Question

Hummingbird bill length data was collected and graphed in a particular environment. Based on the data collected, which is the BEST conclusion drawn? A) The environment is selecting against all longer bill length birds. B) Due to natural selection, a virus has killed off all medium bill length birds. C) The environment has a greater amount of long nectar tubed flowers and short nectar tubed flowers causing disruptive selection in medium bill length birds. D) The environment has a greater amount of long nectar tubed flowers and short nectar tubed flowers causing stabilizing selection in medium bill length birds.

Answer 1

C would most likely be the correct answer: think of Darwin's finches and their varying bill lengths. This is all due to what they can eat. The same would apply to the Hummingbirds in this diagram: there is an abundance of short and long tubed flowers, thus causing disruptive selection in the medium sized bills (as they wouldn't fit properly). 

Answer 2

C) The environment has a greater amount of long nectar tubed flowers and short nectar tubed flowers causing disruptive selection in medium bill length birds.

Took that same test :)