Chapter 14 Key Words

Question 1

Macroevolution

Answer 1

Large-scale evolutionary change

Question 2

Species

Answer 2

A distinct type of organism

Question 3

Biological species

Answer 3

A population, or group of populations whose members are interbreed & produce fertile offspring

Question 4

Speciation

Answer 4

Formation of new species

Question 5

Reproductive Barrier

Answer 5

Mechnasim that prevents groups of organisms from sharing a gene pool

Question 6

Prezygotic reproductive barrier

Answer 6

Separation of species due to factors that prevent the formation of a zygote

Question 7

Ecological isolation

Answer 7

A difference in habitat preference can separate 2 populations in the same geographical area

Question 8

Temporal isolation

Answer 8

2 species that share a habitat will not mate if they are active at different times of day or reach

Question 9

Behavioral Isolation

Answer 9

Behavioral difference may prevent 2 closely related species from mating

Question 10

Mechanical isolation

Answer 10

In many animal selection male & female parts fit together almost like a key in a lock

Question 11

Gametic isolation

Answer 11

If sperm cannot fertilize an egg cell then no reproduction will occur

Question 12

Hybrid infertility (sterility)

Answer 12

Some hybrid are infertile

Question 13

Postzygotic reproductive barrier

Answer 13

Separation of species due to selection against hybrid offspring

Question 14

Hybrid inviability

Answer 14

A hybrid embryo may die before reaching reproductive maturity, typically bc the genes of its parents are incompatible

Question 15

Hybrid breakdown

Answer 15

Some species produce hybeid offspring that are fertile

Question 16

Hybrid

Answer 16

The offspring of indiv. of 2 diff. species

Question 17

Allopatric speciation

Answer 17

Formation of new species after a physical barrier separates a population into groups that cannot interbreed

Question 18

Parapatric speciation

Answer 18

Formation of new species when part of a population enters a habitat bordering the parent species range & the 2 groups become reproductively isolated

Question 19

Sympatric Speciation

Answer 19

Formation of a new species within the habitat boundaries of a parent species

Question 20

Polypoid cell

Answer 20

Cell w/ extra chromosome sets

Question 21

Gradualism

Answer 21

Theory that processes that evolutionary change occurs gradually, in a series of small steps

Question 22

Adaptive radiation

Answer 22

Divergence of multiple new species from a single ancestral type in relatively short time

Question 22

Punctuated equilibrium

Answer 22

Theory that life’s history has been characterized by Burt’s of rapid evolution interupting long periods of little change

Question 23

Background extinction rate

Answer 23

Steady, gradual loss of species through natural competition or loss of genetic diversity

Question 24

Mass extinctions

Answer 24

The disappearance of many species over realitivty short expanses of time

Question 25

Impact theory

Answer 25

Idea that mass extinctions were caused by impacts of extraterrestrial orgin

Question 26

Taxon

Answer 26

A group of organisms at any rank in the taxonomic hierachy

Question 27

Phylogenetics

Answer 27

Depict relationships based on descent from shared ancestors