Looking at an earthworm that ’s been dumped on the street by a bird , you might not think much of the annelids , but the reality is these animals are one of the largest and most successful phylum of animals awake today . They ’ve rule both mundane and nautical ecosystem , and now the analysis of some unmistakably erstwhile and well - preserved specimens has discover they emerged on Earth around 200 million years earlier than previously think .
The find follows the analysis offossilsof the annelid wormIotuba chengjiangensis , outre worms that go steady back 515 million year and look a snatch like a chorizo stick with a party chapeau on top . As a cage dirt ball , it would ’ve ducked its head in and out of its flakey tasselly bristle cage .
The fossils show evidence of a digestive organization andkidneysinI. chengjiangensis , demonstrating to the researchers that they were surprisingly complex . It seems that the more complex body plan of other annelid emerge much earlier than expected , by about 200 million age , and that they did n’t drop out on the Cambrian Explosion as had been previously propose .
“Ain’t no party like a Cambrian explosion party.” Image credit: Zhang Zhifei
“ We know that the main animal lines we see today emerged during theCambrian detonation , but we always thought annelidan worms were late to the party , and their major subgroups did n’t set out to diversify until nearly 200 million years after , ” said study co - author Dr Martin Smith of the Department of Earth Sciences , Durham University , in astatement .
“ But the amazingly preserved fossils we have canvass and the structure of these amazing little creatures dispute this picture , and show that annelid worms – includingIotuba chengjiangensis – seemed to surveil the formula of events initiated by the Cambrian explosion [ … ] It turns out they were n’t late to the company at all , they were just hide out in a side room . ”
The discovery of an annelid ancestor so betimes in evolutionary time indicates that there are many ghost lineages from the eld that followed that we ’ve yet to find .
“ These class are like the top rundle on an evolutionary ladder , ” explicate Smith . “ For these group to have appeared so early in the day , there must have been a spectacular unseen origin of innovative annelid diversity in the heat of the Welsh explosion . ”
“ It turns out that many of the annelids we cognise and love today may have begun to develop much sooner than we think . ”
Gather your early birds , we ’re run worm hunting .
The report was publish in the journalProceedings of the Royal Society B.
