Question

what is evolution of long neck and forelimbs of giraffe ??​

Answer 1

The accepted theory on giraffe evolution is that the giraffes with the longest necks passed on their genes through natural selection, and that it took millions of years to get the animal we see now. The two forces that drove giraffes towards elongating their necks are simple. The need to eat and the need to breed.

Answer 2

• In short, giraffes' long necks are the result of generation upon generation of repeated stretching and inheritance.

• The English naturalist Charles Darwin also thought the giraffe's extraordinary legs and neck must have something to do with foraging. "The giraffe, by its lofty stature, much elongated neck, fore-legs, head and tongue, has its whole frame beautifully adapted for browsing on the higher branches of trees," he wrote in On the Origin of Species in 1859.

• But Darwin did not buy Lamarck's ideas on how evolutionary change came about. Instead he argued that the giraffe's neck results from repeated "natural selection". Long-necked giraffes were more likely to survive hard times than their short-necked rivals.

• The French zoologist Jean-Baptiste Lamarck is usually credited as the first person to suggest that long necks have evolved in giraffes because they allow them to get to the parts other herbivores cannot reach.

• As the giraffe lives "in places where the soil is nearly always arid and barren, it is obliged to browse on the leaves of trees and to make constant efforts to reach them," he wrote in his 1809 book Philosophie Zoologique. "From this habit long maintained in all its race, it has resulted that the animal's fore-legs have become longer than its hind legs, and that its neck is lengthened."