DNA Sequences Are the Most Frequently Used Character for Phylogenetic

question 6

Multiple Choice

DNA sequences are the most frequently used character for phylogenetic construction today, but DNA may not always be available. For which of the following would a phylogeny have to be constructed with nonmolecular methods for collecting character data?

• A) Ebola isolates from strains collected in Guinea, Sierra Leone, and Mali by Hoenen and his colleagues in 2014
• B) data collected by Killian and his colleagues to create a phylogeny of mammals that supports the Theria hypothesis
• C) fossils of Tiktaalik roseae discovered by Daeschler and his colleagues
• D) HIV isolates from the 1999 Benghazi Hospital AIDS outbreak

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Definitions:

External Validity

The degree to which the outcomes of research can be applied to different contexts and populations beyond the experimental environment.

Reversal Design

A single-subject experimental design in which behavior is measured to provide a baseline (A), then again after the treatment has been applied (B), then again after the conditions during baseline have been reintroduced (A), and then once again after the treatment is reintroduced (B). Also known as ABAB design.

Single-Subject Experiments

Research studies that focus on the response of a single subject to experimental treatments over time, allowing detailed observation of behavior changes.

Control Group

In experimental research, a group of subjects that does not receive the experimental treatment, used for comparison with the treated group.