Are birds better at flying than bats?

AYes. According to a study at Sweden’s Lund University, birds are more efficient fliers. This may be partly due to bats’ ears and leaf-noses (used in echolocation), which stick out and disrupt air flow. As a result, their bodies create less lift (the force keeping them off the ground) than those of birds. If the animal’s body generates a lot less lift than its flapping wings, airflow is affected, further reducing efficiency.

Birds and bats also differ in the way they flap. After beating their feathered wings downwards, birds bring them back up without creating significant aerodynamic forces. Bats flapping their membranous wings upwards, however, generate forward motion (thrust) and negative lift (a downwards force), which again affects efficiency.