Warm-up: Reviewing Speciation

The formation of a new species is called...

• Speciation

• Natural Selection

• Gene Flow

• Mutation

• Genetic Drift

There are two main types of speciation, based on the factors that cause it. In ____ speciation, a physical barrier keeps the populations from interbreeding and mixing gene pools.

• Sympatric

• Allopatric

• Convergent

• Divergent

There are two main types of speciation, based on the factors that cause it. In ____ speciation a NON-physical barrier keeps the populations from interbreeding and mixing gene pools; it could be behavioral, due to difference in habitat preferences, or even due to their offspring not being viable.

• Sympatric

• Allopatric

• Convergent

• Divergent

A form of speciation in which species evolve from a single ancestral species while inhabiting the SAME geographic region (without physical separation:

• Divergent Speciation

• Sympatric Speciation

• Complex Speciation

• Allopatric Speciation

A population of orcas live in the same habitat but a subset of the population are beginning to avoid the other parts of the population and not interbreed with those members. It appears this group has a different courtship ritual and social structure. Overtime these two populations may become separate species. What type of speciation is this?

• Allopatric

• Convergent

• Complex

• Sympatric

A population of arboral rat lives in the trees of a tropical island.  A volcano erupts and the lavaflow splits the forest. Even after it cools, there is nearly a mile of desloate black-rock between the two parts of the forest. Some of the rat population is on one side of the forest. Some are on the other. If enough time passes, if mutations occurs, and if there are different selective pressures, these two populations may become different species. If they do it, it is the result of...

• Temporal isolation

• Simple Speciation

• Complex Speciation

• Sympatric Speciation

• Allopatric Speciation

The emergence of a major highway through a nature reserve may lead to ____

• sympatric speciation

• behavioral isolation

• temporal isolation

• allopatric speciation

Sympatric speciation can be caused by a number of factors that isolates one population from another and can cause two distinct species to form (even when they are not physically separated). Prezygotic barriers and aspects of a population that keep the populations from even breeding with one another. They include:

• temporal isolation (like two frog populations that breed in different seasons)

• habitat isolation (like two bird populations- each with a preference for different types of trees)

• behavioral isolation (like bird populations having different songs to attract mates)

• All of these

Two frog populations live in the same general area (are not separated by any physical barrier) do not mate because one prefers to be in the moving water, while the other prefers to stay in still water. Eventually they may become distinct species due to:

• Sympatric speciation: Habitat Isolation

• Allopatric speciation: Behavioral Isolation

• Sympatric speciation: Behavioral Isolation

• Allopatric speciation: Habitat Isolation

• Sympatric speciation: Post-Zygotic Barrier

Sometimes two populations will interact, but are already different enough that even if they reproduce, their offspring will either: not develop fully and will not be born; or be born, but not surive long after birth; or be born but will be infertile and unable to reproduce. These are examples of...

• pre-zygotic barriers

• temporal isolation

• allopatric speciation

• post-zygotic barriers