Why might the different species of whales fail to recover even though hunting has been banned?

Question

A.  loss of genetic diversity
B.  loss of habitat
C.  introduction of invasive species
D.  increasing predation
E.  increased disease spread due to edge effects

Additional:
Clarify Question

· What is the key concept addressed by the question?
· What type of thinking is required?
      
 
Gather Content

· What do you already know about genetic diversity?
        

Choose Answer

· Given what you now know, what information and/or problem solving approach is most likely to produce the correct answer?
     
 
Reflect on Process

· Did your problem-solving process lead you to the correct answer? If not, where did the process break down or lead you astray? How can you revise your approach to produce a more desirable result?
        

Answer 1

A.  loss of genetic diversity

Additional:
Clarify Question

· What is the key concept addressed by the question?
        o This question addresses genetic diversity.
· What type of thinking is required?
        o This question is asking you to take what you already know and apply it to this unfamiliar situation.
 
Gather Content

· What do you already know about genetic diversity?
        o Several factors may synergize to threaten a species. In fact, a chain reaction is possible in which the action of one factor predisposes a species to be more severely affected by another factor.
        o For example, habitat destruction may lead to decreased birth rates and increased mortality rates. As a result, populations become smaller and more fragmented, making them more vulnerable to disasters such as floods or forest fires, which may eliminate populations. Also, as the habitat becomes more fragmented, populations become isolated, so that genetic interchange ceases and areas devastated by disasters are not recolonized. Finally, as populations become very small, inbreeding increases, and genetic variation is lost through genetic drift, further decreasing population fitness. Which factor acts as the final coup de grace may be irrelevant; many factors, and the interactions between them, may have contributed to a species’ eventual extinction.
 
Choose Answer

· Given what you now know, what information and/or problem solving approach is most likely to produce the correct answer?
        o After a population once falls to a low size, it may suffer lasting problems due to a lack of genetic diversity.
 
Reflect on Process

· Did your problem-solving process lead you to the correct answer? If not, where did the process break down or lead you astray? How can you revise your approach to produce a more desirable result?
        o The question required you to take what you already know and apply it to this unfamiliar situation.
        o Did you recognize that even if a threatened population recovers, it can suffer lasting effects from going through a genetic bottleneck?