3 APRIL 2021
Life was trying, but it wasn t working out. As the Late Devonian period dragged on, more and more living things died out, culminating in one of the greatest mass extinction events our planet has ever witnessed, approximately 359 million years ago.
The culprit responsible for so much death may not have been local, scientists say. In fact, it might not have even come from our Solar System.
Rather, a study published in August last year, led by astrophysicist Brian Fields from the University of Illinois Urbana-Champaign, suggests this great extinguisher of life on Earth could have been a distant and completely foreign phenomenon – a dying star, exploding far across the galaxy, many light-years away from our own remote planet.
Sediment records shows new forests sparked the Devonian Mass Extinction
There was a link between new growth and an explosion of plankton blooms
Experts suggests new vegetation grew worldwide some 360M years ago
This pushed new nutrients into the soil that trickled into oceans in waves
It was enough to fuel plankton that grew to massive sizes around the globe
The blooms then devoured all the oxygen, suffocating marine animals
Nikk Ogasa, Contributor
( Inside Science ) Lub-dub. Lub-dub. Lub-dub.
Like the pulse of a throbbing heart, death beat down upon the seas around 376 million to 360 million years ago. During this time over 70% of animal species disappeared, most of which lived in the ocean. These creatures perished in waves of extinction as oxygen levels in the water oscillated and the downward swings repeatedly suffocated the seas. It was the most devastating period of the Late Devonian Mass Extinction one of the five largest extinctions to ever plague the planet. But what triggered these pulses of death has remained a hotly debated topic. Now, scientists believe that the earth s orbital cycles and the emergence of the first forests may have converged to produce this fatal rhythm.
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IMAGE: Artist s reconstruction showing the life stages of the fossil lamprey Priscomyzon riniensis. It lived around 360 million years ago in a coastal lagoon in what is now South Africa. Clockwise. view more
Credit: Kristen Tietjen
Ottawa, March 10, 2021 - A new study of fossilized lampreys dating from more than 300 million years ago is challenging a long-held theory about the evolutionary origin of vertebrates (all animals with a backbone). The findings are published March 10 in the science journal
Nature.
Lampreys are ancient, jawless, eel-like fishes that arose around half a billion years ago and they have long provided insights into vertebrate evolution. Now, scientists with the Canadian Museum of Nature, the University of Chicago and the Albany Museum in South Africa are reporting their analysis of dozens of tiny fossils that track the life stages and growth of ancient lampreys, from hatchlings to juveniles to adults.