Fossils 2019

The age of the Earth is estimated to be-

• 4.6 billion years

• 20 million years

• 12,000 years

• 1.2 billion years

This record indicates that-

• horse evolution occurred within the last 2 million years

• ancestors of modern horses had more than one toe

• there is no evidence of changes in structures in the evolutionary history of horses

• the evolution of horses leg structure occurred very quickly

What is the best definition for the half-life of an element?

• The time it takes for half of the atoms of a radioactive substance to break down

• The weight of a radioactive substance once half of its atoms have broken down

• The volume of a radioactive substance that remains when half of its atoms have broken down

• The number of radioactive atoms that remain after half of the atoms have broken down

A scientist discovers undisturbed layers of sedimentary rock. The upper most layers contain fossils of horseshoe crabs while the lower layers contain fossils of trilobites. Trilobites are now extinct, and are smaller, aquatic arthropods that have similar structures to modern day horseshoe crabs. This evidence most likely suggests-

• horseshoe crabs may have evolved from trilobites

• trilobites may have evolved from horseshoe crabs

• horseshoe crabs and trilobites are unrelated to each other

• horseshoe crabs are likely to become extinct

In the graph shown, what is the half life of the element?

• 4,500 million years

• 4,000 million years

• 5,000 million years

• 8,000 million years

What is the half-life of the element shown in the graph?

• 713 million years

• 1,218 million years

• 556 million years

• 50 million years

A student believes that frogs and toads evolved from the same species. What should the student review to investigate this hypothesis?

• The fossil record

• The diet of a toad

• The digestion of a frog

• The current living condition of frogs and toads

• The color variation between frogs and toads

Identify each situation in which a person used absolute dating to find the age of a fossil

• A man sent a bone to a science lab to find the remaining number of carbon 14 atoms

• A scientist compared the results of a test with a chart labed Radioactive Decay of Potassium 40

• A woman wanted to know if the seashell she discovered was older than her friend's seashell

• A teacher finds a paw print in a rock and decided it is older than other fossils she has found based on their location

The diagram represents the distribution of fossils in undisturbed layers of rock. Which of the following statements would be the best inference that can be made from this evidence?

• The fossils in layer C are older than layers B and A

• The fossils in layer A are older than layers B and C

• The fossils in layer B are older than C but newer than A

• The fossils in layer A are older than layer C

According to the graph, how long would it take for the element to go through two half lives?

• 1,356 million years

• 1,018 million years

• 713 million years

• 25 million years