Chapter 22- Species and Speciation

Question 1

What is speciation?

Answer 1

The process that produces new and distinct forms of life.

Question 2

What is a species?

Answer 2

A fundamental evolutionary unit that is fluid and capable of changing, giving rise through evolution to new species - SPECIES ARE NOT FIXED

Question 3

How do we determine whether or not individuals are members of the same species?

Answer 3

By determining their ability or inability to exchange genetic material by producing fertile offspring.

Question 4

What is the Biological Species Concept?

Answer 4

That species are groups of actually or potentially interbreeding populations that are reproductively isolated from other such groups. - Reproductive compatibility, and that compatibility must be FERTILE - not sterile (ex: horse and donkey produce a mule, which is sterile, so they cannot be part of the same species)

Question 5

What is a downfall of the BSC?

Answer 5

• It’s difficult to apply - how do we know if certain species that look alike can’t interbreed if they are geographically separated? Or if their offspring are fertile?
• Doesn’t include asexual reproducers
• What do we do about extinct species?
• ring species- species that indirectly exchange genetic material

Question 6

What is the Morphospecies Concept and why is it useful? What are its downfalls?

Answer 6

It states that members of the same species usually look alike and cluster biologically.
Downfalls:
-some species don’t look alike through polymorphisms in phenotype, old vs young, gender
-Some different species look the same (horses and donkeys)