Exam 16: The Evolution of Biodiversity

The appearance of eukaryotes may have been delayed until the Earth's atmosphere accumulated more _______________.

Which of the following is NOT an example of a fossil?

Which of the following has NOT been proposed as a possible cause of mass extinctions?

The first single-celled organisms arose 3.5 ____________________ years ago.

The following figure shows the number of living taxonomic families that existed on Earth during the last 540 million years.The sudden decreases in family numbers at 445,360,250,200,and 65 million years ago represent Earth's five mass extinction events.Based on these data,which mass extinction had the biggest impact on the overall diversity of life on Earth?

Which of the following represents the order in which terrestrial life appeared in the fossil record?

Dinosaurs lived on Pangaea.

Which of the following are unique to mammals and the most recent common ancestor of mammals but lacking in nonmammals?

Evolutionary novelties shared by an ancestor and its descendants but not seen in groups that are not direct descendants of that ancestor are known as ___________.

Which of the following methods would give the most accurate estimate of the age of a fossil?

You are looking at the side of a cliff with many clearly visible layers of rock.In the top layer,you find the fossil of a mouse.In the next layer down,you find the fossil of a frog.Two layers down from that,you find the fossil of a beetle and,in the deepest layer,the fossil of a millipede.This is evidence that _____________.

Many organisms decompose rapidly after death; some organisms have had soft bodies and some areas where organisms died have undergone massive geologic changes.For these reasons,the ____________________ record is incomplete.

Mass extinctions can often lead to adaptive radiation since they provide new ecological and evolutionary opportunities for groups of organisms that were previously important to only a minor degree.

The human and chimpanzee genomes are approximately 98% similar; thus,the 2% of genes that are different accounts for all of the differences between the two organisms.

The Cambrian explosion ___________.

For insects,could there be a connection between being the first organism to fly and being the most diverse terrestrial organism today?

The leg bones of the first tetrapod (shown in the following diagram)are hypothesized to have evolved from bones in the ____________.

The following organism is the evolutionary ancestor of the modern whale.

Fossil anklebones from the ancestors of whales and the anklebones of hippopotamuses have the same shape,which is an adaptation for running on land.This suggests that _____________.

The coelacanth and the lungfish are the two main candidates reputed to be a close relative of the ancestral fish that first used fins to walk on land and give rise to the ____________.