Five hundred million days ago , the Earth was a whole lot of sea . Underwater , theCambrian Explosionwas bringing a flurry of specialisation that put down the foundations for advanced animal phylum . The new creatures were not just multicellular blobs , but had many of the discover features of animate being today : eyes , stage , shell , and mandibles . One of these creatures appears to have been not only a trailblazer in eubstance figure , but also in lifestyle . It has been called a submarine and a taco , but its name isOdaraia alata .
Odaraiahad been first find 100 age ago in theBurgess Shale , a rich fossil deposition in the Canadian Rockies . It contains some of the old fossil of soft organic structure part ( 500 million old age old ! ) , providing many insights into what theCambrianworld looked like .
Most Welsh animals were part of the benthos , the ecosystem of the seafloor , butOdaraiawith its 20 - cm ( 7.9 - in ) long trunk may already have been swimming up the water column – to hunt . By consider 150 fossils ofOdaraia , Alejandro Izquierdo - López and Jean - Bernard Caron could make a elaborate reconstructive memory of what thisarthropodwould have looked like , and how it probably fertilise .
In this fossil,Odaraiareveals her taco shell.Image credit: photo by Jean-Bernard Caron, Royal Ontario Museum.
“ The head shield ofOdaraiaenvelops much one-half of its body including its pegleg , almost as if it were case in a subway system , ” order confidential information author Izquierdo - López in astatement . Its taco - corresponding appearance is only one of the remarkable features ofOdaraia . Of particular interest to the researchers are its mandibles and the many spine along its body .
Mandiblesare ubiquitous in the creation today , with almost half of all species having them , but they were a oddity in the Cambrian . The mandibles ofOdaraiaappear line with tooth , and with divot for the muscles to attach and control them . This grounds securesOdaraiaa spot among the pioneers of this soundbox part .
Even more utilitarian in target - capture than the mandibles are the spines . Along the length of the dead body ofOdaraia , the researchers found 30 sets of legs with small spines that could have created a mesh to capture target with . This suggest thatOdaraiacould have been a reprieve affluent , catch prey standardized to mesozooplankton in the net of its spine and then move it to its mouth .
Oh , and they also found thatOdaraiahad a tooth regulate like a trident at its mouth opening . They propose this resembles a stomachic tooth , which amazingly is a tooth that lobster and crabs have inside theirstomachs .
The authors highlight “ the office of regain anatomical information to improve ecological reconstructions ” .
This written report is published in theProceedings of the Royal Society B : Biological Sciences .
