Because it's the female who decides who she will select as a partner. That means that it's the male birds that will have to impress her by their coloration, singing and other displays of health and fitness.
because1
In Birds of prey (raptors), the female is ALWAYS bigger on average. Usually by about a third.
Normally, yes male koalas are larger than female koalas.
Male cheetahs are generally larger than females.
No, females are larger in nearly all raptors.
males that are much larger than females
Male gorillas are larger. They grow 350-600 pounds. Females weigh 220 to 260 pounds.
Males are a bit larger than females.
which are larger male elephants or female elephant
the male hamster is larger, although the females can get large in size to. the females only will get bigger if they are fat.
Moas were peaceful giant birds. Females grew larger than males and recent discoveries suggest the males performed loud mating calls to attract females. The females would lay eggs that the male would fertilize.
Most male birds are brightly colored to attract females.