(For Final) Chapter 16: The Origin Of Species

Front 1

Species

Back 1

A group of populations that evolves independently.

Front 2

The Biological Species Concept

Back 2

Defines a species as members of populations that actually or potentially interbreed in nature, not according to similarity of appearance.

Front 3

Isolating Mechanisms

Back 3

The traits that prevent interbreeding and maintain reproductive isolation. Provide a clear benefit to individuals.

Front 4

Premating Isolating Mechanisms

Back 4

The mechanisms that prevent mating between species.

Front 5

Geographic Isolation

Back 5

Prevents interbreeding between populations that do not come into contact because they live in different, physically separated places.

Front 6

Ecological Isolation

Back 6

When two populations that use different resources may spend time in different habitats within the same general area.

Front 7

Temporal Isolation (Time-Based Isolation)

Back 7

When two species occupy similar habitats, they cannot mate if they have different breeding seasons.

Front 8

Behavioral Isolation

Back 8

Signals and behaviors that differ from species to species that can prevent mating with members of other species.

Front 9

Hybrids

Back 9

Offspring of parents of different species. Offspring of parents of two different species.

Front 10

Mechanical Incompatibilities

Back 10

A reproductive isolating mechanism that aries when differences in the reproductive structures of two species make the structures incompatible and prevent interbreeding.

Front 11

Postmating Isolating Mechanisms

Back 11

Mechanisms that prevent the formation of vigorous, fertile hybrids between species.

Front 12

Gametic Incompatibility

Back 12

A postmating reproductive isolating mechanism that arises when sperm from one species cannot fertilize eggs of another species.

Front 13

Hybrid Inviability

Back 13

A postmating reproductive isolating mechanism that aries when hybrid offspring fail to survive.

Front 14

Hybrid Infertility

Back 14

A postmating reproductive isolating mechanism that arises when hybrid offspring are sterile or have low fertility.

Front 15

Speciation

Back 15

The process by which new species form.

Front 16

Allopatric Speciation

Back 16

Two populations are geographically separated from one another.

Front 17

Parapatric Speciation

Back 17

The relationship between organisms whose ranges do not significantly overlap but are immediately adjacent to each other; they only occur together in a narrow contact zone.