A fossilized millipede-like creature discovered in Scotland may represent the oldest-known land animal. It’s believed the animal, called Kampecaris, lived on earth 425 million years ago.
Researchers said the animal lived in a lakeside environment and likely ate decomposing plants. Fossils of the oldest-known plant with a stem, called Cooksonia, were found in the same ancient lake region as Kampecaris.
While Kampecaris is the earliest land animal known from a fossil, soil worms are believed to have preceded it, appearing perhaps 450 million years ago, according to paleontologist Michael Brookfield of the University of Texas and the University of Massachusetts Boston, lead author of the research published this month in the journal Historical Biology.
Kampecaris, about an inch (2.5 cm) long with a segmented body, resembled modern millipedes but was a member of an extinct group and is not ancestral to millipedes alive today. Its legs were not preserved in the fossil.
It was an arthropod, a broad group that includes insects, spiders, millipedes, centipedes and crustaceans like crabs and shrimp.
Life first evolved in the world’s oceans, with an explosion of diversity beginning roughly 540 million years ago. It took quite some time for life to emerge onto land, beginning with plants like mosses approximately 450 million years ago.
The first land vertebrates showed up about 375 million years ago – ancestors of the reptiles, birds and mammals alive today, including human species, which first appeared about 300,000 years ago.