Animal Diversity Lecture Notes - BIOL 1604

Lecture 1 I.​ What makes an animal? A.​ Eukaryotic -organelles B.​ Heterotrophic (have to get their nutrients from eating other organisms) C.​ No cell wall II.​ Endosymbiosis A.​ Start with two independent bacteria, one bacterium engulfs t...

Lecture 1 I.​ What makes an animal? A.​ Eukaryotic -organelles B.​ Heterotrophic (have to get their nutrients from eating other organisms) C.​ No cell wall II.​ Endosymbiosis A.​ Start with two independent bacteria, one bacterium engulfs the other, one bacterium now lives inside the other, bot bacteria benefit from arrangement, the internal bacteria are passed on from generation to generation III.​ IV.​ Animal facts A.​ Smallest bird: bee hummingbird B.​ Largest bird: Ostrich C.​ Largest wingspan bird: wandering albatross D.​ Largest animal (and mammal): blue whale E.​ Smallest mammal by mass: Estruscan shrew F.​ Smallest mamma by length: Kitti’s hog-nosed bat or bumblebee bat G.​Longest-lived reptile: giant tortoise H.​ Fastest and largest invertebrate: Giant squid I.​ Longest flying migration: arctic Tern J.​ Most legs: Millipede  V.​ VI.​ Why is Diversity important? A.​ Intrinsic or aesthetic value B.​ “Insurance” C.​ Rivet Hypothesis 1.​ How many can we lose before ecosystem falls apart? D.​ Ecosystem Productivity and Services 1.​ Would cost 10s of trillion of dollars to replace VII.​ 1.25-1.5 million animals species have been described (named) VIII.​ There are 2 million and 9 million species of eukaryotes A.​ This does not include bacteria/archaea B.​ Scientists think we are still underestimated the amount of species IX.​ Example of biodiversity- Dr. Terry Erwin A.​ Fogged trees in tropical forests in panama​ B.​ Sampled 19 trees of one species (red oak) C.​ Found 1,200 beetle species (80% undescribed) D.​ Estimated that 163 species were specific to the host tree (red oak) E.​ There are roughly 50,000 tree species in tropics 1.​ Potentially million of beetle species in tropics alone?? X.​ Biodiversity hotspots A.​ XI.​ Mass extinctions A.​ Defined by the loss of at least 75% of species within a short period of time (geologically around 2 million years) B.​ C.​ Potentially living through a sixth mass-extinction event 1.​ 1 in 4 species are at risk of extinction 2.​ Habitat loss is a major threat to biodiversity 3.​ Rising CO2 levels, global warming  D.​ Lecture 2 I.​ Levels of complexity/specialization A.​ Nonliving (least complex to most complex)) 1.​ atoms-> simple molecules-> macromolecules ->membranes -> organelles B.​ Living (least to most complex) 1.​ cells-> tissues -> organs -> organ systems -> animal Lecture 3 I.​ *missed class, fill in with notes* Lecture 4 I.​ Iclicker question  A.​ As the surface area of a sphere increases, the volume of the sphere: increases at a faster rate II.​ Movement across cells A.​ Diffusion (simple or osmosis) Simple: mol. Move from high to low concentration Osmosis: diffusion of water, water moves from high to low water conc. a)​ Isotonic (normal) b)​ Hypertonic (shriveled/dehydrated) c)​ Hypotonic (swollen/waterlogged) B.​ Filtration Uses pressure to force solute molecules across a size selective membrane C.​ Active transport Moves solutes against the conc. Gradient using carrier proteins and ATP D.​ Endocytosis Bulk transport of material into cells a)​ Pinocytosis: cell drinking/non-specific uptake of fluid particles b)​ Phagocytosis: cel eating/ solid material E.​ Exocytosis Bulk removal of material out of cell III.​ Evolution of animal diversity (ch 1) A.​ Species: group of interbreeding individuals that have a common ancestry and are reproductively isolated from other such groups B.​ Population: group of organisms of the same species inhabiting a specific geographical locality C.​ Iclicker question Thomas R. Malthus was a British economist famous for influencing Darwin's theory of natural selection. What best summarizes the Malthusian principle? a)​ There are not enough resources to fully support the reproductive potential of a growing population. D.