Discovered Australian and New Guinea sharks evolved more legs, can hunt in shallow water

Where do humans come from? The theory of evolution says that their ancestor was an arboreal ape . Where do apes come from? Its ancestor was a mammal that appeared after the extinction of the dinosaurs. Where do mammals come from? It was the evolution of early marine fishes that climbed ashore.

So you probably also know that all life on land today originates in the ocean. Of course, there are some species that later found it difficult to live on land and decided to evolve to return to the ocean, such as dolphins, whales.

This study was carried out by Conservation International, the Scientific and Industrial Research Organization, the Florida Museum of Natural History in collaboration with the Indonesian Institute of Science and the Indonesian Ministry of Fisheries. These are sharks that pose no threat to humans. They are also known as 'bamboo sharks', which specialize in hunting small fish and invertebrates in shallow water. Swimmers can spot them briefly on the reefs at low tide.

So, at the present time, are there any fish that are evolving to move their habitat from the ocean to the shore? Recently, an international team of scientists from the University of Queensland in Australia, the United States, Indonesia and other countries conducted a 12-year study and found that several species of shark near Australia and New Guinea have actually evolved to gradually adapt to terrestrial habitats. And they're in the process of evolving to adapt to the low tide.

They are thought to have branched off from their ancestors 9 million years ago. The newest species may have evolved to walk on the seafloor about 2 million years ago. This makes them the most recently evolved shark species. It also gives people a completely new look at the evolutionary history of sharks. The sharks use their fins to walk, which also allows them to forage under rocks and corals. They have an average length of about 100 cm, mainly living in shallow coral reefs. The food of this species is small fish and sea grass.

Sharks are primitive and ancient species, possibly because living in the ocean is too comfortable, so according to the fossils found, we know that more than 1,200 sharks have appeared in 400 million years. In fact, almost all shark species have not evolved much, and many of them are considered living fossils.

However, this study by scientists surprised to find that there are 9 species of epaulette sharks in coastal waters near northern Australia and New Guinea. When the tide goes out, they use their pectoral and ventral fins to "walk" in shallow water and search for prey such as crabs, shrimp and small fish in coral reefs, which are gradually becoming top predators. in shallow reefs at low tide.

At first glance, people often picture them as geckos taking a walk, rather than a fish of the shark species that is famous for being fierce in the ocean.

Christine Dudgeon, a scientist from the University of Queensland, Australia, said: 'This species' ability to tolerate low-oxygen environments and walk on fins gives it a distinct advantage over small crustaceans and small crustaceans. molluscs'. The team hopes, through this research project, will help people understand why some animals change and adapt over time, while others stay the same. However, at present, the development of walking sharks is threatened by habitat destruction and overfishing.

The researchers believe that the reason why these sharks are able to walk on their fins in low-oxygen environments may be because they were in a separate area millions of years ago and evolved into a new species. Another reason could be that due to ocean changes, including sea level rise and fall, ocean currents and temperature changes, epaulette sharks must quickly adapt to this dynamic environment. . They have thus developed "the ability to defy the sky" , becoming a nightmare for small crustaceans and mollusks.

This shark is relatively small, with an average length of one meter.

Of course, we humans need not panic as soon as we hear that sharks have evolved to come ashore, because these sharks are relatively small, they average a meter in length, and pose no threat to humans. People. On the contrary, if their meat is delicious, then they will easily be turned into specialties by humans and if unlucky, human influences can easily make them extinct before they can evolve to be suitable. completely adapted to life on land.

Or not, even if their meat is not delicious, sooner or later humans will "invite" them to zoos and laboratories. So far, humanity has evolved, and no species poses a threat to us, except ourselves.