Manchurian crocodile, a colonial name derived from the Japanese in the 1940s, after 1931, japan occupied northeast China, including the then Rehe province. In 1940, the Japanese Ya Changke found two reptile fossils in the Lingyuan Niuyingzi Jiufotang formation in the core area of the Rehe biota. It was studied as the wedge-toothed Manchurian crocodile. This reptile is a semi-aquatic animal that feeds on small fish, amphibians and invertebrates. This fossil is found in many local areas. This is an ancient aquatic reptile, but not a true crocodile, but an extinct Bipocmic reptile of the Mesozoic Era.
However, the discovery and naming of such fossils by the Japanese is not unusual, and it is strange that the new discovery of this fossil more than sixty years later reveals the earliest life record of the same kind of voracious behavior.
In April 2003, Wang Xiaolin, a researcher at the Institute of Vertebrate Paleontology and Paleoanthropology of the Chinese Academy of Sciences, obtained a Manchurian crocodile fossil from a local villager in western Liaoning. When the villagers opened seven or eight layers of newspapers and said that they found a "crocodile" with a big belly, Wang Xiaolin and others were not surprised, because Manchurian crocodile fossils were quite common in western Liaoning, and the "big belly" said by the villagers may only be caused by squeezing or sliding when the fossils were buried. But in the dim light, several juvenile stone remains of Manchurian crocodiles inside the big belly on the fossil slab caught Wang Xiaolin's attention. And thus unveiled a cruel existential reality of prehistoric life. According to the fossil residue Wang Xiaolin told us a tragic story.
Manchurian crocodile restoration
In the Rehe biota more than 100 million years ago, the animal's food chain was disrupted due to volcanic eruptions and other factors. The dry season has been going on for a long time, there is not a trace of cloud, the sky is dazzlingly blue, and with the gray volcanic smoke, the sky over Western Liaoning is ominous. The mudflats by the lake are nearly dry, and after absorbing the smell of a large number of dead fish, they are filled with the smell of decay. The whole mudflat is lifeless, moving only a wedge-toothed Manchurian crocodile, its body is flat, there are webs between the toes, its epidermis texture is very similar to that of crocodile lizards, and its life habits may be similar to today's crocodiles. The survival of prehistoric animals was greatly threatened. The Manchurian crocodile, which is the hegemon of the lake, also feels the threat of starvation and death. In order to survive, it must find food today. Suddenly, the Manchurian crocodile found a litter of newborn small Manchurian crocodiles moving by the lake. The instinct to survive overwhelmed everything, and the hungry Manchurian crocodile showed its sharp teeth in front of these young crocodiles of the same kind that had just broken out of their shells. One by one, it bit off their young heads, and then swallowed in a flurry. However, it would not have imagined at the moment that this would be its last meal. Just a few hours later, the devourer was buried in volcanic ash along with 7 small lives that died prematurely. Survival, sometimes it's just so cruel...
Wang Xiaolin said that this prehistoric murder case is frightening. The phenomenon of voracious or intraspecific predation is a very specific animal feeding behavior. Compared with relatively higher vertebrates such as reptiles, birds and mammals, voracious homosexual behavior is more common in lower vertebrates and invertebrates, such as river crabs and giant river prawns are often eaten by their counterparts in the larval stage and molting. Among the higher vertebrates, there are fewer carnivorous species, but there are still at least 14 carnivorous mammals and a large number of reptiles and birds that perform this behavior. But rare evidence of such fossils has been found in the evolutionary history of vertebrates. To date, there are only two conclusive evidences: Late Cretaceous Mammothosaurus and Late Pleistocene Neanderthals, and controversial evidence includes Late Triassic Coelentosaurus.
Fossil specimen of the Manchurian crocodile
The following is the media report on this discovery at the time: the title of the report is "China found the earliest known food-loving "case" of the ancient Manchurian crocodile poisonous food 7 pups"
In times of food shortage, the report said, open the blood basin to their own kind - this is the means used by insects, fish, amphibians and other lower animals to ensure survival, and higher vertebrates rarely "kill this hand". However, a joint Scientific Team of China and the United States recently found a cruel guy in the fossil group in Western Liaoning: a wedge-toothed Manchurian crocodile actually swallowed 7 pups in one go! The latest (2005) publication of The Chinese Science Bulletin reports on the joint research results of the Institute of Vertebrate Paleontology and Paleoanthropology of the Chinese Academy of Sciences, the University of Kansas, and the Beijing Museum of Natural History. It is reported that this is also the earliest known "case" of the same kind of voracious species in the existing vertebrate specimens in the world. The Manchurian crocodile grew in the Early Cretaceous 120 million years ago and is less than half a meter long. In its abdominal cavity, scientists found 7 pups that had been digested to varying degrees. "Judging from the preservation of the bones, we ruled out the possibility of the Manchurian crocodile becoming pregnant, but it first bit off its head and then swallowed it one by one." Professor Wang Xiaolin, a member of the research team and the Institute of Vertebrate Paleontology and Paleoanthropology of the Chinese Academy of Sciences, told reporters that these 7 young crocodiles are almost the same, most likely from the same nest, but it is still unclear whether it eats its own cubs or the babies of other Manchurian crocodiles.
The Manchurian crocodile specimen found this time is a fossil record of the earliest vertebrates with the most direct and convincing voracious behavior of their counterparts. The specimen provides valuable information about the ecological environment, food chain and reproductive development behavior 120 million years ago.