Study

The information below is about a scientific study of horses. 

A group of scientists are studying a population of horses. They have been collecting data on the characteristics of these horses for many generations. Horses are able to reproduce when they reach 18 months. Once mature, the female adult horse typically has one offspring each year. Occasionally a horse will have twins. Scientists are looking at the traits that are being passed down to the offspring each generation.     

Students are trying to find out if the scientific study above is involving natural selection or artificial selection. What questions should the students ask the scientists to determine which process is taking place in the above study? 

• Do the horses choose their mate or do the scientists choose their mate?

• What color horses are involved in the study and is one color dominant over another?

• Artificial selection and natural selection both result in changing traits in species over generations.

• Do the horses take care of their offspring or do the scientists take the offspring away?

Use the information and tables to answer the following question.

The tables show fossil evidence found in one area during three different time periods.

The environment during Time Period 1 was very hot and rainy. Over time, the environment became much drier.

What can you conclude from this information?

• Fossil A was better adapted to a dry environment because there is a large population of them in Time Period 1.

• Fossil B struggled to survive in a dry environment because there are none of Fossil B in Time Period 1.

• Fossil C survived best in a rainy environment because there is a large population of them in Time Period 3.

• Fossil C was best adapted for a dry environment because its population increased in Time Period 3.

Use the information and diagram to answer the following question.

Pakicetus is described as an early ancestor to modern whales. These organisms were land mammals, but fossil evidence shows a relation to whales and dolphins based on a number of specializations of the ear related to hearing underwater.

The diagram shows three different skulls in the whale fossil record.

Which additional claim can be BEST supported by the evidence from the skulls in the whale fossil record?

• The fossil record does not give enough evidence about the mammals to determine if there is a relationship between the three skulls.

• The fossil record shows similarities in the skulls of the mammals, which shows that they must have had similar habitats and environments.

• 
  The fossil record shows that some mammals evolved so that their nostrils are further at the top of their skull for better breathing while in the water.

• The fossil record shows differences in the skulls of the mammals, which shows that they are from three separate species that all lived at the same time.

Do these fossils support the theory of evolution?

• yes, because they suggest that the feet and teeth of the horselike animals adapted to changing environments and available food sources

  
  

• yes, because all of these horselike animals contain the simplest and most primitive type of cells, indicating that they are related

• no, because they do not show a pattern of change since these horselike animals all look distinctively different

  
  

• no, because all mammals have teeth, bones, hair, and the ability to move from place to place

  
  

The diagram below shows undisturbed sedimentary rock strata. In which layer will the most complex organisms be found?

• Layer A

• Layer B

• Layer C

• Layer D

The pictures show a fossil of a glyptodon and a live armadillo, two different species. Glyptodons existed between 2,500 and 10,000 years ago, while armadillos exist today.
What do the pictures suggest about the armadillo?

• The armadillo is distantly related to the glyptodon.

  
  

• The armadillo and glyptodon used to breed together years ago.

  
  

• The armadillo was a predator of the glyptodon in the past.

  
  

• The armadillo evolved from the glyptodon through artificial selection.

  
  

The diagram below shows the gradual change over time in the anatomy of the horse.
Which concept is best illustrated by the physical variations in the horse is body size and structure over time?

• artificial selection

  
  

• acquired characteristics

  
  

• evolution

• inheritance

The picture shows the fossils of three species of mosasaur, large marine reptiles that are now extinct.
What do the similarities in these mosasaur fossils indicate?

• that these mosasaurs all expressed similar behaviors

  
  

• that these mosasaurs evolved from a common ancestor

  
  

• that these mosasaurs were all genetically identical

  
  

• that these mosasaurs lived in different environments

  
  

Use the information and model to answer the following question.

Fossils found in Earth's sediment give us clues to Earth's past.

Based on the fossil record, what conclusions can be drawn about the changes in this area over millions of years?

• the continents were joined in one land mass

  
  

• the climate became colder

  
  

• the sea dried up

• the glaciers melted