strange trackways leave behind by some of the world ’s great - ever dinosaurs have left paleontologists stymied by what they seem to intimate . Giant round footprint get hold in Texas clearly show that vast four - footed sauropods once stray the land here , and yet , they ’ve only discover set of prints from the two front feet .
Unless sauropod dinosaur were prone to doing handstand , scientists have another trace for why this may be so : the dinosaurs may have waded across a lake or river , using just their front feet to punt along the bottom .
In a Modern field published inIchnos , research worker from the Heritage Museum of the Texas Hill Country , the Houston Museum of Natural Sciences , and Purdue University hypothesize about what scenario could lead these prehistoric giants that needed four immensely unattackable leg to have their massive weightiness to have been possibly bi - foot lever .
The footprint – some measure 70 cm ( 27.5 inches ) across – were detect in a limestone target near Austin back in 2007 . The layer of stone they are in date to around 110 million class old . It ’s difficult to estimate a dinosaur ’s size or coinage just by footprints , but the size of these suggests it could be one of the three largest sauropod dinosaur found in this part of America : Astrophocaudia , Cedarosaurus , andSauroposeidon , the tallest dinosaur ever .
The idea that these massive creatures walked on two legs , and those being the front leg rather than the hind , is absurd , expert say . However , to find manus - only ( meaning just the forelimbs ) rails of large sauropods is not unheard of , though it is rare . The theory that they may have been create by a dinosaur “ swimming ” goes back to 1940 , when similar manus - only prints were found in an ancient river layer in Texas , back when sauropods were thought to be aquatic animate being .
However , the more dinosaur we dug up , the more we understood they were terrestrial tool , and manus - only footmark were probably to do with weight distribution . One of the prevalent theories was that the eye of mass for these large dinosaurs was toward their front , mean their front human foot would suffer the payload , creating deep impressions in the undercoat .
However , other sauropod footprints across Texas show all four feet , mean the hindfeet leave impressions just as cryptical as the front ones . These manus - only footprints were also oddly splayed at a distance further than other find . This propose that the bi - pedal behaviour was perhaps due to " strange motive power " by these animals , which lead the researcher back to the " swimming " sauropod dinosaur .
You might suppose it ’s inconceivable that a terrestrial creature that count as much as 60 tons could swim , but these dinosaur had huge lungs andair sacs in their os , which would make their body peculiarly light . However , the researchers hypothesise that the makers of these tracks were not quite swimming , but jampack through water that had been around shoulder joint height , using their front limbs to punt themselves along the bottom to wield control and balance .
" Although hypothesized unusual behaviour would not inevitably involve ‘ swim ’ , it is deserving count the theory that … manus - only sauropod trackways were made by dinosaurs that were wading in water late enough for their Almighty to stake , tear themselves along by their forefoot , while their hind leg float above the bottom , " they pen .
" Such a punting sauropod might then be able to glide with its soundbox supported by the water , thereby hold longer oblique paces and creating a wider trackway … If much of the dinosaur ’s weight was buoyed up by the piddle , this might also result in shallowly impressed manus prints . "
The researchers observe that until there is more grounds , either from stiff and other footprints discovered in this part of Texas , or other manus - only trackways in areas that were once and for all once water - log , this explanation can only remain a hypothesis , but we are with lead generator Dr James Farlow when he toldNew Scientist : " [ I]f you enquire me in my center of warmness what I would like to be true , I ’d like them to be punt . ”
