Earth History

What conclusion did scientists draw about the reptile?

• The skull evolved as the reptile developed stronger jaws.

• The reptile evolved from living in water to living on land.

• The reptiles were different ages when they died.

• The reptile was never properly preserved during fossil formation.

According to the geological time scale ____________________ evolved after the first insects evolved.

• mammals

• bacteria

• cells with a nucleus

• multicellular organisms

According to the fossil record, which of these evolved after amphibians? Select two options.

• mammals

• sponges

• fish

• bacteria

• reptiles

Absolute dating relies on _____________________ elements, which are unstable elements that release energy as they break down.

Which pair of elements can be used to determine the age of a fossil that is over one billion years old?

• lead, which is radioactive, and uranium, which is stable

• carbon, which is radioactive, and nitrogen, which is stable

• argon, which is radioactive, and lead, which is stable

• potassium, which is radioactive, and argon, which is stable

Compared to absolute dating, what is an advantage of relative dating?

• A single fossil can be dated by itself.

• The actual age of a fossil can be determined.

• Fossils do not need to be arranged in different layers of rock.

• There is no limit to the age range of the fossils being dated.

Which conclusion is best supported by the diagram?

• Trilobites and gastropods are the youngest fossils.

• Crinoids and gastropods have lived during the same time period.

• Ferns have existed for a longer period of time than coral.

• Every ammonite fossil is older than the gastropod fossils.

A scientist is using relative dating to determine the age of a fossil that she discovered.

What would allow her to draw the best conclusions about fossils that are younger than the one she discovered?

• measuring the amount of carbon and nitrogen in the surrounding rock

• measuring the amount of potassium and argon in the surrounding rock

• finding fossils in the same area that are in layers deeper under the surface

• finding fossils in the same area that are in layers closer to the surface

The diagram shows fossils buried in layers of sediment. Which statement is supported by the information in the diagram?

• The fossil in layer Z is the youngest.

• The fossils in layers Y and Z are younger than the fossil in layer V.

• The fossil in layer Y is older than the fossil in layer W.

• The fossil in layer X is older than the fossil in layer Z.

____________________ dating is the process of putting events or fossils in order from oldest to youngest without using actual dates.