Millipede-like creature lived in Scotland 425 million years ago
Thomson Reuters ·
Kampecaris
obanensis was about 2.5 centimetres long with a segmented body. It
resembled modern millipedes, but was a member of an extinct group and is
not ancestral to millipedes alive today. (British Geological Survey/Reuters)
A
fossilized millipede-like creature discovered in Scotland may represent
the oldest-known land animal, a humble pioneer of terrestrial living
425 million years ago that helped pave the way for the throngs that
would eventually inhabit Earth's dry parts.
Researchers said the fossil of the Silurian Period creature, called Kampecaris obanensis and
unearthed on the island of Kerrera in the Scottish Inner Hebrides,
inhabited 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 2.5 centimetres 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.
This
is the coastline of Kerrera, a Scottish island where the fossil was
found. The animal inhabited a lakeside environment and likely ate
decomposing plants. (Michael Brookfield/Handout/Reuters)
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 likes mosses
approximately 450 million years ago. The later advent of plants with
stems like Cooksonia helped usher in more complex terrestrial
ecosystems.
The
first land vertebrates — amphibians that evolved from fish with brawny
fins that inhabited shallow waters — showed up about 375 million years
ago — ancestors of the reptiles, birds and mammals alive today including
our species, Homo sapiens, which first appeared about 300,000 years ago.
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