11.07 Imperfection of the fossil record

Question 1

Gradualistic change

Answer 1

• Darwin expected
• Lineages constantly evolving
• Intermediate forms.

Question 2

Punctuated Equilibrium.

Answer 2

• Stasis
• Abrupt intervals of change.

Question 3

Random walk

Answer 3

• Process model that predicts change over time.
• Introduces random change in each time increment.

Question 4

What is a Haldane?

Answer 4

• Measurement of change relative to variability.
• 1 Haldane is a change of 1 standard deviation in 1 generation.

Question 5

What does the prevalence of stasis in the fossil record suggest?

Answer 5

• Populations adapt very quickly to change and that stabilizing selection (or fast directional selection) is common.

Question 6

Where are organisms most likely to end up as fossils?

Answer 6

Organisms with hard parts living in shallow seas deposited on continents.

Question 7

How is perfection of the fossil record measured.

Answer 7

fossils found / things that were alive at that time.

Question 8

How imperfect are paleontological collections?

Answer 8

Globally: Around 2%, Darwin was right, small number.

Locally: can be very complete (0 - 100%).