1macroevolution
large changes over a very long period of time
2speciation
splitting of one species into two or more new species
3What is a species?
they interbreed and share a gene pool, each species in some way is reproducitvely isolated from another species
4What are the differences between pre and post-zygotic barriers?
Prezygotic barriers act before fertilization, preventing the formation of a zygote, while postzygotic barriers occur after fertilization, reducing the fitness of hybrid offspring
5What is the term for speciation that involves a physical or geographical barrier?
allopatric speciation
6What is the term for speciation that involves sexual selection?
sympatic speciation
7How is adaptive radiation related to the bottle neck or founder effect?
adaptive radiation is a evolutionarily rapid change between populations sometimes caused by the bottle neck or founder effect
8reproducitve barriers
isolating mechanisms that prevent successful reproduction from occurring
9prezygotic
before formation of a zygote
10Name the ways for speciation to occur
habitat isolation, temporal isolation, behavioral isolation, mechanical isolation, gamete isolation
11habitat isolation
species live in different areas or geographical ranges
12temporal isolation
mating seasons differ
13behavioral isolation
different mating behaviors
14mechanical isolation
sexual reproductive organs do not 'match'
15gamete isolation
gamete can not fuse
16postzygotic
after formation of a zygote
17zygote mortality
egg unable to divide or embryo unable to develop
18hybrid sterility
a baby is born, but is infertile (like w/ the mules)
19F2 fitness
the second generation is infertile
20What are the models of speciation?
allopatric and sympatric
21allopatric
speciation based on geographic isolation
22sympatric
population develops into 2 or more reproductively isolated groups without geographic isolation
23adaptive radiation
new species evolve from a single ancestral species
24How old is the Earth?
4.6 billion years old
25How long ago do scientists think unicellular and multicellular organisms evolved?
3.5 billion years ago
26What are the five main causes of extinction?
continental drift, volcanic activity, climate change, large meteorites, and humans
27How do the continents move?
plate tectonics, separation of land masses
28fossils
traces and remains of past life or any other direct evidence of past life
29paleontology
science of discovering and studying the fossil record and making decisions about the history of species
30systematics
study of evolutionary history of life on Earth
31phylogeny
evolutionary history of a group of organisms
32taxonomy
identifying, naming, and classifying organisms
33What is a phylogenetic tree?
diagram that indicates common ancestors and lines of descent
34What two main pieces of evidence help scientists construct a phylogenetic tree?
comparative anatomy (homologous structures) and molecular data (DNA and amino acid comparisons)
35morphological data
homologous structures are related to each other through common descent
36What does each node or branching point signify?
speciation
37molecular data
the more closely related species are, the more similar their DNA