scientist have name markings in a unexampled curing of trace fossils that suggest complex life existed earlier than antecedently thought . It is an importantdiscoverythat could all alter what we think we knew about the evolutionary timeline .
The fogy were found in sediment in the Corumbá realm of western Brazil , and are over half - a - billion years old . The subject field is issue in the journalNature Ecology and Evolution .
" This is an especially exciting find due to the age of the stone – these fogy are found in stone layers which actually pre - date the Old fossils of complex animals – at least that is what all current fossil records would suggest , " explained Dr Russell Garwood , from Manchester ’s School of Earth and Environmental Sciences , in astatement .
Trace fossils are fossils that show sign of life , rather than being the remains of life themselves . Think footprint , tracks , and feces instead of osseous tissue fragment and fingernails . In this particular compositor’s case , the rocks have embossment allow by a animal burrowing through the deposit one C of millions of year ago . It is , scientists think , the earliest sign of an organism with muscle control and the ability to actively move .
The scientist believe the burrow were work by " nematoid - alike organisms " , which look a lot like modern - day roundworm . They might not fathom all that telling , but they are considered complex life course and , like human being , add up under a group of brute called bilaterians . Bilaterians have one layer of symmetary , whereas simple-minded creatures , including jellyfish , have multiple . archaeological evidence tends to be quite a bit younger , with the first fossil appearing in the Cambrian period ( 545 million to 495 million years ago ) .
" Our raw fossils show that complex animals with muscle control were around about 550 million years ago , and they may have been drop previously because they are so tiny , " said Luke Parry , lead writer from the University of Bristol .
They really are tiny . From the size of the tunnel , scientist have ferment out that these ancient creature valuate just 40 to 300 micrometers – about the breadth of a string of human hair . They would have impress around the sediment , wiggling and bequeath behind burrow as they go .
The thing that is really fascinating is their age . The burrows were fossilized during a point known as the Ediacaran - Cambrian transition ( around 541 million year ago ) , an important turn point in time in evolutionary story . To give that some setting : The first dinosaur appear around 230 million years ago during the Mesozoic Era , and innovative Homo sapienshave only been around for the past 200,000 or so eld .
" The evolutionary events during the Ediacaran - Welsh transition are unparalleled in Earth history,“saidGarwood . " That ’s because current fogy records suggest that many animal groups active today appeared in a really short sentence interval . "
" Our discovery highlights an undiscovered windowpane for tracking animal organic evolution in deep time , " Parryadded .
