九九视频精品全部免费播放-九九视频免费精品视频-九九视频在线观看视频6-九九视频这-九九线精品视频在线观看视频-九九影院

It turns out those Tyrannosaurus Rex chase scenes in Jurassic Parkmay not be reality kings hiding from parents full videos teen sexso realistic after all.

We hate to break it to you but: the famed dinosaur couldn't run, according to new research from Manchester University. In other words, everything you thought you knew about the T. rex chasing down its prey could be wrong.

The study, which used multi-body dynamic analysis and skeletal stress analysis — two bio-mechanical techniques — found that the T. rex's legs wouldn't have been able to handle running. Evidence shows that the T. rex was actually limited to walking, and wouldn't have been able to run due to its body mass.

Instead of the hyper-fast speeds we see in the movies, the study initially found that the T. rex could travel at a maximum speed of roughly 19 MPH (30 km/H). This was eventually lowered to 12 MPH (20 km/H) once researchers tested skeletal strength, according to the BBC.

The study, headed by Professor William Sellers at Manchester's School of Earth and Environmental Sciences, claims that the models used for the study "are currently the most anatomically complete reconstructions ever attempted."

Sellers told the BBCthat based on the study's "highly realistic computer models," running would have been impossible for the T. rex, because it's skeleton would have been too weak.

"That means that T. rexwas actually quite slow and therefore not a pursuit predator," he said.

Another study, separately published by Nature Ecology & Evolution, seems to back up Manchester's findings, as it concludes that the largest animals generally cannot accelerate as fast as smaller animals can.

"Put simply, small to intermediately sized animals accelerate quickly and have enough time to reach their theoretical maximum speed, whereas large animals are limited in acceleration time and run out of readily mobilizable energy before being able to reach their theoretically possible maximum," the study says.

That said, the study out of Manchester notes that people should be cautious about the researcher's findings.

"These results improve on those obtained by previous biomechanical work by excluding some of the previously plausible values and thereby reducing the range of uncertainty but many of the previous caveats still apply," the study said.