Over a 100 ago , exotic - wait fossil were excavate in China , and their figure - eight anatomy was so strange , researchers have long puzzled over where they fit on the Sir Herbert Beerbohm Tree of life . Were they bivalved arthropods like trilobite or diffused - bodied , water - satisfy sac ? Now , a squad examining newly discovered , 500 - million - yr - sometime fossil belonging to this eccentric group reveal that they ’re actually unsighted pee tool with backbone - similar structures – give them nigh relatives to craniate and our distant cousins .
Though they were first discovered in 1911 , it was n’t until 1997 when the fossils were described and given a name : vetulicolians . These hourglass - shaped marine filter - feeders were about 15 centimeters long and swam the seas during the Cambrian . They ’ve since been discovered all over : Canada , Greenland , China and Australia .
Now , a team led byDiego García - Bellido from the University of AdelaideandJohn Paterson from the University of New Englandexamined refreshing anatomical details preserve in a set of Modern vetulicolian fossils discovered in coastal cliffs on Kangaroo Island off the coast of South Australia . These vetulicolians have a prospicient tail that ’s supported by a unwavering rod resembling a notochord – a backbone precursor that ’s unique to vertebrate .
The team trust they ’re one of the first representatives of our vertebrate first cousin , and they ’re closely allied to a group calledtunicates , which admit ocean squirts and salpa . All tunicates and humans likewise belong to the same phylum , Chordata .
" They were simple yet successful creatures , big in number and in distribution across the globe , ” Garcia - Bellido say in anews release . " Although not at once related to humans in the evolutionary line , we can confirm that these ancient water creatures are among our distant full cousin . ”
“ Some of our stranger removed cousins , ” Paterson adds in auniversity statement . These Kangaroo Island fossils warranted a new species , and the squad name itNesonektris aldridgei . “ Nesonektris ” is Greek for " island swimmer ” and the species name abide by Dick Aldridge , one of the pioneering vetulicolian researchers .
Thefindingswere issue inBMC Evolutionearlier this calendar month .
Images : University of Adelaide / South Australian Museum ( middle )
