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A tidy , 10 - foot - long ( 3 meters ) crocodile relation had an unpaired way of capture around 120 million long time ago in what is now South Korea . The huge beast walked on its two hind legs like aT. male monarch , research worker read after examine footprints left behind by the reptile .

There are no known fossilized bones of this strangecrocodile , but dozens of its up to 120 million year - sure-enough footprint , admit one with peel impression , are preserved in stone .

The two-legged crocodile relative, which left the fossil footprints in what is now South Korea, may have looked like this.

The two-legged crocodile relative, which left the fossil footprints in what is now South Korea, may have looked like this.

" For the first time , we have proof that some of the giant crocodiles of theCretaceouswere bipedal and really plan like the carnivorous dinosaurs , " study co - researcher Martin Lockley , professor emeritus of geology at the University of Colorado Denver , told Live Science .

bear on : picture : Dinosaur tracks break Australia ’s ' Jurassic Park '

research worker found the fossilise footprints ahead of a construction project . Researchers named it the Sacheon Jahye - ri tracksite , as it ’s west of Sacheon City in South Gyeongsang Province .

Photos and 3D images of the tracks found in South Korea.

Photos and 3D images of the tracks found in South Korea.

The cart track marks are big , up to 9.5 inch ( 24 centimeters ) long , the researchers said . The crocodile also likely " had legs about the same peak as human adult leg , " study senior researcher Anthony Romilio , a paleontologist at the University of Queensland in Australia , aver in a statement .

After Korean researchers transferred the trackways to a laboratory , they invite Lockley to look at the effect in November 2019 . Initially , the team thought that these print might belong to a giantpterosaur , but the instant Lockley escort them , he said he sleep together they were from a crocodile relative .

antecedently , Lockley had study crocodile print from theJurassic period(199 million to 145 million years ago ) . The crocodile that leave those print was much smaller — its tracks were about 1 in , or 2.5 centimeters long — and it walked on all fours . Even so , those prints were remarkably alike to the newly discovered ones , he tell .

Photos and 3D images of the tracks found in South Korea.

Photos and 3D images of the tracks found in South Korea.

This realization triggered another memory ; Lockley and his colleagues had release a study in 2012 in the journalIchnoson what they thought were jumbo pterosaur tracks from the Cretaceous time period of Korea . At the metre , however , they knew something was weird about the tracks , so they called them " enigmatic . " reckon back , Lockley realized that just like the newfound path , the enigmatical prints are most probable from a two - legged crocodile .

work together , the team found myriad hint that the newfound trackway belonged to a crocodile and not a flying reptile . For example , pterosaurs in all likelihood used their fender while walking , meaning they walk on all fours . But no handprints ( or wing photographic print , for that matter ) were found . In summation , the skin impression obtain on a heel mark resembled that of a crocodile , Lockley said . Moreover , the photographic print had robust digits and impression of pads and joints that looked just like those from a crocodile , he said .

That said , it ’s understandable that the researchers initially thought these trackways belonged to elephantine pterosaurs . " distinctive crocodiles walk in a squat position and create trackways that are wide , " subject lead investigator Kyung Soo Kim , a paleoecologist at the Chinju National University of Education in South Korea , said in the command . " strangely , our trackways are very minute expect — more like a crocodile balancing on a mingy - rope . "

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" When [ the footprints were ] combine with the lack of any tail - drag marks , it became clear that these creatures were motivate bipedally , " Kim said .

The team named the newfound fossil printsBatrachopus grandis . ( Trace fossils , such as fossilized trackways and burrow , are given scientific names , just as animals are . )

During the lower Cretaceous , the track site was a lake hem in by mirky ground , " which made for making good cart track , " Lockley state Live Science . It ’s difficult to say how these prints were preserved , but perhaps the animate being left the prints in tight clay just before the lake retreated , allowing the print to dry and harden . When the water level uprise again , clay and okay silt could have covered and uphold the tracks , Lockley said .

An artist�s reconstruction of a comb-jawed pterosaur (Balaeonognathus) walking on the ground.

Or , maybe the mud was diffused and soupy , like warm ice pick , but the earth under the " glass emollient " was hard , he say . The crocodile could have squished through the muck and allow an impression on the hard ground underneath , which would have been instantly buried and preserved by the " ice cream " when the beast lifted up its foot , Lockley said .

The study was published online yesterday ( June 11 ) in the journalScientific Reports .

in the first place publish onLive scientific discipline .

a researcher compares fossil footprints to a modern iguana foot

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