Based on the phylogenetic tree in Figure 28.2, which of the following statements is correct?
a. The most recent common ancestor of Excavata is older than that of SAR.
b. The most recent common ancestor of SAR is older than that of Unikonta.
c. The most basal (first to diverge) eukaryotic supergroup cannot be determined.
d. Excavata is the most basal eukaryotic supergroup.

Question

Based on the phylogenetic tree in Figure 28.2, which of the following statements is correct?

a. The most recent common ancestor of Excavata is older than that of SAR.

b. The most recent common ancestor of SAR is older than that of Unikonta.

c. The most basal (first to diverge) eukaryotic supergroup cannot be determined.

d. Excavata is the most basal eukaryotic supergroup.

Accepted Answer

Hi everyone, Welcome back. Let's look at our next problem. It says red algae, green algae and plants are included in the super group of you carry outs. Let's call from a condom video that these three things. Red and green algae and plants are included in the arche pallas dada group or a super group. I should say that is gonna be our answer. Um, but to understand why the other choices aren't correct, I'm just going to put up a fila genetic tree of the you carry outs um kind of involving a lot of the protests when you often study this because protests of that sort of lumped together group of every you carry out, that's not a plant animal or fungi. So here's our group of interest are keep last to appear and where it comes off. So our little guys come off from here. But let's look for other answer choices. Uh we have a choice A SAR and here's our SAR group and it gets its name. It's an acronym. It's right here from the members of its group, stamina files, Violetta and Rosaria. These are protease kind of famous collated protests. Um, but while plants come off from this other branch from star, they are not on the same branch of the phyllo genetic tree. So not in the same supergroup and wil eliminates our choice B is unique. Conta. And you're gonna notice when we look at our tree that yuna. Conta is not listed on here. And that's because you know, conta is an older term. It's now been replaced by this one right here and more fia so unique. Conta would be here. But sometimes in older sources are older textbooks. You might see you know Conta and you might see that particularly because you know Conta is the supergroup that ends up down the line here through the episode. Conta leading to the fungi and the animals. So that super group is kind of famous for lack of a better word because we lead on down here many different lineages which are protease, but it also includes fun giant animal leah plants you see are by themselves up here. So it's kind of interesting. You got fungi and animals down together off the unique conta or a morphy a branch and plants up off here. But you know, conta is not our correct answer. As we said, choice. Crk placenta is the group they come from. And finally we've got choice d excavator to well there, this sort of branch by themselves of you carry outs. They are single celled eukaryotes that have a feeding groove along one side. It's like the group is excavated from the cell which is where the name comes from. Um but not what our plants and algae are descended from. So not the correct answer. So again, red algae, green algae and plants are included in this super group of you carry outs and its choice E. R. Key plastic. See you in the next video

Verified video answer for a similar problem:

Key Concepts

Phylogenetic Tree

Eukaryotic Supergroups

Most Recent Common Ancestor