Species and Macroevolution

Question 1

Describe how a species is characterized and the drawbacks of using morphological traits.

Answer 1

They are characterized by looking at their ability to interbreed, what their genetics tell them, where they’re found, what’s going on with their ecology, and looking at evolutionary relationships. The drawbacks of using morphological traits are the number of traits to consider, traits can vary, members of the same species can look very different, and members of different species could look very similar.

Question 2

The 4 species concepts

Answer 2

DNA sequences within genes, gene order along chromosomes, chromosome structure, and chromosome number.

Question 3

Define the 4 types of prezygotic isolation.

Answer 3

Habitat isolation, temporal isolation, mechanical isolation, and gametic isolation.

Question 4

Compare and contrast allopatric and sympatric speciation and give examples.

Answer 4

Allopatric speciation is the most prevalent method for cladogenesis, and occurs when some members of a species become geographically separated or isolated. Sympatric speciation happens when members of a species that are within the same range diverge into two or more different species even though there are no physical barriers interbreeding.

Question 5

Describe Hox genes and why they are so important to development and speciation.

Answer 5

Hox genes are master regulatory genes that are in charge of body plans for organisms when they are developing embryologically.