A whale shark feeding at the water’s surface
Reinhard Dirscherl/Alamy
Whale sharks are the world’s largest living fish, measuring up to 18 metres long, but somehow they can suspend themselves in an upright position despite having a body density that’s greater than that of seawater. A study of captive whale sharks suggests this may be due to air they take in as they feed at the water’s surface.
Scientists have previously observed whale sharks (Rhincodon typus) feeding vertically in the wild. Although they often use slow fin movements to hold themselves in place while feeding on plankton …
source: newscientist.com