Evolution

Based on the evidence in the diagram below, the taxon that lived the most recently is

• A

• B

• C

• D

A common ancestor for both species C and E could be at position number

• 1

• 2

• 3

• 4

The two extant species that are most closely related to each other are

• A and B.

• B and C.

• C and D.

• D and E.

When using a cladistics approach to systematics, which of the following is considered most important for classification?

• Shared primitive characters

• Analogous primitive characters

• Shared derived characters

• The number of homoplasy

Homologous structure

• Are found in animals that shares a common ancestor

• Share a common function

• Are no longer functional (vestigial )

• Are limited to vertebrate animals

The four-chambered hearts of birds and the four-chambered hearts of mammals evolved independently of each other. If one were unaware of this independence, then one might logically conclude that

• The birds were the first to evolve a 4-chambered heart.

• Birds and mammals are more distantly related than is actually the case.

• Early mammals possessed feathers.

• The common ancestor of birds and mammals had a four-chambered heart

Which of the following animals have wings that are not homologous to the others

• Ptersours

• Bat

• Insects

• Bird

Which of the five marks in the tree above corresponds to the most recent common ancestor of a mushroom and a sponge?

• a

• b

• c

• d

The tree below shows the phylogenetic relationships of seven taxa. Which of the following is NOT a clade (a group that includes a common ancestor and all of its descendants)?

• A+B + C

• B +C

• E+F

• B+C+E+F+G+H

Scientists found the fossilized remains of a mammal’s jaw and leg. What additional information do scientists need to hypothesize the age of the fossil?

• The rest of the skeleton

• The continent where the fossils were found

• A stratigraphic layer where the fossils were found

• The climate at the time the mammal died