Animation Description
In the graphic that accompanies this multiple choice question, images of seven animals, shark, tuna, frog, human, hare, caiman, and parrot, are connected by a branching evolutionary tree beneath them. An arrow shows that time progresses in the upwards direction on the tree. On the tree, starting from the root, the branch leading to the shark splits off first to the left, then the branch leading to the tuna splits off to the left, and then the branch leading to the frog splits off to the left. Then a branch splits off to the left that itself splits into two, leading to the human and hare. The last branch, which extends up and to the right splits into the caiman and parrot branches. The hare, caiman, and parrot images are highlighted. When "a) hares" is clicked, red highlighting appears on the branches that connect the hare to the caiman. That highlighting travels down from the hare, through the common ancestor of humans and hares, and down from the caiman, through the common ancestor of caimans and birds, to the branching point beneath. The reader is instructed to "try again." When "b) parrots" is clicked, several highlighted items appear on the tree. Red highlighting calls out the two short branches that connect the caiman to the parrot, and this is labeled "distinct histories." An orange dot appears on the tree at the point where the two red highlighted lineages meet each other. This dot is labeled "common ancestor." Purple highlighting appears beneath, which traces a path on the tree from that common ancestor all the way to the root of the tree, passing through other branching points on its way to the root. The purple highlighted area is labeled "shared history."
Animation Text
Panel 1
Look at the lineages of the three animals that are highlighted. Which is more closely related to caimans — hares or parrots?
a) Hares
b) Parrots
Panel 2
Incorrect answer: Oops. Trace the caiman and parrot lineages to see if they are more closely related. Try again.
Panel 3
Correct answer: Good job! As you can see, caimans and parrots share a more recent common ancestor, so they are more closely related.