(Ch.9)

Question 1

What is a Homologous Trait?

Answer 1

This trait is shared between two or more organisms because the common ancestor of these organisms also had this trait.
(ex. the common ancestor of apes and humans had opposable thumbs)

Question 2

What is an Analogous Trait?

Answer 2

This trait is shared between two or more organisms because of convergent evolution to environmental factors.
(ex. Fish and dolphins both have fins and tails but very different ancestry)

Question 3

What is an Ancestral Trait? Give an example.

Answer 3

This trait hasn’t changed much/at all since it first evolved in a distant ancestor.
(ex. Tails in monkeys)

Question 4

What is a Derived Trait? Give an example.

Answer 4

This trait has changed more recently in a subgroup of a species.
(ex. Apes evolved to no longer have tails)

Question 5

How is the Scientific Naming of species formatted? Give an example.

Answer 5

Scientific naming is formatted [genus] [species] [sub-species]
(ex. Homo sapiens sapiens)
(ex. H. sapiens sapiens)-but in italics

Question 6

Differentiate between
1. Unique Derived Traits
2. Shared Derived Traits

Answer 6

1. Unique derived traits are newer traits specific to one species.
2. Shared-derived traits are newer traits that can be seen in multiple species.

Question 7

What is a Cladogram? What does it emphasize?

Answer 7

1. A Cladogram has a single primary line that shows the relations of multiple species to a single common ancestor.
2. They emphasize derived TRAITS during classification.

Question 8

What is a Phylogenetic Tree? What does it emphasize?

Answer 8

1. A Phylogenetic Tree is called so because it branches, showing the evolutionary relationships between species.
2. They emphasize evolutionary relationships.