Skip to main content
Ch. 21 - Genomes and Their Evolution

Chapter 5, Problem 4d

(d)Primates and rodents diverged about 65 million years ago, and chimpanzees and humans diverged about 6 million years ago (see Figure 21.17). How many amino acid differences are there between the sequence for the mouse and the sequence for the chimpanzee, gorilla, and rhesus monkey? How many amino acid differences are there between the human se-quence and the sequence for the chimpanzee, gorilla, and rhesus monkey? Based solely on the numbers of amino acid differences occurring over these time periods, what might you hypothesize about the rate of evolution of the FOXP2gene? Based on the information in the chapter regarding the FOXP2 gene, is your hypothesis correct?

Verified Solution
Video duration:
2m
This video solution was recommended by our tutors as helpful for the problem above.
911
views
Was this helpful?

Video transcript

Welcome back. Here's our next question based on the given short amino acid segments of the fox P. Two gene, which of the following statements is true And were given four different species with a very short sequence of Amino assets from this Fox P two gene. And when we look over our answer choices briefly, we see that they all have to do with comparing to species and whether they are closely related. Now, important to note here, the questions is based on the given short amino acid segments. So we kind of want to put aside what we know about which species are more closely related. Um for instance, we've got human and chimpanzee on here, we know humans and chimpanzees are closely related. But the question is asking us just based on these segments of amino assets. So we're going to look at how close are those segments by how much do they differ? And the fewer differences they have look more closely, the animal would be based just on the sequence. So that's an important note here. So let's look at choice A choice A says the mouse and the chimpanzee are closely related. So let's highlight those two and compare their sequences and we see that in these segments, those sequences are identical. They have zero differences. Now, if I were on a test, um time's of the essence, I'm just gonna pick that and move on. You can't really get any closer than identical sequence but for the sake of thoroughness, we're gonna walk through these answers and just check them, make sure nothing's more correct. So I'm just gonna mark that as likely correct and move on. But again on the test I'd be choosing A. And keeping going Choice B says the mouse and the Z. Finch are closely related. So let's compare their sequences and we see that they have just one difference there at the end. So we'll note that down but again not as close as mouse and chimpanzee so we'll move on to Choice C. And Choice C. Gives us the chimpanzee and the Z finch are closely related. So we look at their sequences and they also differ just in that last amino acid. So one amino acid different. So finally we look at Choice D. Choice D asked us to look at humans and the Z. Finch. When we look at these two we see they differ actually by two amino acids, one in the middle there and one at the end. Put that down. So when we look at all our answer choices, we see that none of B, C. Or D. Is has fewer differences than choice. A mouse and chimpanzee with identical sequences. So our correct answer here again, based only on this amino acid sequences, the mouse and chimpanzee are closely related. See you in the next video