Rock pocket mice are found in the deserts of the southwestern United States. They usually live on light-colored rocks and have light coats, with some having dark coats. About 1.7 million years ago, a series of volcanic eruptions left black lava deposits in regions where the rock pocket mice lived. The table shows frequency of allele distribution for dark and light coat color in regions with and without lava deposits. Based on the information provided, which traits in this population were most likely to be selected for, resulting in an increase due to natural selection?

A Stunning Adaptation

Pistol shrimp are a group of small crustaceans with one claw that is much larger than the other. When pistol shrimp snap the larger claw shut, a sharp cracking sound is produced. A pistol shrimp can use this sound to stun its prey, such as small fish. Some pistol shrimp even have pockets of tissue that cover their eyes for protection from the sound waves. The drawing shows an example of one species of pistol shrimp.

Scientists investigating this noise production have determined that it is not the snapping together of the two sides of the claw that results in the loud sound. The process is far more complex. As the two sides of the claw snap shut, a jet of water comes from the claw at a speed of up to 62 miles per hour. The moving water forms a low-pressure bubble behind it. As the pressure around the moving water stabilizes, the bubble pops, resulting in a loud bang.

Some pistol shrimp within a population do not have eye tissue pockets. What role will natural selection most likely have in the frequency of alleles responsible for the presence of tissue pockets in the shrimp population over time?

Which statement is not part of the concept of natural selection?

The diagram below illustrates the change that occurred in the physical appearance of a rabbit population over a 10-year period.

Which condition would explain this change over time?

A population of squirrels was separated during the formation of the Grand Canyon. Over time the squirrels, separated by the canyon walls and the Colorado River, became unique species. Which mechanism most likely caused the development of the new species?

Which statement best describes how geographic isolation can contribute to land animal speciation?

In order for new species to develop,

there must be a change in the

A mutation occurred in a population of red insects that produced brown-colored insects. Predators were able to see and catch red insects much easier than brown ones. What would be the most likely effect of this mutation on the frequencies of the red and brown insects in the population?

Which condition would most likely result in an increase in the phenotypic variation within a population?

The graph represents changes in an autosomal trait of a mouse population over time. Which statement best describes the occurrence at time 1?

A researcher observes two species of frogs in the same area. Both species have a similar diet. One species breeds in fast-moving streams, while the other species breeds in ponds. Both species are similar in appearance and have very similar DNA. Which information provides the best evidence that these two species descended from a common ancestor?

Many scientists have concluded that whales and dolphins have a more recent, common ancestor than do whales and sharks. Which characteristic most likely allowed scientists to make this conclusion?

The pitcher plant and venus fly trap plant have leaves that are modified to catch insects. In cacti plants, the leaves are shaped like spines. Leaves on each of these plants are homologous structures. What type of evidence does the presence of homologous structures provide?

A scientist studies birds on a set of islands. Based on their varied beak types but similar body structure, the scientist proposes that the birds had a common ancestral population, which then adapted to the local food sources of the different islands. Which best describes the scientist’s proposal?