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40 Cards in this Set

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Directional Selection
Reduces genetic diversity by favoring one extreme.
Stablizing Selection
Selection for mean, against extreme phenotypes. Reduces Genetic Diversity.. Really big/small infants have high infant mortality
Disruptive Selection
Against mean
Sexual Selection
Subject of natural selection. Caused by differences between sexes in likelihood of getting sex. One sex can drive evolution.
Bateman's principle
Female reproductive success limited by resources. Male RS limited by access to mates.
Runaway Selection
Females choose more and more ostentatious mates. (elk with antlers)
Theory of Natural Selection
Variation in population
Heritable in population
Some variants at selective advantage
Successful variants survive, pass on genes
Sesamoid bone
Grizzly bears like to kill things, using their big claws. Doing so puts a stress on the wrist. Radial sesamoid bones appeared, extra bone in wrist, which strengthened wrist. Sesamoid bone moved to become extra digit for panda, because panda bears don’t really need to kill their bamboo sticks…
Structure that has a secondary function not related to original function
Sexual Reproduction vs Asexual reproduction
Asexual reproduction: offspring have 100% of mom's genes.
Sexual reproduction: 50% genes lost every offspring
Muller's Ratchet
Sexual reproduction reduces expression of deleterious recessive alleles: AAxaa=Aa
Lottery/Tangled Bank Hypothesis
Better to produce variable offspring than clones because environment always changing.
Red Queen Hypothesis
Sexual reproduction lets organisms respond to changing environment. Lions adapt, then gazelles adapt, then lions.
Morphological species concept
Individuals that look alike belong to same. Only useful for species paleontology.
Biological Species Concept
Species: group of individuals capable of interbreeding
evolution within a species
evolution creates new species
Sympatric speciation:
Macroevolution that occurs in a single area. New plant flies over, half of soapberry bugs stick with eating old ones, half eat new ones. Rare.
Might support sympatric speciation. Mutation wouldn't species to mate with other species.
Allopatric Speciation
Requires geographic isolation. Two types:
Vicariance: Environment changes/isolates
Dispersal: big group splits, no interbreeding, adapt on own.
Lobe-finned fishes and tetrapod link.
Lobe-finned fish vs. ray-finned fish
Lobe finned fish became tetrapods
Ray-finned fish became fish
Made Systema Naturae. Unwittingly created clades
Monophyletic vs. paraphyletic vs polyphyletic groups
M:Includes common ancestors and all descendant species.
Para: Includes CA and some DS
Poly: Includes some CA and DS
Homologous vs analagous structures:
Structures with same evolutionary origin
Structures with same use, but different origins
Willi Hegnig
German, published book called Phylogenetics. Created technique called cladistics.
Methodology of Cladistics
Choose an outgroup just outside of clade you're looking at. Score as many characteristics as you can.
Angelmann's vs prader williams
Both same DNA missing.
Angelman: very retarded, skinny. MOM
Prader: very Fat. DAD
Simplest pathway for cladistics
Shared derived traits vs. shared ancestral traits
Shared ancestral traits aren't useful. Shared derived traits Are.
4.6 bya-600 mya
600mya-230 mya
250-60 mya
60 mya less
Types of Fossils:
No decomposition
Sediments accumulated on top/compressed into carbon rich film
Branch decomposes, hole left is filled with minerals, becomes cast
petrified wood, etc
First bird fossil
Phyletic gradualism
evolution occurs slow but sure
Niles Eldridge and Stephen J Gould
Argued for punctuated equilibrium
Punctuated Equlibrium
Short bursts of change then long periods of no change
Quantum speciation
Some big event changes everything, like river deviation/lava flow
most common 15% of our genes. Junk DNA.
Not retrotransposons. repetitive sequences. Used for DNA fingerprinting.
3.8 bya
3.5 bya
1.5 bya
In between
600 mya
Films containing carbon
Cyanobacteria release O2 into air
First eukaryote fossils.
Mitochondrial evolution and OXIDATIVE PHOSPHORYLATION
First animal fossils