Imagine a world where giant millipedes measuring up to nine feet in length roamed the Earth. While it may sound like something out of a science fiction movie, this incredible scenario actually existed during the Carboniferous Era, about 100 million years before the age of dinosaurs. Recent archaeological findings in Northumberland, England have unveiled the fossilized remains of a car-sized prehistoric millipede, the largest ever discovered, shedding light on the existence of these colossal creatures.
Discovered by chance, this fossilized creature is a remarkable find. It would have weighed a staggering 110 pounds and had a body spanning an impressive nine feet. The findings were published in the Journal of the Geological Society on December 20, 2021, revealing this ancient Arthropleura specimen as the largest-known invertebrate ever found.
The enormous millipedes lived approximately between 299 and 359 million years ago, as reported by Science Alert. While experts were aware of their existence, this particular fossil has provided the first concrete evidence of their massive size. The preserved exoskeleton of the creature confirmed its previously unknown dimensions. However, there is still much more to learn about these ancient creatures.
Lead author Neil Davies explains that finding such giant prehistoric millipede fossils is exceptionally rare. Once these creatures died, their bodies would typically disarticulate, making it challenging to find well-preserved fossils. It is believed that the discovered fossil is a molted carapace that the millipede shed as it grew. Notably, a fossilized head has not yet been found, leaving many unanswered questions about the species.
Two smaller Arthropleura specimens were previously found in Germany, indicating that these creatures inhabited both swamplands and woodlands, similar to the Northumberland discovery. The excavation of the car-sized prehistoric millipede was a complete stroke of luck. A fragmented block of sandstone sitting on a beach cracked open, exposing the perfectly preserved exoskeleton. The fossil was so massive that it took a team of four researchers to carry it up the cliff face.
This find was particularly significant because the location in Northumberland is not typically known for fossils. The fact that the boulder had fallen from a cliff and cracked open to reveal the millipede’s remains left researchers in awe. It is extremely rare for shed material to be preserved so well in the fossilization process. Moreover, in comparison to other Arthropleura fossils found in Germany, this discovery stands out as the largest.
The fossil suggests that soon after molting, the millipede became filled with sand, fell into a small river, and quickly got entombed in sediment. Smaller examples of Arthropleura had a common width-to-length ratio of 4.78. Based on the width of this fossil, which measures 55 cm, it is estimated to be 2.63 meters long. These millipedes would have been the largest animals on land during the Carboniferous Era.
Prior to the discovery of this exoskeleton, researchers relied primarily on fossilized footprints to understand the species. It was believed that the colossal size of these creatures was due to higher oxygen levels in the atmosphere during the Carboniferous Period. However, recent studies have shown that increased oxygen levels were not the primary factor. Neil Davies suggests that their diet may have played a significant role in their size. These millipedes may have fed on nutritious nuts, seeds, other invertebrates, and possibly even small vertebrates like amphibians.
Despite the progress made in understanding Arthropleura, many questions remain unanswered. The exact number of legs the species possessed is still uncertain. While other more complete fossils had 32 segments, it is unknown whether the creature had two legs per segment, totaling 64, or two legs for every other segment, totaling 32. The discovered fossil indicates that it had at least 20 legs. These fascinating creatures thrived for 45 million years until the rise of reptiles during the Permian Period led to their extinction.