fossil record
using fossils and their structure to determine the evolution of an organism
biogeography
the geographic distribution of organisms on earth follows patterns that can be explained by evolution
relative dating
the method used to determine the approximate age of a structure based on is physical relationship to surrounding geologic structures
absolute dating
exact age is determined by measuring the physical properties of the object itself (ex. carbon dating)
embryology
compares and contrasts embryos of different species
embryos of different species can have similarities that are not visible when organisms are fully formed
molecular evolution
DNA, RNA, and amino acids show evolution through differences in their sequences
homologous structures
similar physical traits that come from a common ancestor that are used for different purposes
analogous structures
features in organisms that are similar in unrelated species, caused by similar selection pressures
vestigial structures
traits inherited that are no longer needed/don’t benefit the organism anymore
divergent evolution
two species originate from a common ancestor (contain homologous structures and molecular homology)
convergent evolution
two unrelated species evolve similar traits (contain analogous structures)
parallel evolution
two species evolve similar traits independently (live in different environments)
coevolution
evolution of one species due to the evolution of another
gradual evolution
evolution that occurs by the gradual accumulation of small changes
transitional species
species that exist from one species becoming another
punctuated equilibrium
species diverge in spurts of relatively rapid change
phylogeny
the evolutionary history of a species or a group of related species
systematics
a discipline focused on classifying organisms and determining their evolutionary relationship
studied through fossils, molecules, and genes
cladistic analysis
shared characteristics depicted in a diagram
phylogenetic tree
depicts evolutionary relationship and reflects taxonomic hierarchy over time
monophyletic taxon
includes all descendants and the common ancestor
polyphyletic taxon
does not have the common ancestor of the organisms
paraphyletic taxon
a common ancestor and some of the descendants are included, but not all
origin of life
3.5 to 4 billion years ago
life started with single cell bacteria
abiotic synthesis of organic monomers
miller & urey experiment
stimulated the chemical environment of primitive earth
produced a variety of molecules associated with life