The way to determine which of two fossils is older is

The way to determine the actual age of fossils is

A type of rock made of hardened sediment

A species that has no living members today is called

Fossils do not consist of bones, bone fragments, imprints, and preserved remains

How can scientists determine the relative age of a fossil

How can scientists determine the absolute age of a fossil

Organisms began living on Earth about 3.8 billion years ago.  Then 1.2 billion years ago, ______ evolved

Unicellular organisms are those organisms that are made up of a single cell

What were the first land-dwelling multicellular organisms ?

What were the first animals to live on land?

Periods during Earth’s history when huge numbers of species suddenly disappeared are called _____.

According to patterns in the fossil record, what typically happens after a mass extinction?

During the Cretaceous Extinction, about 65 million years ago, the fossil record for dinosaurs disappeared

Which era is the most modern and the one that we are currently living in?

The process through which species change and develop new traits over time is called ____.

Where did Darwin go to study the variations in different species of animals?

Darwin’s theory that members of a species who are best suited to their environment survive and reproduce at a higher rate than other members of the species is called ____.

The four key principles of Darwin’s theory of natural selection are overproduction, variation, adaptation, selection

Which of the four key principles of Darwin’s theory of natural selection explains why no two zebras have the exact same pattern of stripes?

Which of the four key principles of Darwin’s theory of natural selection explains why, out of several thousands of eggs that a pike lays, only several dozen will live to adulthood?

An inherited trait that gives an organism an advantage in its particular environment is called a(n) ____.

The principle behind selection is that only those species of organisms who have developed an adaptation that has been passed on from one generation to the next will survive the most.

What was the name of Darwin’s book in which he published his ideas about evolution and natural selection?

Finches on one of the Galapagos Islands have thin beaks for capturing insects.  Finches on another island have short, heavy beaks for pecking trees.  This is a result of ____.

When the cichlid population of Lake Tanganyika was separated into isolated groups, _____ occurred.

23)  A(n) _____ is a widely accepted statement based on scientific evidence that helps explain and predict natural phenomena.

23)  The three main types of evidence on which the theory of evolution has been built and has been accepted by the scientific community are fossil, biological, & genetic.

A(n) _____ is an early form of an organism from which the later forms descend?

Humans and chimpanzees cannot be traced back to a common ancestor because humans evolved from chimpanzees.

The ancestors of snakes used legs to walk on land.  The small leg bones that are still in the bodies of snakes are called ______ organs.

Genetic evidence is based on the study of _____ sequences.

In the image above, the structure labeled A in the figure below is an example of a(n) _____ organ for a whale.

  In the image above, the structures labeled B, C, and D in the figure below are the forelimbs of a human, whale, and bat, respectively.  They all have the same basic structure.  These are examples of ______ structures.

The forelimbs of the human, whale, and bat do not have the same function for each organism.

A species that is in danger of becoming extinct is called ____.

A species that is in trouble but is not quite endangered is called ____.

Once a species is classified as endangered, it is impossible for it to recover and be taken off the endangered list.

Humans, chickens, and rabbits look similar to each other in their earliest stages of life.