Exam 25: Origin of Species and Macroevolution

A species of trilobite was found in the fossil record. At its first appearance, it is similar to an ancestor species but differs from the ancestor in several key characteristics. It seems to change little over several million years, then is extinct. This illustrates the concept of

The figure above is an example of

A frog and a toad mate. The frog drops it's sperm onto the toad's eggs as they are being laid, no offspring develop because the sperm cannot fertilize egg. This is an example of

A liger is a result from a male lion and a female tiger. Male ligers are usually sterile. This is an example of

The Mexican axolotl (Ambystoma mexicanum) is an amphibian that has a derived mode of development characterized by metamorphic failure. This mode of development results in an entirely aquatic life cycle in which the animal never develops a terrestrial phase. This is an example of paedomorphosis.

The Pax6 gene is considered a master gene because

Species are identified based on a unique combination of physical or molecular characteristics under the

The North American maggot fly diverged into two species because some individuals fed on apples rather than hawthorn trees. Apple fruit mature more quickly than hawthorn fruit, therefore maggot flies that fed on apples also developed more quickly. Pea aphids can feed on alfalfa or red clover; some aphids have higher fitness when eating clover others when eating alfalfa. Host preference can eventually lead to speciation because

If goats are crossed with sheep, embryos will form but cease development and spontaneously abort. This is an example of

A storm blows a small group of migrating birds off course and they land on an island too far from the mainland for them to fly back on course. The birds remain on the island for 100 generations when a second storm blows more birds from the mainland to the island. The new birds cannot mate with the established birds, even though they are originally from the same population. What has occurred to bring about this specialtion?

Which of the following genes is correctly matched with its function?

Podos measured beak depth and correlated this with finches songs. Using the figure above, which species of finch had the largest beak depth value and a vocal constraint between 2 and 3?

The Northern leopard frog (Rana pipiens) and Southern leopard frog (Rana utricularia) are morphologically similar, but they do not mate. They sound very different when calling for a mate. Which mechanism may explain why these frogs are listed as separate species?

Paedomorphosis is

Look at the chromosomes above and determine how many group(s) of Hox genes are associated with body types for each type of animal. These associations are based on anterior, group 3, central and posterior body development.