A new study says more than two million years ago, one-third of the world’s large marine animals, including large sharks, cats and turtles, disappeared in an extinction event. Some manatees and whale species, as well as the giant giant shark (Carcharocles megalodon), disappeared in this extinction event. Researchers analyzed a shark tooth fossil
Sina Technology News Beijing time 6 According to foreign media reports, a new study said that more than 200 million years ago, one-third of the Earth’s large marine animals – including large sharks, cetaceans and turtles, etc. – are in an extinction Incident, the researchers found that this previously unknown extinction event on the Earth’s biological diversity has brought a huge impact. The research team hopes the discovery will help prevent the same thing from happening today.
saber-toothed tiger, mammoth and other large terrestrial animals in the ice age extinction has long been known. Now, scientists from the University of Zurich, Switzerland and the Berlin Museum of Natural History have found that similar incidents have occurred in the oceans before these terrestrial animals are extinct.
The research team analyzed the fossils of the large fauna between the Pliocene and the Pleistocene (5.3 million years ago to about 9700 BC). “We found that about one-third of large marine animals disappeared from 3 million to 2 million years ago,” says Catalina Pimiento, head of research. “So the human understanding of the ocean The animal community has undergone great changes and diversity has declined significantly. “
This extinction event resulted in a 55% reduction in the diversity of marine mammals. Up to 43% of the turtle species, 35% of the seabirds and 9% of the shark species also disappeared. Although many species disappeared, but the new form of life in the next Pleistocene also continue to appear. About a quarter of the animal species, including polar bears, swallows, yellow eyes penguins, are present in this period.
The researchers are not sure what led to this extinction. “We found that the sea level change caused by glacier activity led to the disappearance of the coastal area, which may be the cause of the extinction event.”
The team analyzed the Pleistocene to the Pleistocene (Pleistocene) 530 million years ago to about 9700 BC) between large fauna fossils. Large marine marine thermostats such as manatees are particularly vulnerable in global environmental change. Despite the disappearance of many species, new forms of life, such as polar bears, are also emerging in the next Pleistocene. In order to understand the consequences of this extinction event, the researchers analyzed the shallow continental shelf area. They found that there were seven functional entities – animal groups with similar characteristics – disappeared in the Pliocene nearshore waters. This does not sound so serious, but the seven functional entities have led to a 17% reduction in the total diversity of ecological functions. In addition, 21% of the total diversity has also changed.
Previously predators have disappeared, new competitors appear, forcing marine animals to adjust their relationship with each other. The researchers also found that near-end habitat was significantly reduced due to drastic changes in sea level at extinction events. Large marine thermostats are particularly vulnerable in global environmental change. “Our model shows that thermostatic animals are particularly susceptible to extinction,” says Piena Anto. “For example, some of the manatee and whale species, as well as the giant giant shark (Carcharocles megalodon), are gone. The study shows that large marine animals are much more fragile than the ones we thought to be in the face of the global environmental changes in the recent geological age. “Dr. Piananto also pointed out that under the influence of mankind, Large marine animals are also very fragile. (Any day)