The fruit fly drosophila melanogaster has an allele that confers resistance to ddt and similar insecticides, laboratory strains of d. melanogaster have been established from flies collected in the wild in the 1930s (before the widespread use of insecticides) and the 1960s (after 20 years of ddt use) lab strains established in the 1930s have no alleles for ddt resistance. in lab strains established in the 1960s, the frequency of the ddt-resistance allele is 37%. which statement is correct?
a) resistance to ddt evolved in some fruit flies in order to allow them to survive
b) alloles for ddt resistance arose by mutation during the period of ddt use because of selection for pesticide resistance
c) the evolutionary fitness associated with the heritable trait of ddt resistance changed once ddt use became widespread

What two fields of study provide the core information that is used to classify organisms?

Some birds look for food near cattle and other livestock. the movement of the cattle churns up the ground, making insects available to the birds. the cattle appear to be unaffected by the presence of the birds. what kind of relationship exists between the birds and the cattle? o a. parasitism o b. commensalism o c. predation o d. mutualism

Can someone pretty me with this ? it’s urgent. compare the three theories of emotion. here are the three theories of emotion. cannon-bard theory of emotion: the belief that both psychological arousal and emotional experience are produced stimultaneously ( at the same time) by the same nerve stimulus. james-lange theory of emotion: the belief that emotional experience is a reaction to bodily events occurring as a result of an external situation. ( “ i feel sad because i am crying.) schachter-singer theory of emotion: the belief that emotions are jointly determined by a nonspecific kind of psychological (bodily function) arousal and its interpretation, based on environmental ( natural surroundings) cues. which of these theories makes most sense to you? why. your response should be written using proper english spelling and grammar. and it needs to be 10 complete sentences.