Question

Which forces acting on locomotion are most important for movement on land, in water, and in air? What adaptations in form provide for more efficient movement (function) through different media (e.g. air, water)

Answer 1

Fishes swim by making their body flexible and making their tail move back and forth. This is done by stretching and expanding their muscles on one side of the body, while relaxing the muscles on the other side. This motion helps them move forward through the water. Fishes use their back fin which is known as caudal fin to help them pushing through the water.

For terrestial animals like humans, the locomotion occurs through initiating muscle contraction in order to apply a force against another object, such as the floor or ground

For locomotion in air, birds have to achieve flight by overcoming the downward pull of gravitational forces by producing lift. There is an inherent asymmetry between the top and bottom surfaces of the wings of the birds, also called camber, This allows air flow velocity over the wing to be faster than below, which results in greater pressure application to the bottom surface. This difference in pressure causes a net upward force on the wing, thus allowing the bird to lift off the ground.