Biomimetics is an upcoming trend amongst aerodynamic designers, motivating several investigations into unusual aircraft body and wing shapes. These studies get their inspiration from shapes and mechanisms found in nature and try to improve the aerodynamic behavior of an aircraft.
For example, tubercles, small bumps found on the flipper of the humpback whale, help control the flow over a wing at high angles of attack.
Another passive flow control technique stemming from the biomimetics sector are the riblets. These small surface protrusions, aligned with the direction of flow, are inspired from the skin of the shark and are investigated for their drag reduction capabilities.
Wing fences and vortex generators, imitating bone structures of insects, bats and birds are also included in this category.
On the other hand, birds like the eagle have, for a long time, inspired aircraft design, while sea creatures like the manta ray incorporate innovative geometry designs like the Blended-Wing-Body shape.