24. History of Life on Earth

Prior to the Cambrian explosion, most animals were small and soft-bodied. What development appears to have spurred adaptations such as sharp spines, claws, and body armor (shells)?

What evidence most strongly suggests that an impact by an asteroid or meteorite may have caused the extinction of the dinosaurs?

Adaptive radiations are often seen after __________.

What were the two major "problems" that had to be solved before plants, animals, and fungi could fully move into terrestrial habitats?

Plants colonized land in the company of __________; their symbiotic relationships still exist today.

Which of the following best describes how the breakup of Pangaea affected evolution?

Lake Malawi, in the African Rift Valley, is home to more than a hundred species of cichlid fishes, each with slightly different diets and habits. All these species probably evolved from a common ancestor, making them an example of __________.

The fauna and flora of Australia are very different from those of the rest of the world. Why might this be true?

Although they originated around 180 million years ago, mammals underwent an adaptive radiation starting approximately 65 million years ago. Why?

Mutations in what class of genes have probably been responsible for many of the changes leading to the great diversity of life existing today?

If the feathers of extant flying birds originally arose as thermoregulatory devices in ancestral reptiles, then flight feathers could be accurately described as __________.

In the species selection model, __________ is to macroevolution as __________ is to microevolution.

Which of the listed examples is a current hypothesis regarding the Cambrian explosion?

Which of the following occurred during the Mesozoic era?