according to darwin, why do modern giraffes have long necks?
a
giraffes have always had long necks like the modern ones.

b
earlier short-necked giraffes stretched their necks over a long period of time.

c
ancient giraffes developed short necks and pass this trait to their offspring.

d
giraffes born with longer necks would survive better in an environment with tall tr

Which of the following factors would not contribute to allopatric speciation? a) a population becomes geographically isolated from the parent population. b) the separated population is small, and genetic drift occurs. c) the isolated population is exposed to different selection pressures than the ancestral population. d) different mutations begin to distinguish the gene pools of the separated populations. e) gene flow between the two populations is extensive.