The History of Life on Earth

Front

The Age of Mammals refers to the ___

Back

Cenozoic Era

Front

During ___, life is thought to have originated from nonliving matter.

Back

Precambrian Time

Front

If the half-life of an unstable element is 5,000 years, what percentage of the parent material will be left after 10,000 years?

Back

25%

Front

Explain how primates and hominids differ.

Back

Hominids are a type of primate, but not all primates are hominids.

Front

In which era are we currently living?

Back

Cenozoic era

Front

What is the geological time scale?

Back

A system of chronological dating that relates geological strata to time.

Front

Define Precambrian Time.

Back

The earliest part of Earth's history, covering about 88% of its geological time.

Front

What major event marks the beginning of the Paleozoic Era?

Back

The Cambrian Explosion, which saw a rapid diversification of life.

Front

What are the main characteristics of the Mesozoic Era?

Back

It is known as the Age of Reptiles, characterized by the dominance of dinosaurs.

Front

What is a half-life in radioactive decay?

Back

The time required for half of the radioactive atoms in a sample to decay.