In Figure 34.25, which of the following is the sister taxon to the archosaurs? (A) synapsids (B) crocodilians (C) turtles (D) lepidosaurs

Video transcript

Hi everyone. Let's look at our next problem. It says the figure below shows the fila ginny of am notes and were given a philo genetic tree with an ancestral amnesia at the top. Then it says identify the incorrect statement about the file a genie of ambiance. And when we look over our answer choices were given different species in each choice and statements about their relationships based on this tree. So remembering that we're looking for the statement that is incorrect. So let's look at our choices. We'll start with choice a squab mates. So let's find squad mates on our tree. Let's highlight it here and two guitars come here share Lepidus Ors as their most recent common ancestor. So highlight lepidus or as we see them higher up here and when we trace the relationship here we see that indeed squab mates and Tatars. The pity sources, the next branch up as their most recent common ancestor. So that is a true statement. So therefore that cannot be our answer since we're looking for an incorrect statement. So let's move onto Choice B. Choice B says crocodiles are the sister group of our case. Ors so we see that our case Ors are an ancestor of crocodiles, one of the branches coming from our shores. So we would say yes that is correct. Crocodiles are one of the groups descended from RK stores one of the sister groups. So that is true and we will eliminate choice B. Now let's go on to choice C. Choice C says mammals down here arose from the synapse it's and yes, we see this line directly from synapses to mammals, showing that mammals did originate from synapse. It's so another correct answer. Another true answer. And they're, sorry, another true statement and therefore not our correct answer. So now we've just got one left choice D. And that is dinosaurs. Find them over here originated from the Lepidus Ors. Well we can see from our fill a genetic tree that dinosaurs and Lepidus Orr's dinosaurs did not descend from Lepidus Ors instead if we trace back up their sister groups descended from a common ancestor that Diop sides. So dinosaurs not descended from dinosaurs but instead they are sister groups from the common from the ancestor die upsides. So that is an incorrect or false statement and therefore that is our correct answer. So Choice D dinosaurs originated from Lepidus Ors is an incorrect statement about the fila ginny of am notes. See you in the next video