Why don't animals have wheels? Answer as briefly as possible.
user
Several organisms are capable of rolling locomotion. However, true wheels and propellers—despite their utility in human vehicles—do not seem to play a significant role in the movement of living things. First, there are several developmental and evolutionary obstacles to the advent of a wheel by natural selection. Secondly, wheels are often at a competitive disadvantage when compared with other means of propulsion.
assistant
For the organisms that are capable of rolling locomotion, how do they move that way without wheels?
user
Some organisms use rolling as a means of locomotion. These examples do not constitute the use of a wheel, as the organism rotates as a whole, rather than employing separate parts which rotate independently
assistant