Question

biology (2018) / section 1 / 44 of 55
unknown species
key
= species 1 = species 2 = species 3
= species 4 = species 5
which statement accurately describes the age range of the unknown species?
a. it existed in age range w because it appears in the core sample with species 2.
b. it existed in age range x because it appears in the core sample after species 2 but bef species 3.
c. it existed in age range y because it existed in the same period as both species 2 and
d. it existed in age range z because it existed at the same time as species 5.
age ranges
w
x
y
z
older

Explanation:

Step1: Analyze the core sample and species distribution

The unknown species is in a layer with Species 2, 3, and others. We need to check the age ranges (W, X, Y, Z) and which species co - exist.

Step2: Evaluate Option A

Species 2's age range: From the right graph, Species 2 is in a range that doesn't match W (since W is a different layer). So A is incorrect.

Step3: Evaluate Option B

The unknown species is not after Species 2 and before Species 3 in terms of age range. The co - existing species don't support this. So B is incorrect.

Step4: Evaluate Option C

The unknown species is in the same layer as Species 2 and Species 4 (from the core sample and the key). The age range Y has the overlap of Species 2 and 4's existence. So this is correct.

Step5: Evaluate Option D

The unknown species is not in the same layer as Species 5. Species 5 is in a lower (older) layer. So D is incorrect.

Answer:

C. It existed in Age Range Y because it existed in the same period as both Species 2 and 4