Characters and Character States: The cladogram in Figure 6 has a few shared feat
ID: 165794 • Letter: C
Question
Characters and Character States: The cladogram in Figure 6 has a few shared features of particular groups marked on it. We refer to features or traits of organisms as characters. A character can be any trait including the morphological traits shown below. Molecular and behavioral characters are commonly used, in addition to morphological characters. Characters useful for phylogenetic analyses must have some variation such that they come in different character states. Characters states include "present" and "absent" as well as variable conditions such as size. The character "leg length" shows two states (long and short in Figure 6. The character states may be marked on the tree, as shown for head crests and legs, or indicated by numbers, with a key to the numbers presented elsewhere. Marking a character onto a particular position on a cladogram indicates that the feature originated at this point in time and was passed to all the descendants of the lineage after this point, unless otherwise noted. For example, the character state "long legs" originated in the lineage between S and Land was passed to all descendants. Assume that the numbers from 4 to 9 in Figure 6 represent the evolution of particular characters. Which of the numbered features is present in taxon E Which taxon or taxa share characters 6 and 7? Which taxon or taxa share characters 6 and 5? Which of the numbered features is present in taxon H Taxon A is marked as having a head crest, but taxa E, F, and H also have a crest on their heads. These taxa are distributed across the cladogram with taxon A shown a more closely related to taxa B and C, than to E, F, and H.Explanation / Answer
In this cladogram as we move from A to H the taxa get more derived. Meaning each taxa as we move from A to H will have something new or different from what is seen in the previous group.
4. Taxon E will have features 9, 7 and 6. Reason-The features 6 and 7 originated in the lineage between S and O. E is a descendant after 6 and 7 originated.The feature 9 originated in the lineage between O and E. Hence, E will contain number features 9,6 and 7 as they originated before E.
5. Features 6 and 7 will be present in taxa E, F, G and H. Reason :Taxa E, F, G and H are descendants after the origin of feature 6 and 7 , hence these taxa will have both these features
6.Taxon D shows 6 and 5. Reason: The character 6 originated in the lineage between D and S and feature 5 originated (the alphabet behind 6 is not clear, I have assumed it to be P) in the lineage between P and D . Hence the taxon D being the only descendant after the origin of 5, D is the only taxon that will exhibit features 6 and 5.
7. Taxon H will have features 6 and 7 only. Reason: the number features 6 and 7 originated in the lineage between S and O. Additionally taxon H is one of the descendants. Moreover there are no other number feature that originated in the lineage between O and H . Hence only features 6 and 7 are present in taxon H.