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from the USAD glossary 2008-2009


life from nonliving material


characteristic that affords an organism greater fitness

adaptive radiation

evolutionary diversificiation into several different populations


different versions of the same gene


occuring in distinctly seperate locations

allopatric speciation

geographically mediated species formation

amniotic egg

egg w/ compartmentalized sacs that allowed vertebrates to reproduce on land

analogous structures

similar features from common environments

binomial nomenclature

developed by Linnaeus; first term genus, second term species


explaining the ecological and historical reasons for the observed geographic distributions of organisms


double-stranded DNA molecule, contains a series of genes


group of organisms that share a most recent common ancestor; "monophyletic group"


method of phylogeny reconstruction and system of classification that groups organisms according to the explicit definition of uniquely shared and derived characteristics


branching/bifurcating diagram; shows evolutionary relationships; depicts points where species diverged

common ancestor

real or hypothetical taxon from which two evolutionary lineages are directly descended


two matched sets of chromosomes, therefore, two sets of geenes in nucleus

direct fitness

how many alleles a genotype contributes to next generation's gene pool


deoxyribonucleic acid; nucleotides in a double helix; controls inheritance

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