Changes in Population Over Time

What is mass extinction?

When a large number of species suddenly disappear as cause of a natural disaster or other catastrophic event.

What do terms variation, overproduction, and adaptation have in common?

They are all related to natural selection

What is variation?

Random mutations that are the source of new traits.

What is an example of variation?

The longer neck of a giraffe

What is overproduction?

When a species reproduces more offspring than can survive.

What is an example of overproduction?

Fish eggs

What is adaptation?

An inherited trait that increases the chance of survival and reproduction. They become more common in future generations.

What is an example of an adaptation?

Birds’s sharp beaks that they eat with or an animal’s camouflaged fur to blend in.

What is the correct order in which animals first appeared on land between insects, mammals, and reptiles?

Insects, reptiles, and then mammals

What is isolation?

When species are prevented from reproducing with their own species and new species are formed

What is a vestigial organ?

An organ that was once used and is no longer being used that may get smaller or disappear completely.

What animals were the first to live on land?

Insects

How do we determine the relative age of fossils?

Comparing it to other fossils and the rock layers it is found in.

What did Lamarck believe fossils showed us about species?

That they evolved over time.

What is natural selection, and what examples support this?

Organisms most likely to survive and reproduce based on variation, overproduction, selection, and adaptation.

What did Lamarck propose allowed species to evolve?

That acquired traits can be passed on to offspring.

What is evolutionary fitness?

An organism can survive long enough to reproduce and pass on its traits.

How can I tell if species have a common ancestor?

If two species have similar structures.

What is Carrying Capacity?

The maximum number of organisms an area can support

If a species has a low genetic diversity, what does it increase the risk of?

Extinction