Exam 21: Reconstructing and Using Phylogenies

The suffix "-idae" (as in "Sciuridae") refers to organisms of which kingdom?

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 is the best?

Which application of phylogenetic trees cannot be done without assuming a molecular clock?

Consider a phylogeny of metazoans.Snakes, which lack limbs, evolved from vertebrates that had legs.The limbs of snakes disappeared by _______, and the backbones of snakes are a _______.

Which statement about phylogenetic trees is false?

In the case where phylogenetic analysis of HIV was used to convict a physician of purposely injecting blood from his HIV-positive patient into his former girlfriend, which would be evidence that would most likely exonerate the physician?

Which event or situation would violate an assumption of the molecular clock?

Why are fossils useful for determining whether a trait is ancestral or derived?

Refer to the figure. Which synapomorphies are shared by lizards and salamanders?

Which statement about phylogenetic trees is false?

Drosophila mauritiana and D.melanogaster diverged 2 million years ago.Between these species, 40 nucleotide differences have accumulated at a gene.At that same gene, D.mauritiana and D.simulans have accumulated 8 nucleotide differences.Assuming that a molecular clock is operating, the best estimate for the divergence time between D.mauritiana and D.simulans is _______ years ago.

Which trait would be least useful in a phylogenetic analysis?

Males of a species of grasshoppers sing very rapid songs.Experimental evidence shows that females of this species prefer these fast songs over slowed-down songs.Related species have males that do not sing as fast, but interestingly, the females from these other species also prefer very fast songs over songs of males from their own species.These results are consistent with the _______ hypothesis.

Refer to the phylogenetic tree below showing the phylogenetic relationships among eight species.Red dots indicate the appearance of derived traits. The positions of which two taxa could be reversed without changing the meaning of the tree?

Several unrelated species of spiders have evolved social behaviors presumably in response to selective pressures brought on by high density.The closest relatives of these spiders lack these behaviors.These social behaviors are likely examples of _______ evolution, which is a form of _______.

Biologists are interested in determining the phylogenetic relationships of a group of beetles.Information about which of the following types of behavior would be least useful in reconstructing phylogenies?

Experimental evolution studies using bacteriophages have been most useful in showing that

In the experimental tests of phylogenetic reconstruction methods done by Hillis et al, the experimenters mimicked the levels of homoplasy commonly seen in real organisms by

The Lamiaceae is a ________ of _______.

The ratites are a group of flightless birds comprising ostrich, emu, cassowary, rhea, and kiwi.All share certain morphological similarities (such as a breastbone without a keel) not found in other birds, but they live on different continents.In the past, some ornithologists regarded their similarities as homoplasies, but they are now thought to be synapomorphies.Based on this information, you would conclude that the ratites were once regarded as a _______ group but are now believed to be _______.