Exam 13: Adaptation and Species

Of the three species of sea urchins shown,one species is considered allopatric with Echinometra lucunter and the other is considered sympatric with E.lucunter.Name the allopatric species and identify one factor that may have led to speciation between E.lucunter and the allopatric species.Next,name the sympatric species and identify one factor that may have led to speciation between E.lucunter and the sympatric species.

A large population of animals is split in two by a physical barrier.Over time,the genetic makeup of the two resulting populations becomes more and more different until each population becomes a separate species.This is an example of

Sympatric speciation

Genetic adaptations in two closely related species living within the same territory indicates that

The two squirrel species shown in the figure below arose from the same ancestor.The Kaibab squirrel lives on the north rim of the Grand Canyon and the Abert's squirrel lives on the south rim.Which is the MOST likely explanation for their speciation?

Before the cultivation of the apple tree,apple maggot flies laid their eggs exclusively on the fruit of Hawthorne trees.As apple orchards became more prominent,apple maggot flies began to lay their eggs on both the fruit of the Hawthorne tree and the fruit of cultivated apple trees.Now,apple maggot flies that live on apple trees mate and lay their eggs at different times of the year than apple maggot flies that live on Hawthorne trees.Is this an example of reproductive isolation?

Which of the following is an example of a postzygotic barrier?

A lizard learns to avoid predatory birds after being attacked and losing part of its tail to a bird.What is required for this avoidance behavior to be considered an adaptive trait?

The rough-skinned newt produces one of the most potent toxins on the planet.Scientists in Oregon have found that as newts evolve to produce a more deadly toxin,their primary predator,the garter snake,evolves ways to resist the toxin.This is an example of

Two birds with distinct differences in their plumage successfully mate and produce viable,fertile offspring.Using the biological species concept,explain whether these two birds would be defined as a single species.Also address whether you would require more information to make this determination.

Convergent evolution involves unrelated,or distantly related,organisms developing similar traits.Coevolution is similar to convergent evolution in that coevolution also

The three sea urchin species shown below are separated by gametic isolation.Do these species fit the definition of species as defined by the biological species concept? Why or why not?

The best explanation of the role of coevolution in speciation is that coevolution

The faster a cheetah can run,the more likely it is to capture its prey.Cheetahs with longer legs are able to run faster than those with shorter legs.Although the existing cheetah population shows a variety of leg lengths,cheetah legs are not continuing to increase in length from one generation to the next.Which of the following is a possible explanation?

Although populations of North American apple maggot flies are not geographically isolated,they appear to be in the process of diverging into two new species.Which of the following could be causing speciation between two populations in the lack of geographic isolation?

When populations of a species are separated by a physical barrier,thereby becoming geographically isolated and subsequently reproductively isolated from one another,________ speciation can occur.

Which of the following organisms would best be identified as a species using the biological species concept?

Gene flow is completely blocked between two populations of a flowering plant for 300 years.One population develops light green leaves,tall spindly stems,and purple flowers.The other population develops dark green leaves,short stems,and white flowers.At the end of the 300 years,people begin planting these flowering plants together in decorative gardens.People quickly realize that these two flowering plants are capable of interbreeding.Did speciation occur during the 300-year separation? Explain your reasoning.

Bacteria reproduce asexually,so scientists classify them based on

For two populations to accumulate enough genetic differences to cause speciation,the factors that promote these differences