A female fly, full of fertilized eggs, is swept by high winds to an island far out to sea. She is the first fly to arrive on this island, and the only fly to arrive in this way. Thousands of years later, her numerous offspring occupy the island, but none of them resembles her. There are, instead, several species each of which eats only a certain type of food. None of the species can fly, for their flight wings are absent, and their balancing organs (i.e., halteres) are now used in courtship displays. The male members of each species bear modified halteres that are unique in appearance to their species. Females bear vestigial halteres. The ranges of all of the daughter species overlap.In each fly species, the entire body segment that gave rise to the original flight wings is missing. The mutation(s) that led to the flightless condition could have

TLS Online TPP Program

#Question id: 12112

#Unit 10. Ecological Principles

The presence of altruistic behaviour is most likely due to kin selection, a theory maintaining that

TLS Online TPP Program

#Question id: 12113

#Unit 10. Ecological Principles

In belding’s ground squirrels, it is mostly the females that behave altruistically by sounding alarm calls. What is the likely reason for this distinction?

TLS Online TPP Program

#Question id: 12114

#Unit 10. Ecological Principles

Researchers have found that a region of the canary forebrain shrinks during the nonbreeding season and enlarges when breeding season begins. This annual enlargement of brain tissue is probably associated with the annual

TLS Online TPP Program

#Question id: 12115

#Unit 10. Ecological Principles

Although many  chimpanzee populations  live  in  environments containing oil  palm  nuts,  members of  only  a  few populations use stones to crack open the nuts. The most likely explanation for this behavioural difference between populations is that

TLS Online TPP Program

#Question id: 12116

#Unit 10. Ecological Principles

Which of the following is not required for a behavioural trait to evolve by natural selection? 

TLS Online TPP Program

#Question id: 12117

#Unit 10. Ecological Principles

Female spotted sandpipers aggressively court males and, after mating, leave the clutch of young for the male to incubate. This sequence may be repeated several times with different males until no available males remain, forcing the female to incubate her last clutch. Which of the following terms best describes this behavior?