​ Charles Darwin Developed theory of natural selection a)​ Perpetual change Fossils provide evidence for perpetual change in forms, showing that organisms and their traits are constantly changing over geologic time b)​ Common descent Groups of organisms share common ancestors (a)​Vertebrae phylogeny was constructed using fossil record, comparing morphological and physiological traits, and DNA/RNA data (b)​Homology and ontogeny provide evidence for common descent (i)​ Homology: similarity in structure or pattern between organisms (ii)​ Ontogeny: developmental history of an org. (c)​ c)​ Gradualism Change happens gradually over long time periods (a)​Many small incremental changes-> long time periods -> large diff. In traits that characterize diff. Species d)​ Multiplication of species (speciation) E.​ Natural selection- mechanism of change 1.​ Genetics review Gene: DNA sequence that codes for protein Allele: alternate forms of a specific gene Mutation: random, source of new alleles Phenotypes (traits): visual expression of alleles 2.​ Evolution is the change in allele frequencies within a population, over time. a)​ Microevolution (a)​Change in allele frequencies within populations over time (b)​Mechanisms: (i)​ Mutation  (ii)​ Natural selection (iii)​ Genetic drift (iv)​ Migration 3.​ Genetic drift a)​ Change in allele frequencies in a population due to chance events, common in small populations b)​ Natural selection favors heritable traits that enhance survival and reproduction 4.​ Overview a)​ Variation within populations (genetic) b)​ Variation is passed on to offspring (heritable) c)​ Organisms produce more offspring than can survive d)​ Survival and reproduction are not random Lecture 5 I.​ Natural selection example A.​ Peppered moth 1.​ Natural selection favors light colored moths (better camouflage), then industrial revolution happens where smokestacks cover trees in soot, natural selection then favors dark colored moths 2.​ Adaptions a)​ Enhance survival b)​ Enhance reproduction c)​ IS NOT a conscious thought by an organisms to evolve an adaptation II.​ Sexual selection is a form of natural selection (mating rituals, different physical features, etc.) III.​ Three types of natural selection A.​ Stabilizing selection 1.​ Selects against extreme phenotypes (either ends of adaptation spectrum isn’t beneficial, stabilizes to happy medium between two extreme phenotypes)  a)​ B.​ Directional selection 1.​ Phenotypic character shifts in one direction (peppered moth example, shifts from one distinct phenotype to another) a)​ C.​ Disruptive selection 1.​ Selects against average phenotypes (opposite of stabilizing selection, favors one extreme or other, NOT average “happy medium” phenotype) a)​ IV.​ Iclicker question A.​ On a small island there is strong selective pressure for birds with intermediate sized beaks; birds with the smallest and largest beaks are selected against. What type of selection is this 1.​ Stabilizing V.​ Two situations in which genetic drift can have a significant impact A.​ Bottleneck effect  1.​ Types of disturbances a)​ Earthquakes b)​ Floods c)​ fires d)​ Overhunting e)​ Habitat conversion 2.​ Population size reduced 3.​ Some alleles lost or greatly reduced 4.​ Lower genetic diversity 5.​ B.​ Founder effect 1.​ Colonization of an island or patch by a small number of individuals 2.​ Very small “founder population” sizes 3.​ Occurs when a small group of individuals from a larger population becomes isolated and establishes a new population, leading to a reduced genetic diversity in the new population because the founding group did not carry the full genetic representation of the original population C.​ Genetic drift effects are more noticeable in small populations VI.​ Macroevolution A.​ Long term changes in allele frequencies B.​ Speciation 1.​ Formation of new species over geological time periods a)​ Reproductive isolation of populations (1)​Premating (prezygotic) isolation (2)​Postmating (postzygotic) isolation  (3)​ Lecture 6 I.​ Allopatric speciation A.​ Geographically isolated B.​ Exposed to different environments C.​ Accumulate differences via microevolution D.​ No longer able to mate successfully E.​ Most common form F.​ Vicariance event (event that isolates species) II.​ Reproductive barriers A.​ Example: congo river; 300 species of fish recently discovered, some within 1km stretch of each other B.​ Example: mobile cave in romania; atmosphere was 10% oxygen and no discernible food source, but 48 species live there, including 33 that exist nowhere else in the world III.