Why can't bats fly directly from the ground?

Bats cannot fly directly from the ground primarily because they need to fall to gain the necessary lift and momentum for their wings to function effectively. Unlike birds, which can launch directly from a stationary position due to their wing size and structural adaptations, bats have relatively short and broad wings that are not built for strong thrust from a standstill. By dropping a short distance, bats can catch the air beneath their wings and use gravity to help initiate flight. This mechanism is crucial for bats as it allows them to reach the speed needed to generate lift effectively.

The other options do not accurately represent the physiological and mechanical challenges bats face. For instance, bats are equipped with wings that, while short compared to their body size, are sufficient for flight once they achieve the right momentum. They also would not benefit from practicing on the ground as their natural behaviors and adaptations align to support flight more efficiently from a drop-off mechanism, rather than needing extensive space or additional practice.