EVOLUTION PATTERNS
Horse Evolution
Evidence of Evolution Fossil record Homologous structures Vestigial structures Molecular biology Comparative embryology Artificial Selection Peppered Moths Antibiotic Resistance
Modern Example: Antibiotic Resistance
Trends/Patterns of Selection Original bell curve of population:
Directional Selection Example: elephant trunk length
Stabilizing Selection Example: human birth weight
Disruptive selection Example: rabbit fur color on black & white stones, black, white, grey
Frequency-dependent Selection Sexual Selection http://artscienceofnature.wordpress.com/category/phylum-mollusca/
DIVERGENT EVOLUTION Polar bear Brown bear
Species definition: two organisms that can mate and produce fertile offspring
CONVERGENT EVOLUTION shark dolphin tuna Counter shading fusiform shape
CONVERGENT EVOLUTION Australian marsupials vs. American placentals Coyote, groundhog, spiny anteater Tasmanian devel, wombat, banded anteater
Biogeography: Wallace’s Line
SPECIATION: allopatric sympatric
Bottleneck Effect
Founder Effect http://content.answers.com/main/content/wp/en/thumb/a/a9/150px-Polydactyly_01_Lfoot_AP.jpg
Speciation mechanisms Gradualism Puntuated Equilibrium
ADAPTIVE RADIATION Hawaiian honey creepers Darwin’s Finches
Artificial Selection
Hybrid Vigor (aka heterozygous advantage)
WARNING COLORATION aposematic coloring
MULLERIAN MIMICRY WASP
BATESIAN MIMICRY Monarch Viceroy Coral snake and California king snake Now thought to be Mullerian mimicry “Red touch yellow, kill a fellow. Red touch black, venom lack”
BATESIAN MIMICRY
CAMOUFLAGE
CAMOUFLAGE
DISRUPTIVE COLORATION
EYESPOTS/STARTLE
COEVOLUTION Rufous hummingbird & flower
Symbiotic: mutualistic Cleaner fish Clown fish and sea anemone Algae & fungi = lichen Bacteria in root nodules of legume
Symbiotic: mutualistic Ants & acacia trees Aphids & ants Oxpecker bird and ox
Symbiotic: parasitic tapeworm Strangler fig mistletoe
Symbiotic: commensalism Remoras and shark Barnacles on whale Sponge on scallop
EVOLUTION PATTERNS Revu Disruptive, Stabilizing, Directional Selection, Sexual, Frequency dependnt Divergent vs Convergent evolution Allopatric vs Sympatric speciation Gradualism vs Punctuated Equilibrium Adaptive Radiation Artificial Selection Mimicry and Camouflage Coevolution and Symbiosis