Question

A new organism is discovered in the forests of Costa Rica. Scientists there determine that

the polypeptide sequence of hemoglobin from the new organism has 72 amino acid
differences from humans, 65 differences from a gibbon, 49 differences from a rat, and 5
differences from a frog. These data suggest that the new organism
A) is more closely related to humans than to frogs.
B) is more closely related to frogs than to humans.
C) may have evolved from gibbons but not rats.
D) is more closely related to humans than to rats.
E) may have evolved from rats but not from humans and gibbons.

Answer 1

B. Is more closely related to frogs than to humans.

Step-by-step explanation:

The amount of changes observed in a given gene from two different species is directly proportional to the divergence time. This means that if two species diverged recently, there will be few differences because there hasn't passed enough time for them to accumulate mutations. If two species diverged a long time ago, you will be able to observe many differences between the two homologous genes. The shorter the divergence time between two species, the closer they are related. Knowing this, you can conclude that the new organism will be more closely related to the species that it is more similar to, and in this case, that species is the frog, that only shows 5 differences in the hemoglobin when it's compared to the new species.