​ Adaptive Radiation A.​ Production of many species from common ancestor within a short interval of geologic time (a few million years). 1.​ darwin’s finches are an example IV.​ Iclicker question A.​ Which of these is least likely to directly result in reproductive isolation via allopatry (i.e. a vicariance event)? 1.​ Climate change raises average global temperature 2 degrees celsius V.​ Summary A.​ Evolution is driven by 1.​ Mutations 2.​ Genetic drift 3.​ Natural selection B.​ This results in: 1.​ Speciation 2.​ Animal diversity Lecture 6 Chapter 2: Animal Ecology VI.​ Animal Ecology A.​ Relationship and interaction between organisms and environment 1.​ Abiotic and biotic 2.​ Incorporates a)​ Behaviors. b)​ physiology c)​ genetics d)​ Evolution 3.​ Helps us understand geographical distribution, abundance, traits/characteristics, and diversity of animal populations B.​ Hierarchy of ecological systems 1.​ Smallest to largest a)​ Organism b)​ Population (1)​Population ranges are limited to ecologically suitable habitats c)​ Community d)​ ecosystem e)​ Biosphere C.​ Fundamental Niche 1.​ Sets of conditions needed for an organism to survive and reproduce (mostly abiotic) a)​ Example -: 20-80 degrees F, 8-20% salinity , 6-8 pH, presence of food b)​ Using this, one can map out potential regions of occurrence  c)​ D.​ Realized niche 1.​ Actual range that a species inhabits after taking into account interaction with other species a)​ Limited by competitors, predators, pathogens, dispersal b)​ 2.​ Competition between species determines realized niche a)​ Example: Red legged salamander needs colder temps, so can only inhabit red highlighted area, but grey legged salamander has broader temp. Range, so can inhabit both red and grey areas. b)​ Red legged salamander aggressively excludes grey legged salamanders c)​  E.​ Iclicker question 1.​ Which factor could define an organism's fundamental niche and, therefore, would not be responsible for a relatively smaller geographic distribution described as the species' realized niche? a)​ A. minimum ambient temperature Lecture 7 I.​ Population demography A.​ Varies among species and different populations of same species B.​ Survivorship 1.​ C.​ Age structure 1.​ Shows if population is growing, stable, or declining 2.​ Carrying capacity limits population growth a)​ All pop. have intrinsic ability to grow exponentially, but limited resources and other extrinsic factors determine carrying capacity (K)  b)​ c)​ Examples: sheep population introduced to an island 3.​ Density dependent factors a)​ Influence on individual in a population varies with the degree of crowding (pop. size) (1)​ Food supply, temperature, places to live, precipitation, effects of predators, parasites, and diseases, catastrophic events 4.​ Density independent factors a)​ Influence on ind. In a pop. does not vary with the degree of crowding (pop size) b)​ II.​ Communities are associations of interacting populations A.​ Within populations: intraspecific interactions B.​ Within communities: interspecific interactions C.​ Interactions 1.​ Beneficial (+) 2.​ Detrimental (-) 3.​ Neutral (0) D.​ Competition occurs when there are limited resources (-,-) 1.​ Niche overlap a)​ Level of competition determined by level of niche overlap 2.​ Complete niche overlap → competitive exclusion a)​ One species outcompetes and excludes others 3.​ To coexist in same habitat, species must partition resources a)​ Diff. species specialize on different resources (less overlap) Lecture 8 I.​ Biological Interaction – Symbiotic relationships A.​ Mutualism 1.​ Both host and symbiont benefit 2.​ Example: clownfish and sea anemone B.​ Commensalism 1.​ Symbiont benefits but host is unaffected 2.​ Ex: cattle egret and cow C.​ Parasitism 1.​ The parasite received benefits at the host’s expense 2.​ Horsehair worm parasite life cycle a)​ Larvae born in water b)​ Larvae eaten by mayfly larvae c)​ Adult mayfly leaves water with parasite inside d)​ Mayfly eaten by cricket (parasite transfer) e)​ Parasite consumes crickets inner fat stores and grows D.​ Predatory/Prey 1.​ The predator receives benefits at the prey’s expense 2.​ Ex: rabbit and coyote a)​ II.​ Interspecific interactions shape many animal traits A.​ Camouflage 1.