Earth's History and Geologic time

In the geologic history of the Earth, which time is characterized by the dominance of reptiles and the presence of small mammals, birds, and flowering plants?

• Cenozoic

• Mesozoic

• Paleozoic

• Precambrian

Which unit of geologic time represents the longest amount of time?

• Epoch

• Era

• Period

• Year

The end of each geologic era is marked by a significant event in geologic history. In general, what kind of event marks the end of the Paleozoic and Mesozoic Eras?

• mass extinction

• mass migration

• mountain formation

• volcanic eruption

What represents the geologic time of present-day Earth?

• Pliocene era, Jurassic period, and Cenozoic epoch

• Pliocene epoch, Paleozoic period, and Quaternary era

• Holocene period, Mesozoic era, and Cretaceous epoch

• Cenozoic era, Quaternary period, and Holocene epoch

A mass extinction occurred at the end of each era. Which extinction marked the end of the Mesozoic era?

• amphibians

• dinosaurs

• marine invertebrates

• woolly mammoths

What evidence would a scientist use to determine the age of rock in a layer?

• index fossils

• living fossils

• resin fossils

• trace fossils

What is the most logical conclusion about a layer of rock near the top of a canyon?

• The layers near the top are older than layers below.

• The layers near the top are younger than layers below.

• The top layer will have more fossils than layers below

• The top layer will have less fossils than layers below.

Which statement can be bestsupported by the fossil record?

• Most of the organisms on Earth have not changed over time.

• Most life forms that existed on Earth are now extinct.

• Humans and dinosaurs have existed on Earth at the same time.

• Human have lived on Earth for most of geologic history.

Dinosaur fossils are found in rock layers that are below the rock layers containing saber tooth tiger fossils. What can be inferred from this?

• Dinosaurs have evolved into saber tooth tigers.

• Dinosaurs preyed on saber tooth tigers.

• The dinosaur population was larger than the saber tooth tiger population.

• Dinosaurs and saber tooth tigers lived in different geological eras.

Geologists find a 40,000 year-old cave bear fossil. Which method should the geologists use to find the exact age of the fossil?

• radioactive dating

• recrystallization

• relative dating

• superposition