Chapter 13- Speciation

Question 1

Species are the smallest possible groups who members are descended from a common ancestor and who all possess defining or derived characteristics that distinguish them from other such groups

Answer 1

Phylogenetic Species Concept

Question 2

Species are groups of actually (or potentially) interbreeding natural populations that are reproductively isolated from other such groups

Answer 2

Biological Species Concept

Question 3

A group of spatially separated populations of the same species that interact at some level (e.g., exchange alleles).

Answer 3

Metapopulation

Question 4

Species are metapopulations of organisms that exchange alleles frequently enough that they comprise the same gene pool, and therefore, the same evolutionary lineage.

Answer 4

General Lineage Species Concept

Question 5

An aspect of the environment, genetics, behavior, physiology, or ecology of a species that reduces or impedes gene flow from individuals of other species. This can be geographic or reproductive.

Answer 5

Isolating Barrier

Question 6

The evolutionary process by which new species arise. It causes one evolutionary lineage to split into two or more lineages (cladogenesis).

Answer 6

Speciation

Question 7

Occurs when populations are in separate, non-overlapping geographic areas (i.e., they are separated by geographic barriers to gene flow).

Answer 7

Allopatry

Question 8

Occurs when populations are in the same geographic area.

Answer 8

Sympatry

Question 9

Occurs when sperm or pollen from one species fails to penetrate and fertilize the egg of another species.

Answer 9

Genetic Incompatibility

Question 10

Occurs when reproductive barriers prevent or strongly limit reproduction between populations. The result is that few or no genes are exchanged between the populations.

Answer 10

Reproductive Isolation

Question 11

Occurs when sperm or pollen from one species fails to penetrate and fertilize the egg of another species.

Answer 11

Gametic Incompatibility

Question 12

Aspects of the genetics, behavior, physiology, or ecology of a species that prevent fertilized zygotes from successfully developing and reproducing themselves.

Answer 12

Post-zygotic Reproductive Barriers

Question 13

Aspects of the genetics, behavior, physiology, or ecology of a species that prevent sperm from one species from fertilizing eggs of another species. These reduce the likelihood that a zygote will form.

Answer 13

Pre-zygotic Reproductive Barriers

Question 14

The increase of reproductive isolation between populations through selection against hybrid offspring.

Answer 14

Reinforcement

Question 15

Populations that live nearby are genetically more similar to each other than populations that live farther apart.

Answer 15

Isolation by Distance

Question 16

A connected series of populations (each of which can interbreed with its neighboring populations) that have diverged sufficiently across their ranges so that the populations at the ends of the series are too different to interbreed.

Answer 16

Ring Species

Question 17

The evolution of reproductive barriers between populations by adaptation to different environments or ecological niches.

Answer 17

Ecological Speciation

Question 18

Polyploidy (more than two paired chromosomes) resulting from interspecific hybridization.

Answer 18

Allopolyploidy

Question 19

Polyploidy arising within a species

Answer 19

Autopolyploidy

Question 20

Groups of organisms that are genetically distinct and do not interbreed, but are morphologically almost indistinguishable.

Answer 20

Cryptic Species