Exam 23: Evolutionary Patterns: Phylogeny and Fossils

Streamlined bodies are common in many aquatic organisms: Dolphins, tuna, penguins, and sharks are all organisms that have streamlined bodies that reduce friction and drag. Body shape in each of these organisms would be considered an:

In order to be useful for constructing a phylogeny, a character must:

When selecting among multiple possible phylogenetic trees that fit our data, we commonly use the principle of _____, which means we choose the _____ possible hypothesis. In phylogenetic analysis, that means selecting the tree that represents the _____ evolutionary changes or mutations.

Traits that are shared by more than one member of a group because of common ancestry are known as:

Of the following taxonomic categories, which is the MOST inclusive?

With the advent of tools to incorporate molecular data, phylogenetic analysis can be used to:

A taxon that does NOT include the last common ancestor of all its members is a _____ group.

Examine the following table of characters in four different species of flower. Species A Species B Species C Species D Presence of sepals yes yes yes no Number of petals five five ten ten Arrangement of petals whorled whorled whorled whorled Number of carpels ten ten ten five Which character would be MOST useful for identifying the sister group of species D?

While taking a hike in the forest, you find some fossils in layers of sedimentary rocks whose age, you later find out, is said to cover a span of 100-400 million years. You decide to send the fossils out for analysis to a company that dates rocks by radioactive decay, and, some weeks later, receive a report informing you that a volcanic ash bed associated with one of the fossils has a 1:1 ratio of ²³⁵U: ²⁰⁷Pb. Do these data support or refute the assumed age of the rocks in which the fossil was found? (Note: The half-life of ²³⁵U is about 704 million years.)

The diagram below depicts three phylogenetic trees. Which of the three show the same sister group relationships among groups A, B, and C?

Phylogenetic trees can be built using:

Dinosaurs disappeared at the end of which period?

How can fossils provide evidence for macroevolutionary processes, such as the divergence of two species from a common ancestor?

Imagine that a taxonomist is provided with several flashcards on which the names of different species are written. She would likely organize these flashcards to construct a phylogenetic tree. To do this, would she pay attention to which species belong to which genus or class?

Individual populations cannot be included as separate taxa in a phylogenetic tree.

When several possible phylogenetic trees can be produced from a data set, the MOST parsimonious tree is the one that shows the:

Paleontologists did not just stumble across Tiktaalik, they formed a hypothesis about where they would find a transitional form between fish and tetrapods. What might have been the logical first step in deciding where to "look" for a transitional form between fish and tetrapods?

Which of the following would be considered characters?

Why is the fossil record NOT a complete catalog of biological history?

Examine Figure 23.2 below. What is the sister group to mammals?