Ummm

[Bladvak]

How come birds can fly but we can't!

please keep the answer simple- im not that smart

 

[Rev. Green]

It gets more difficult to fly as the animal/bird gets larger.

If one bird is twice the length of another (but the same shape) its wings will be four times the size because they will be twice as long and twice as wide (2 x 2 = 4), but it will be eight times as heavy because it will be twice as high, twice as wide, and twice as long (2 x 2 x 2 = 8)

The extra lift from the wings is not enough to carry the extra weight. So men and very large birds can't fly.