Chapter 24: Origin of Species

Question 1

speciation

Answer 1

1 species splits into 2

Question 2

microevolution

Answer 2

happens on a small scale (within a single population); change of allele frequency over many generations

Question 3

macroevolution

Answer 3

happens on a scale that transcends the boundaries of a single species

Question 4

Biological species concepts

Answer 4

a species taxon as a group of organisms that can successfully interbreed and produce fertile offspring

Question 5

Biological species concepts strength

Answer 5

Genetic link important for natural selection

Question 6

Biological species concept weakness

Answer 6

inapplicability to non-bisexual organisms and fossils

Question 7

Morphological species concept

Answer 7

relies on morphological data and emphasizes groups of physical traits that are unique to each species

Question 8

Morphological species concept strength

Answer 8

Applicable to fossils

Question 9

Morphological species concept weakness

Answer 9

How different do species need to be? (relies on subjective criteria)

Question 10

Ecological species concept

Answer 10

A species is a set of organisms adapted to a particular set of resources, called a niche, in the environment

Question 11

Ecological species concept strength

Answer 11

Clear link to natural selection

Question 12

Ecological species concept weakness

Answer 12

Hard to define a niche

Question 13

Phylogenetic species concept

Answer 13

The concept of a species as an irreducible group whose members are descended from a common ancestor and who all possess a combination of certain defining, or derived, traits

Question 14

Phylogenetic species concept strength

Answer 14

Links to evolutionary relationships

Question 15

Phylogenetic species concept weakness

Answer 15

How different do molecular signatures need to be in order to determine different species? Species or subspecies?

Question 16

Current view on species concepts

Answer 16

Combination of the concepts; biological species concept is probably the best

Question 17

Fitness

Answer 17

Success of offspring

Question 18

Allopatric speciation

Answer 18

also known as geographic speciation, is speciation that occurs when biological populations of the same species become isolated due to geographical changes such as mountain building or social changes such as emigration

Question 19

Sympatric speciation

Answer 19

a speciation process when two groups of identical species lived in identical geographical areas, they evolve in such a way that they could no longer interbreed

• reproductive or behavioral
• does NOT take place thru geographic isolation
• common in plants

Question 20

Polyploidy

Answer 20

Duplication of chromosomes

Question 21

The largest unit within which gene flow can readily occur

Answer 21

a species

Question 22

Genetic drift occurs in _____ populations

Answer 22

Small

Question 23

Sexual selection occurs in _____ speciation

Answer 23

Sympatric