Evolution Flashcards

6479740861	Theory of Evolution	the best scientific explanation for both the unity and diversity of life; proposed by Charles Darwin	0
6479740863	evolution	change in allele frequency over time; process by which modern organisms have descended from ancient organisms (decent with modification)	1
6479740864	genetic equilibrium	situation in which allele frequencies remain constant; no evolution occuring	2
6479740865	natural selection	natures way of selecting the best a particular environment; also called survival of the fittest	3
6479740866	diversity	all of the different species on Earth	4
6479740867	variation	the differences within a single species	5
6479740868	species	group of similar organisms capable of interbreeding and producing fertile offspring	6
6479740869	speciation	formation of new species	7
6479740870	common ancestry	a group of organisms share common descent if they have a common ancestor	8
6479740872	fossil record	the geological record of organisms on earth that have been preserved in the rock in a chronological order (oldest on bottom); evidence of common ancestry	9
6479740875	homologous structures	structures that have different mature forms in different organisms but develop from the same embryonic tissues; evidence of common ancestry	10
6479740876	analogous structures	is a trait or an organ that appears similar in two unrelated organisms	11
6479740877	vestigial structure	a structure that an organism has that is no longer useful to it, but that they have this structure because a common ancestor to that organism found it useful	12
6479740878	fitness	ability of an organism to survive and reproduce in its environment	13
6479740879	adaptation	inherited characteristic that increases an organism's chance of survival	14
6479740880	mimicry	the similarity of one species to another which protects one or both	15
6479740881	camouflage	when an organism blends in with its environment for protection against predators	16
6479740884	divergent evolution (adaptive radiation)	process by which a single species or small group of species evolves into several different forms that live in different ways	17
6479740885	convergent evolution	process by which unrelated organisms independently evolve similarities when adapting to similar environments	18
6479740886	coevolution	the evolution of two or more interdependent species, each adapting to changes in the other	19
6479740888	punctuated equilibrium	pattern of evolution in which long stable periods (stasis) are interrupted by brief periods of rapid change	20
6479740890	gene pool	the sum of all the genes in an interbreeding population	21
6479740891	allele frequency	number of times an allele occurs in a gene pool	22
6479740893	single-gene trait	trait controlled by a single gene (ex: widow's peak in humans)	23
6479740894	polygenic trait	trait controlled by two or more genes (ex: skin color of humans)	24
6479740895	stabilizing selection	form of natural selection that occurs when individuals near the center of a distribution curve have higher fitness than individuals at either end	25
6479740896	directional selection	form of natural selection that occurs when individuals at one end of a distribution curve have higher fitness than individuals in the middle or at the other end of the curve	26
6479740897	disruptive selection	form of natural selection that occurs when individuals at both ends of a distribution curve have higher fitness than individuals near the middle	27
6479740898	reproductive isolation	the inability of a species to breed successfully with related species due to geographical, behavioral, physiological, or genetic barriers or differences	28
6479740899	behavioral isolation	form of reproductive isolation in which two populations have differences in courtship rituals or other types of behavior that prevent them from interbreeding	29
6479740900	geographic isolation	form of reproductive isolation in which two populations are separated physically by geographic barriers such as rivers, mountains, or stretches of water	30
6479740901	temporal isolation	form of reproductive isolation that occurs when members of two species occupy similar habitats, but breed at different times	31
6479740903	gene flow	is the transfer of alleles or genes from one population to another	32
6479740904	genetic drift	change in allele frequencies of a population due to chance or random events rather than by natural selection	33
6516723232	bottleneck effect	a change in the allele frequency following a dramatic reduction in the size of a population	34
6516728843	founder effect	change in allele frequencies as a result of the migration of a small subgroup of a population	35
6516737000	Hardy-Weinberg Principle	states that allele frequencies in a population remain constant unless 1 or more factors cause those frequencies to change	36
6516746196	sexual selection	when individuals select mates based on heritable traits	37