Fossil Record

Question 1

Name patterns seen in the fossil record

Answer 1

anagensis, adaptive radiation, convergent evolution, and Dollo’s Law

Question 2

Anagenesis

Answer 2

• no branching
• evolutionary change within a single species lineage

Question 3

adaptive radiation

Answer 3

• many branches; often polytomy
• genetic adaptation to new environment that can lead to speciation

Question 4

convergent evolution

Answer 4

• independent evolution
• multiple points on a tree

Question 5

Dollo’s Law

Answer 5

• once lost, a trait is not regained

Question 6

Name rates seen in the Fossil Record

Answer 6

phyletic gradualism, punctuated equilibrium, a type of general continual DNA mutations

Question 7

Phyletic gradualism

Answer 7

• involves transitional fossils
• evolutionary change has occurred gradually and incrementally over the course of long time spans

Question 8

punctuated equilibrium

Answer 8

• hypothesis, most evolutionary change has occurred not gradually and incrementally over the course of long time spans (i.e., by anagenesis), but rather in newly formed species that originate by peripatric speciation
• Character evolution, they claimed, occurs in bursts (“punctuations”) associated with speciation

Question 9

What does continual DNA mutations have an effect on in rates seen in the fossil record?

Answer 9

• that many of these occur in the “background”, so there are no trait
  changes (equilibrium) unless the environment changes and then trait change
  occurs very quickly (punctuated)