Energy, the absence of molecular oxygen, chemical building blocks, and time were the requirements for (a) chemical evolution (b) biological evolution (c) the Cambrian radiation (d) the mass extinction episode at the end of the Cretaceous period (e) directed evolution

Scientists collectively call humans and their immediate ancestors (a) mammals (b) primates (c) anthropoids (d) hominoids (e) hominins

According to Scottish geologist Charles Lyell, the Cenozoic Era (including the Eocene, Miocene, and Pliocene epochs) extended over which of the following time periods in the fossil record? the Paleozoic Era, from the start of the Cambrian into the Permian Period the “age of reptiles”, from 252 million years ago to 66 million years ago the “age of birds and mammals”, from 66 million years ago to the present day the “age of fishes”, from 541 million years ago to 252 million years ago the Mesozoic Era, from the start of the Triassic into the Cretaceous Period

Scientists are examining the possible role of a large asteroid in the cretaceous mass extinction event. A large asteroid strike would likely have caused rapid climate cooling and the diffusion of sunlight. which of the following statements are the best null and alternative hypotheses when scientists look at the geologic evidence of extinction related to the asteroid strike?

Identify each of the following as an example of MICROEVOLUTION or MACROEVOLUTION.Then，state whether it supports the theory of gradualism or punctured equilibrium.（a） The Cambrian explosion（a period of rapid evolutionary change where many complex organisms evolved）.（b）The evolutionary change of animals and terrestrial plants.（c）beetles with a GREEN sheen are more prevalent than beetles with a BLACK sheen.

Archaic humans appeared as early as ___________ years ago. (a) 5 million (b) 1.2 million (c) 250,000 (d) 100,000 (e) 5000

There have been five main mass extinctions. Match each mass extinction event to its description. 1. Permian extinction 2. Cretaceous-Tertiary extinction 3. Triassic extinction 4. Devonian extinction 5. Ordovician extinction   a. This extinction was most likely due to a change in sea level. During this event, about 60% of all marine species were eliminated. b. This is the best-known mass extinction. It eliminated most large animals, including the dinosaurs. c. This was the most severe extinction event. About 96% of life on Earth died during this event. d. This extinction was most likely caused by climate change. About 80% of land animals died during this event. e. This extinction was most likely due to a change in sea level. It especially affected coral reefs.

拳 1 2 3 4 77811 Geologists searching for clues to the ancestors of modern-day vertebrate land animals should look in layer beds. of the fossil A) 1 B) 3. D) 4

Which of the following shows the correct sequence of periods in the Mesozoic era: a) Triassic, Jurassic, Cretaceous b) Cretaceous, Jurassic, Triassic c) Jurassic, Cretaceous, Triassic d) Triassic, Cretaceous, Jurassic

Evidence exists that a catastrophic collision between Earth and a large extraterrestrial body occurred 66 mya, resulting in the extinction of (a) worms, mollusks, and soft-bodied arthropods (b) jawless ostracoderms and jawed placoderms (c) dinosaurs, pterosaurs, and many gymnosperm species(d) mastodons, saber-toothed cats, and giant ground sloths (e) ferns, horsetails, and club mosses