Evolution Unit Test 22

What is natural selection?

• inherited characteristic that increases chances of survival

• organisms with traits well suited to their environment survive and reproduce at a greater rate

• a growing population causes a scarcity of resources

• differences in the DNA sequence

Some organisms that share a common ancestor have features that have different functions, but similar structures.  These are known as

• vestigial structures
• analogous structures
• homologous structures
• fossil structures

Evolved from different ancestors, but due to living in similar environments have a similar function.

• Homologous structures

• Analogous structures

• Vestigial structures

• All of the above

According to this cladogram, sharks are MOST closely related to which organism? 

• Amphibians
• Ray finned fish
• Crocodiles
• Birds

An anatomical feature that no longer seems to have a purpose in the current form of an organism

• Homologous structure

• Analogous structure

• Vestigial structure

• None of the above

When the Grand Canyon in Arizona formed, two populations of one squirrel species were separated by the giant canyon. This is an example of _____________ speciation.

• Allopatric

• Sympatric

• Simple

• Divergent

A speciation in which new species evolve from a single ancestral species while inhabiting the SAME geographic region.

• Sympatric speciation

• Allopatric speciation

• Complex speciation

• Divergent speciation

A  population of cockroaches was sprayed with an insecticide.  Some cockroaches survived and produced a population of cockroaches that was resistant to this spray.  What can BEST be inferred from this example?

• species will adapt no matter what the environment
• environment has no effect on the survival of an organism
• Individuals with favorable variations survive and reproduce
• Insecticides cause mutations that are passed on to the next generation

How do you "win" at natural selection?

• survive

• go extinct

• survive & reproduce

A slight difference in an inherited trait between individual members of the same species.

• variations
• adapatations
• homologous structures
• analogous structures