Mention of dolphins, it is a warm picture of human good friends and cute little residents of the ocean. But the news that misses a scientific community the most has broken such a cute fantasy and made people shout "dolphin is not guaranteed"!
On the Science News website of Science Outlook in the United States, news about the dolphin investigation was published. Not only is the dolphin's appearance ugly "angle of death", but the results of the study are surprising: dolphins can eat highly venomous sea snakes!
The dolphin's discovery of eating a highly venomous sea snake was due to the U.S. Navy strapped a camera to the dolphin. Dolphin research and the U.S. Navy, these two incompatible things can actually be put together?
It turned out that the U.S. Navy had strapped cameras to dolphins so that trained dolphins could help identify submarine mines and protect some of America's nuclear stockpiles, and then give the dolphins the freedom to feed in San Diego Bay.
Dolphins, which are quite kind and cute creatures in the public impression, are still not well understood by humans. Some basic things are not even clear, such as how dolphins specifically eat. Unexpectedly, however, when the dolphins foraged, they targeted the highly venomous yellow-bellied sea snake, which surprised the researchers.
The cameras, strapped to six Tursiops truncatus of the National Marine Mammal Foundation (NMMF), record footage and audio for six months — providing us with new discoveries about these mammals' hunting strategies and communications.
It's hard to imagine a dolphin eating 8 highly venomous yellow-bellied sea snakes (Hydrophis platurus). Although dolphins have previously been caught fighting with snakes, including puffer fish and playing with a large python, the video confirms for the first time that they may also eat these reptiles.
"Our dolphins show no signs of disease after eating the baby snake," the researchers wrote, but they acknowledged that this may also be unusual behavior because the dolphins are captive animals.
"Perhaps the dolphins' lack of experience eating with dolphin herds in the wild has led to the depletion of this outlier."
In addition to spotting dolphins eating highly venomous sea snakes, the camera also recorded dolphins catching more than 200 different species of fish, including sea bass, yellow croaker, halibut, courgette and tube fish.
Although these targeted fish tried to throw themselves out of the water to escape the dolphin's "claws", they were still eaten by the dolphin and fell into their stomachs. The researchers explain that dolphins are able to use sight and sound to catch prey. If at a distance, dolphins use echo positioning to catch prey. At close range, both visual and echo positioning are used.
The camera also revealed that instead of knocking the prey down, the dolphins used suction to swallow those prey that were still struggling.
Dolphins can be seen to have fairly strong throat muscles. Dolphins mostly suck fish from both sides of their open mouths, with enlarged throat muscles and sticking out tongues. The enlarged space in the inner mouth helps to generate negative pressure, which is increased by their sucking muscles.
This stormy painting style instantly shattered many people's impression of the gentle and cute dolphin. In the end, I knew the truth and I shed tears, or those who had filters endured all this!
Alas, what about the cute dolphins?