Question

exit ticket -- u4.l3: changes over time

1. during the past 100 years, the average temperature of the earth has increased by.8°. scientists expect it to continue to increase over the years in the future as well. how do you expect animals to evolve over the next several hundred years, based on this evolutionary pressure?

a. they will grow larger
b. they will grow smaller
c. they will grow thicker fur coats
d. they will grow thinner fur coats
time
(image of four evolutionary stages of a turtle-like organism labeled (a), (b), (c), (d) with a time arrow)

1. the image above shows the evolution of the modern day turtle. what evolutionary pressure probably lead the organism labeled “(a)” to evolve into the organism labeled “(c)”? explain your answer.

(blank lines for answer)

Explanation:

Question 1

The Earth's temperature is increasing. Thicker fur coats (option c) would be bad in warmer temps, and size (a, b) isn't directly tied to temperature increase. Thinner fur coats (d) help animals cool down in a warmer climate, so this is the adaptive evolution.

Looking at the evolution from (a) to (c), the organism develops a thicker, more protective shell. A likely evolutionary pressure is predation. Organisms with better protection (like a thicker shell) from predators would survive and reproduce more, leading to this evolution. So predation pressure (or the need for better defense against predators) probably drove (a) to evolve into (c).

Answer:

d. they will grow thinner fur coats

Question 2