"Prehistoric predators" eating dinosaur is the unusual thing

"Pig dog duck mouse" is in fact a crocodile, eat bar dinosaur is extraordinary things "prehistoric predators" collective debut

Beijing News weekly of the new knowledge

Celeno and he discovered ancient crocodile skull fossils, the Great Emperor crocodile, and can be placed in the hands of pet dogs crocodile.

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Recently, the famous "fossil hunters" Paul · celeno announced five new prehistoric crocodile fossils like modern crocodile-like to lie in ambush their prey in the water like a duck-like in the water filtration, like a dog running around looking for food, even with the same as male wild boar Tusk to prey on other animals for food, including some dinosaurs.

1 fossil Hunter finds new crocodile

Professor, University of Chicago explorers celeno (PaulSereno) is the world's most famous "fossil Hunter".

His most important record is found in the early 21st century 12 m long, weight up to 8 tons of "Emperor crocodile". Celeno and partner, McGill University help Larsen (HansLarsson)-member group long-term in the Sahara desert looking for crocodile fossils. In order to collect the crocodile fossils, celeno and his team needs to stand up to 51 ° c of temperature, in a few months are live on dry food. Logistical supply very challenging. In 2000 a visit, for example, they have few truck, tool, tents, 5 tonnes of gypsum, 226 kg water and can support 5 months of other supplies into the Sahara desert.

Now the most dry and unfriendly in the Sahara desert in the Mesozoic era when climate humid, biological exuberance, various dinosaur activities here.

While celeno's group in recent years continuous here found 5 species live in 1 million years ago of ancient crocodile fossils, many fossils from the old beaten together on crocodile then and very busy. Their findings in a recent journal of biology of the biology of keys (ZooKeys) and the November issue of the National Geographic published. 21 November, the national geographic, channel more special broadcast on the crocodile eating dinosaur era.

Dog crocodile fossils.

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2 occupy different environment location

In fact, the National Geographic channel program "is a purely" title "," crocodile eating dinosaur "isn't what the" news ".

Columbia University brussat study showed that now 2.51 billion years ago to 1.99 billion years ago, the ancestors of modern crocodile crocodile ankle early Dragon class and almost no dinosaur evolution speed differences, in other words, the dinosaurs are simply not the era of "boss", proceedings of the first Dragon class ankle but more powerful.

Newly discovered 5 crocodile new fossils still surprised that the scientific community, they varied morphology shows they have a wide variety of lifestyles, occupies a position of ecological systems.

The five new fossil of crocodile looks the most fierce is a place called "wild boar" crocodile crocodile.

Its height is 6 meters, with horns on his head, mouth and nose with armor, can be used as a sledgehammer blow its prey. Its most prominent features are three sets of dagger teeth can tear the flesh. It is clear that the "wild boar" alligator is one of the main food small dinosaurs. Patty crocodile is 6 meters in length, it has a pizza as thin and flat nose and scientist believes that it is in the water following motionless mouth wait a few hours, until the game into its mouth, and then use the pancake-like mouth "clip" live prey. There are three "little monsters", such as one-metre-long alligator "rat", four-legged ground that stood to insects and plants. It has a pair as the mouse-like large incisors, scientists think they used to dig out the food. The "duck crocodile" has a flat forward mouth, it will use that mouth in shallow everywhere find, filter for small fish and insects. Finally, the "dog" alligator, scientists think that it has a dog soft nose and also eat plants and insects, swimmer and running workhorse.

Duck crocodile's model.

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Wild boar-proceedings of the model.

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Larsen said: "we were surprised to be in the same place so many new species.

Each crocodile obviously have different menus, different behaviors that looked them to ecological systems have different masses, each with their own alligator sinensis have use of the surrounding environment. ”

3 brain smart and able to swim can run

Why these crocodile in 1 million years ago so busy? "

smart" may be one reason. Celeno use CT scans a duck crocodile and alligator's dog skull fossils, generate a digital model of the brain, also created the entity model. The result: the crocodile has a flat, scooped the forebrain, and now the brain health crocodile. Larsen said: "their brain function may be larger than are students crocodile slightly more complicated. ”

Rat crocodile recovery plan.

"Smart" seems to be not the only reason.

In order to better understand the crocodile, celeno came to the North Australia, where he observed wild freshwater crocodile, and capture their observations from celeno accidentally discovered a crocodile success: he found freshwater crocodile can like mammals, like "step forward", and access to running water, but can swim like a fish.

Long runs (gallop) and small step run (jog) pose completely different.

Quadruped in small step run time is four feet are touching the ground, and the great race is the forelimb hindlimb as a group, as a group, a loop can hear two groups before and after the interval is short. Long run can take full advantage of the waist length and strength of the stretch. In this process must be up and down the spine. FishSwimming in the water, is about activities of the body. This may just be a fortuitous choice. Fish landing, the first batch of terrestrial animals must have been about activities like fish. Now most amphibians and reptiles are so small step to run was thus evolution. And you learned to step forward in mammals, but about the ability of the spine is greatly restricted. Interpretation of the fossils, celeno assumes that these early crocodile is small, four-legged walking upright and will step forward to run animal. They wrote in the paper, these newly discovered crocodile will step forward to run on the ground, and can be used to swim tail, modern crocodile's two great success formula in 1 million years ago was already forming.

Interviews/reporter Liu Zheng