A team of scientists used new technology to study the muscular and skeletal structure required for the mammals to take flight.
Brown University biologist Nicolai Konow and his team used a technology developed at the university called X-ray Reconstruction of Moving Morphology, or XROMM.
This technique combines 3D models of bones, created with either CT scans, MRI or laser scans, with X-ray videos to create 3D visualizations of moving skeletons.
The researchers also used another method called fluoromicrometry, which chemically labeled markers are injected into the animal’s muscles. These let the researchers directly measure changes in the length of the muscles during contraction and expansion as part of flight.
The findings indicate that the action of muscles powering animal movements through fluids may be influenced by series elasticity, and that at least some limb tendons in small mammals can be stretched by muscular and aerodynamic forces, enabling force control of joint movement. This is contrary to previous beliefs that small mammals like bats have tendons too stiff and thick to be stretched at all.
Dr Nicolai Konow (Brown University, USA), who led the research said: “Energy is stored in the triceps tendon, which is used to power elbow extension — in essence, elbow extension happens using “recycled” energy. State of knowledge, and our results, indicates that bats are unique among small mammals in stretching their tendons, as small mammal limb tendons are thought to be too thick and stiff to be stretched. By combining information about skeletal movement with information about muscle mechanics, we found that the biceps and triceps tendons of small fruitbats are stretched and store energy as the bat launches from the ground and flies vertically.”
This research will likely have relevance for the development of autonomous micro aircrafts and potentially also amphibious search and rescue vehicles.
X-ray Reveals Bat in flight
X ray video reveals bat flight trick.
Bat Takeoff Slow-Motion
This video shows high-speed light video of the take off and climbing flight behaviors of the Seba’s short tailed fruitbat.