Ch 24

Front 1

macroevolution

Back 1

evolutionary change on a grand scale, encompassing the origin of new taxonomic groups, evolutionary trends, adaptive radiation, and mass extinction

Front 2

speciation

Back 2

origin of new species in evolution

Front 3

species

Back 3

group whose members possess similar anatomical chracteristics and have the ability to interbreed

Front 4

bioloical species concept

Back 4

the definition of a species as a pop or group of pops whose members have the potential in nature to interbreed and produce fertile offspring; also called sexual species

Front 5

prezygotic barriers

Back 5

a reproductive barrier that impedes mating between species or hinders fertilization of ova if interspecific mating is attempted

Front 6

postzygotic barriers

Back 6

any of several species isolating mechanisims that prevent hybrids produced by 2 different species from devloping into viable, fertile adults

Front 7

ecological species concept

Back 7

the idea that ecological roles (niches) definie species

Front 8

pluralistic species concept

Back 8

the idea that there is no universal explanation for the cohesion of indivs that make up species

Front 9

morphological species concept

Back 9

the idea that species are defined by measurable anatomical criteria

Front 10

genealogical species concept

Back 10

a species is a set of rogs with a unique genetic history

Front 11

sympatric speciation

Back 11

a mode of speciation occuring as a result of a radiacal change in the genome of a subpop, reproductively isolating the subpop from the parent pop

Front 12

adaptive radiation

Back 12

the emergence of numerous species from a common ancestor introduced into an environment, presenting a diversity of new opportunities and problems

Front 13

autopolyploid

Back 13

a type of polyploid speices resulting from 1 speices doublning its chromosome number to become tetraploid which may self fertilize or mate with other tetraploids

Front 14

allopolyploid

Back 14

a common type of polyploid species resulting from 2 different species interbreeding and combining their chromosomes

Front 15

punctuated equilibrium

Back 15

a theory of evolution advocating spurts of relatively rapid change followed by long periods of stasis

Front 16

exaptation

Back 16

a structure that evolves and functions in 1 enviromental context but that can perform additional functions when placed in some new environment

Front 17

allometric growth

Back 17

the variation in relative rates of growth of various parts of the body, which helps shape the org

Front 18

heterochrony

Back 18

evolutionary change in the timing or rate of devlopment

Front 19

paedogenesis

Back 19

the precocious development of sexual maturity in a larva

Front 20

homeotic

Back 20

any of the gnes that control the overall body plan of animals by controling the developmental fate of groups of cells

Front 21

species selection

Back 21

theory maintiaining that species living the longest and generating the greatest number of species determine the direction of major evolutionary trends