The article discusses the peculiar features of the hingemouth fish, focusing on its unconventional mouth that baffled researchers for years. Evolutionary biologist L. Patricia Hernandez and her team spent five years studying the hingemouth’s unique feeding apparatus, which they named the proboscis. This structure is unlike any other fish’s mouth, with an opening inside the face and a second mouth at the tip of the proboscis. The hingemouth uses its trunk-like mouth to feed on detritus in the swampy forest pools of central west Africa, defying traditional logic for fish jaw modifications.
According to the article, the hingemouth’s ability to breathe air from the water’s surface and its flexible, cartilaginous jaws make it well-adapted to its challenging habitat. The researchers also discovered new anatomical structures and muscular arrangements in the hingemouth’s mouth through dissections and CT scans of museum specimens. Despite the challenges of training live hingemouths to eat on cue, the team successfully captured feeding behavior on video.
The researchers observed that the hingemouth can extend its jaws past 30 percent of its head length, a capability comparable to other fish species. However, they speculate that the extreme anatomical reorganization of the hingemouth’s face for feeding on detritus may limit its evolutionary potential. Nonetheless, they admire the hingemouth’s ability to adapt and survive in its environment, showcasing the diversity and extremes that evolution can produce.
