Geoscientists and paleontologists working near Yiling, central China have discovered a previously unknown species of a millipede-like creature etched into a local rock formation which they estimate to be over half-a-billion years old.
The creature, named the ‘Yilingia spiciformis’, or ‘Spiky Yiling Bug’ – in honour of the region where it was found, and based on its spiky appearance, is believed to have died between 551 and 539 million years ago, fossilising right along the trail it was forging before its death.
The complex creature, complete with legs, could grow to over 27 centimeters, was bilaterally symmetrical, is thought to have contained a crab-like exoskeleton, a centipede-like segmented body and spider-like joined limbs.
In a study published in Nature, scientists explained that the discovery of the Spiky Yiling Bug has exciting implications for how animal life evolved on our planet.
Specifically, the fossil seems to shore up earlier hypotheses about the existence of complex animals capable of engaging in directional movement before the Cambrian Explosion, an event which took place approximately 541 million years ago and saw the speedy (in evolutionary terms) appearance of a variety of complex animals.
The Yiling fossils provide “direct supporting evidence” of movement by a segmented animal in the pre-Cambrian period, Dr. Shuhuai Xiao, study coauthor and professor at the geosciences department at Virginia Tech, told AFP.
“Yilingia spiciformis is thus far the oldest known segmented animal that was demonstrably capable of directional movement,” Xiao noted.
Dr. Zhe Chen, another of the study’s authors, said the Spiky Yiling Bug may in fact be the earliest segmented bilaterian animal (i.e. bilaterally symmetrical animals with a head, mouth and an anus) known to man.
Dr. Rachel Wood, a geoscientist from the University of Edinburgh who peer-reviewed the study, called the fossil find “remarkable,” saying that it has the potential to fill in gaps in scientists’ understanding of animal movement before the Cambrian Period.
“Such preservation is unusual and provides considerable insight into a major step in the evolution of animals,” Wood said.
Xiao and his colleagues now plan to explore further “how animal locomotion behaviours may have responded to environmental changes,” and to explain the function of such movement – i.e. to see if it was based on a search for food, oxygen, mates, or a dash to escape possible predators.
Pointing to humanity’s own impact on the Earth, Dr. Xiao stressed that it has been based almost entirely on our ability to move. Accordingly, Xiao suggested that “when and how animal locomotion evolved defines an important geological and evolutionary context of anthropogenic impact on the surface of the Earth.”