Exam 21: Reconstructing and Using Phylogenies

Which statement about the molecular clock is true?

A major disadvantage of maximum likelihood methods is that they

Refer to the figure showing a single viral plaque that was split every 400 generations and grown in the presence of a mutagen. Based on the figure, lineage A and lineage F are separated by _______ generations of evolution.Remember that evolution is occurring in both lineages.

Refer to the phylogenetic tree. All clades are subsets of larger clades.The most inclusive clade in the figure is _______; the least inclusive clade includes the _______.

Traits that are similar in different species for reasons other than a shared common ancestor are known as _______.

Tomatoes are in the genus Solanum.The family in which this genus belongs is named after it.Hence, tomatoes are in the _______ family.

Four different phylogenetic trees of a group of salamanders have been proposed.Trees A and B each require 12 homoplasies, but tree A requires 14 synapomorphies and tree B requires 13 synapomorphies.Tree C requires 15 homoplasies and 13 synapomorphies.Finally, tree D requires 10 homoplasies and 15 synapomorphies.According to the principle of parsimony, which tree(s) is/are the most accurate?

The table shows the number of DNA sequence changes between different fish lineages along with the divergence time. Of the three genes, gene _______ is evolving in a way closest to what would be expected under the molecular clock hypothesis.

The antifreeze proteins found in fish that live in very cold waters of the Arctic and Antarctic have evolved independently.The common ancestor of these fishes did not have the antifreeze proteins.Based on this information, which statement is true?

Suppose researchers know that two species of crab began diverging from a common ancestor when they were separated by the formation of the Isthmus of Panama 6 million years ago.The genetic divergence between these two species at the hypothetical R6 gene is 12 percent.This rate of evolutionary change at this gene in these species is _______ percent per million years.

Which of the following is the largest (most inclusive) taxon?

Drosophila yakuba and D.santomea are each other's closest relatives.Therefore, they are considered _______ species.

Refer to the diagram below showing a single viral plaque that was split every 400 generations and grown in the presence of a mutagen. The lineage that would be most likely to share the fewest synapomorphies with lineage A is the _______.

Consider four species of conifers.Species A and B are sister species.Species C and D are also sister species.The clade containing species A and B is a sister to the clade containing species C and D.Not counting the root as a node, how many nodes would be found in a phylogenetic tree of species A, B, C, and D?

The common ancestor of humans and the other great apes walked on all fours, while humans are bipeds.Bipedalism in humans is thus a(n) _______ trait.

Flies have only a single pair of functional wings, but their ancestors had two pairs of wings.Thus, having two pairs of wings is a(n) _______ trait.

Which of the following is the smallest taxon?

Which source of molecular data would be most helpful for a study of the evolutionary relationships of closely related species of flies?

Refer to the phylogenetic tree below showing the phylogenetic relationships among eight species.Red dots show the appearance of derived traits. According to the phylogenetic tree, salamanders and mice share _______ of the listed synapomorphies.

Refer to the figure.Most classification systems are designed to reflect evolutionary relationships of organisms.This is also the case in this phylogenetic tree, where there are three groups (taxa) that have been classified: group 1 (red), group 2 (yellow), and group 3 (blue). Most classification systems are designed to reflect evolutionary relationships of organisms.This is also the case in this phylogenetic tree, where there are three groups (taxa) that have been classified: group 1 (green), group 2 (orange), and group 3 (blue). Which of the taxa in the diagram is monophyletic, and which is polyphyletic?