Evolution

The scientific theory of evolution is supported by different types of evidence. The diagrams below show the skeletons of two different animal species. How does comparing the skeletons of these animals provide support for the scientific theory of evolution?

•  It provides information about the organisms' habitats.
•  It shows possible common ancestry between organisms.
• It provides information to determine the organisms' ages.
• It shows possible chromosomal similarities between organisms.

According to fossil records, the horses that lived 50 million years ago were much smaller, weaker and slower than modern horses. Which process is most likely responsible for the changes that have led to the increased size, strength, and speed in horses?

• commensalism
• inbreeding
• migration
• evolution by natural selection

The diagram illustrates an embryonic stage of two organisms.Which of the following can be determined by observing the embryos shown in the diagram? 

• The organisms share a common ancestry.
• The organisms belong to the same genus.
• The organisms are native to the same geographic areas.
• The organisms will grow into anatomically similar adults.

Scientists have found evidence that about 2.4 million years ago a gene regulating jaw muscles mutated and may have led to the more graceful human jaw we see today. The diagram below shows the skulls of 3 hominid species.Which statement below most closely explains the link between jaw size and hominid evolution? 

• The jaws of hominids evolved to be smaller and less protruding over time. 
• The jaws of hominids evolved to be smaller and less protruding over time. 
• There appears to be no change in the jaws of hominids over time.
• The jaws of hominids changed over time due to a change in brain size. 
  

Scientists are studying the evolutionary history of a group of plants in the United States, and they developed an evolutionary tree, as shown below.Which statement can be inferred from the evolutionary tree?

• Species 1 is most closely related to Species 8.
• Species 2 is most closely related to Species 3.
• Species 3 is most closely related to Species 7.
• Species 5 is most closely related to Species 6.

 The diagram represents the relationship between beak structure and food in several species of finches found on the Galapagos Islands. The different beak structures observed in the diagram are evidence of

•  different species of finches adapting to different environments over many generations
•  finches changing their beak characteristics so that they could feed efficiently
• finch species with different beak structures coming to the Galapagos Islands from the mainland
•  finches mating with birds of other species and acquiring some of their traits

Change over time...

• Evolution
• Nucleotide 

Charles Darwin came up with this theory 

• Natural Selection
• Mutation

To adjust to a changing environment

• Mutation
• Adapt

Darwin wrote that organisms with traits that are best suited to the environment will ________________

• increase in number
  
• become extinct