RQ20-Speciation

What criterion does the biological species concept use to identify species?

 

reproductive isolation

strength of the biological species concept?

 

It is focused on genetic isolation—the key to speciation,

Weakness of the biological species concept?

 

It isn’t applicable to asexual, fossil, or geographically isolated species

Why is the morphological species concept a logical criterion for identifying species?

 

If species are evolving independently, they should have recognizable morphological differences

strength of the morphospecies concept?

 

It can be used with fossil or asexually reproducing species, as well as sexually reproducing species.

weakness of the morphospecies concept?

 

Experts can disagree about whether populations are similar enough to be the same species.

Why is genetic isolation--meaning, a lack of gene flow--required for speciation to occur?

 

Otherwise, gene flow will prevent populations from diverging (keep them alike).

What is a phylogenetic species?

 

The smallest monophyletic group on a tree of populations.

What is vicariance?

 

A physical event that splits a population into two geographically isolated groups.