by photosynthesis per unit of time How much energy is initially produced by a plant before anything like respiration ○ Basically Photosynthesis (how much light energy is converted to chemical energy) Net Primary Production: The amount of energy that is left other in plants after the process of respiration which takes away from the initial energy formed (the GPP) Equation: Net = Gross - R (energy required for Respiration) ○ What you have left after this is Biomass, or specifically the energy accumulate in Biomass NPP = Biomass ○ Biomass: Weight of vegetation added to the ecosystem per unit of area per unit of time (g/m^2/yr) ○ About Productivity: Usually areas are the most productive around the equator due to increased sunlight and rainfall Most productive areas: In terms of all of Earth Surface Area: The Open Ocean ○ Has largest amount of area Average Net Primary Production (How much Biomass in g/m^2/yr): Algal Beds and Coral Reefs, Tropical Rainforest, Swamp and Marsh ○ Limits of Productivity: Aquatic: Light (depth of light penetration) and amount of nutrients in water Terrestrial: Temperature and Moisture Human Impact on Biosphere (aka Earth): Industrialization: Produced a lot of waste and carbon into the atmosphere ○ If our population was much smaller = Much less impact  Human Activities: Contribute to the declining biological diversity on the planet As human population increase, so does the number of extinct species Humans have wiped out about 60% of species from 1970 to now. This includes reptiles, birds, fish, invertebrates, mammals ○ Pollution: As population increases, so does the our amount of pollution Garbage: The U.S. alone throws away 270 million tons each year with 66% of it ending up in the ocean How giant garbage patches are formed in the oceans ○ Waste: Humans are very wasteful creates Majority of all environmental problems are connected to waste About ⅓ of all food rots Plastics in the oceans and on land Nitrous and phosphorous from fertilized fields in water (causes Eutrophication) How Human Activities reduce Biodiversity: ○ Habitat Fragmentation: Parts of a habitat are divided and separated from one another Makes it much harder for animals to fid resources especially if they are adapted to need a very large area of territory Ex. Due to habitat Fragmentation, muriquis monkeys are starting to live on the ground instead of the trees due to a large density increase of monkeys in trees due to habitat fragmentation and so the monkeys have no where else to go ○ Deforestation: Can lead to soil erosion, lake and river water levels decline, and desertification can occur due to the soil left being without nutrients Facts:  50-70% of the earth has been modified by humans 7 football fields were lost every hour in brazil When modifying land, humans are likely to make contact with animals and therefore increase the chances of pathogens from the wild being spread to humans Causes of Deforestation: Subsistence Agriculture: Growing food for ones own family and not specifically for profit Logging Cattle Ranches Wood for Fuel Commercial Farming (opposite of Subsistence Agriculture) ○ Humans bringing foreign species to non-native habitats: Invasive Species: Foreign species that disrupt a natural ecosystem or harms humans health and economy Basically a foreign species that does harm by disrupting ecosystems and reducing biodiversity Introduced Species: A foreign species from elsewhere that could have a positive OR negative impact on the ecosystem Examples of Invasive Species: ○ Starling and Pigeons (Brought from Europe due to being mentioned in Shakespeare works??) ○ House Finches (From western U.S.) ○ Giant African Snail (Brought to U.S by little boy who released it in Miami) ○ Kudzu (initially brought from japan as a way to stop soil erosion, then became incredibly invasive) ○ Asian Carp in Great lakes (Huge fish in the great lakes tha jumps whenever it gets scared by boats)  ○ Nile Perch (introduced into lake victoria, is now a predator of the Cichilik) Endocrine Disruptors: Synthetic compound that interferes with endocrine system of animals Toxins that can act as endocrine disruptors: ○ DDT- Pesticide ○ PCBs - Coolants and in Industry ○ Pesticides ○ BPA- Plastics ○ Dioxins- Industry, waster and incineration ○ Heavy Metals- Lead ○ Asbestos- Fire Proofing Global Warming/Climate Change: Long term increase in the Earths average temp Caused by an over accumulation of Green Houses in the Atmosphere due to human activities ○ These gasses include CO2, Methane, Nitrous Oxide CO2 is released through fossil fuels (which contain carbon since they were once alive organisms) Release of Carbon and other gasses through burning of fossil fuels acts as sort of blanket in the atmosphere so that instead of light energy from the sun being reflected back out into space, it is trapped in this blanket of gasses causing the overall temperature of the earth to go up over time ○ Relationship between the release of Methane and CO2: Methane is primarily found as a natural gas in the North and South poles under layers of ice, so when CO2 in the atmosphere increase and therefore  more heat from the sun if trapped, ice in the north and south pole melt and release methane Affect Climate Change has on Organisms: ○ Animals: the Pika are decreasing due to needing a cold habitat and their environment continues to increase in temp every year, forcing them to migrate farther and farther form their original habitat ○ Plants and Trees: While a large amount of CO2 does help trees grow, a reverse side effect is that trees are bigger but their wood density is decreasing making them weaker Models cannot prove that humans are involved, HOWEVER the changes observed are consistent with human causes ○ Models do not account for some complexities of climate such as the feedback effects of water vapor and cloud formation etc. ○ Scientists say that the models are so sufficient, about 95% accuracy, that the amount of climate change observed in the last 50 years is not from natural causes alone