​ Cryptic coloration B.​ Mimicry 1.​ Batesian a)​ A harmless prey mimics a harmful prey b)​ Ex: yellowjacket wasp and yellowjacket moth 2.​ Mullerian a)​ Two different species that look alike and are both distasteful b)​ Both species benefit as predators are more likely to learn to avoid the coloration C.​ Aposematic coloration 1.​ advertises danger  2.​ Potential predators learn to avoid bright colors of prey (poisonous, spiky, foul taste) D.​ Keystone species strongly influence communities III.​ Ecosystem A.​ Definition: all population of organisms living in a certain area (community) plus their physical, abiotic environment (sun, water, soil, etc) B.​ Energy within ecosystems 1.​ Abiotic (sun) → autotrophs → heterotrophs 2.​ Autotroph (primary producer) a)​ An organism that assimilates energy from sunlight or inorganic compounds 3.​ Heterotroph a)​ An organism that uses organic (once living) materials as a source of energy and nutrients b)​ Herbivore (1)​ Consumes plants. c)​ Carnivore (1)​ Kills and eats animals d)​ Detritivore (1)​ Consumes dead organic material e)​ Omnivore (1)​ Consumes plants and other animals C.​ Food webs 1.​ Def: sequence of organisms through which energy is transferred in an ecosystem IV.​ Animal Architecture (Ch 3) A.​ Hierarchical organization of animal complexity (from least to most complex) 1.​ Protozoa a)​ Single cell 2.​ Cellular (sponges) a)​ Many cells/division of labor 3.​ Tissue (jellyfish) a)​ Layer of cells/ specialized function 4.​ Organ (flatworm) a)​ Aggregation of different tissues 5.​ Organ system (most animals) a)​ System of multiple organs B.​ Common architectural themes 1.​ Body symmetry a)​ Radial (1)​ Sessile or sedentary (2)​ Confront environment from all sides (3)​ Redundancy of parts (4)​ Less complex systems  b)​ Bilateral (1)​ Top and bottom halves (2)​ Bilateral symmetry line (3)​ Typically a cross section 2.​ Cellularity a)​ Protoplasmic (1)​ No tissues (2)​ Simplest eukaryotic organisms (3)​ Can form colonies (4)​ Many are parasitic (5)​ Example: amoeba b)​ Diploblastic (1)​ Two embryonic layers (a)​ Ectoderm- outer edge of cell (i)​ Develops intoEpidermis (b)​ Endoderm- inside cell, develops in gut (i)​ Gastrodermis (c)​ Mesoglea- jelly like substance between endo and ectoderm (2)​ Only radial animals (3)​ Example: Cnidaria and Ctenophora (4)​ c)​ Triploblastic (1)​ Body plans contain tissues derived from three embryonic tissues (2)​ Mesoderm- tissue layer between endo and ectoderm (a)​ Derivatives include: muscle and connective tissue (b)​ Supportive, contractile, blood cells, muscle cells (3)​ Inner tube: gut- mouth to anus- gastrodermis (4)​ Outer tube: body cavity- epidermis 3.​ Embryonic development a)​ Protostomes (1)​ Spiral cleavage (2)​ Blastopore becomes mouth  (3)​ Coelom forms by splitting b)​ Deuterostomes (1)​ Radial cleavage (2)​ Blastopore becomes anus (3)​ Coelom forms by outpocketing c)​ d)​ 4.​ Body activity a)​ Acoelomate (1)​ Mesoderm forms a solid mass of cells  (2)​ b)​ Pseudocoelomate (1)​ Body cavity not entirely lined by mesoderm (2)​ c)​ Coelomate (eucoelomate) (1)​ Body cavity completely surrounded by mesoderm (2)​ d)​ The coelom (body cavity) provides many advantages (1)​ Hydrostatic skeletons (2)​ Space and support for tissues/ organs (3)​ Increased body size (4)​ Protection for gut Lecture 9- Ch 4 Taxonomy I.​ II.​ Characters (traits) are used to determine animal relationships A.​ Characters must have a genetic basis B.​ Attributes or feature that indicate relatednness 1.​ Anatomical features 2.​ Behaviors 3.​ Sequence of DNA (recent) III.​ Cladograms A.​ Illustrate evolutionary relationships B.​ IV.​ Synapomorphies A.​ Derived characters shared exclusively by evolutionary descendants of a common ancestor  B.​ V.​ Homologous character arose from a single common ancestor A.​ All extant species sharing the common ancestor will have the trait B.​ homology= divergent evolution VI.​ Analogous character developed independently as adaptions to a common function A.​ homoplasy= convergent evolution B.​ C.​ Convergent evolution example: human eye and octopus eye, structured differently but have the same parts (eyelid, cornea, pupil, retina, etc.) VII.​ Monophyletic group: includes a single ancestral species and all of its descendants A.​ VIII.​