Half a billion years ago, the continents were quiet. Earth’s animals—represented largely by shelled mollusks, armored arthropods, and a smattering of wriggly, jawless fish—breathed with gills, not lungs, and hunted their prey at sea.

But sometime, possibly during the Silurian (the geologic period spanning 443 million to 416 million years ago) an intrepid creature, likely equipped with sturdy limbs and a set of gas-cycling tubes that could leech oxygen from air, decided to crawl ashore. In habitually venturing out of the ocean, this animal paved a habitat-hopping path for countless lineages of land-dwellers to come—including the one that eventually led to us.

Though Parioscorpio may have spent some of their time at sea, bits of their anatomy, including internal structures used for breathing and digesting food, hint that these ancient animals were capable of scuttling ashore—perhaps, even, to hunt the few creatures that preceded them on land.

Together with other, younger fossils from the same geologic period, the ancient arachnids suggest that scorpions have looked and acted in much the same way ever since they first appeared on Earth.

But Brandt, Prendini and Wendruff are all hesitant to dub Parioscorpio a pure landlubber like the more recent members of its lineage. While the fossils’ respiratory and circulatory systems hint that these scorpions were probably capable of breathing air, that doesn’t mean they actually did—part-time, full-time or otherwise. “There isn’t anything that unambiguously tells you whether they were fully aquatic, terrestrial or amphibious,” Prendini says. Horseshoe crabs, for instance, favor the salty ocean, but are known to make occasional forays onto land, where they can remain for up to four days.

https://www.smithsonianmag.com/science-nature/worlds-oldest-scorpions-437-million-year-old-fossils-180973975/

PermeateFree said:

Half a billion years ago, the continents were quiet. Earth’s animals—represented largely by shelled mollusks, armored arthropods, and a smattering of wriggly, jawless fish—breathed with gills, not lungs, and hunted their prey at sea.

But sometime, possibly during the Silurian (the geologic period spanning 443 million to 416 million years ago) an intrepid creature, likely equipped with sturdy limbs and a set of gas-cycling tubes that could leech oxygen from air, decided to crawl ashore. In habitually venturing out of the ocean, this animal paved a habitat-hopping path for countless lineages of land-dwellers to come—including the one that eventually led to us.

Though Parioscorpio may have spent some of their time at sea, bits of their anatomy, including internal structures used for breathing and digesting food, hint that these ancient animals were capable of scuttling ashore—perhaps, even, to hunt the few creatures that preceded them on land.

Together with other, younger fossils from the same geologic period, the ancient arachnids suggest that scorpions have looked and acted in much the same way ever since they first appeared on Earth.

But Brandt, Prendini and Wendruff are all hesitant to dub Parioscorpio a pure landlubber like the more recent members of its lineage. While the fossils’ respiratory and circulatory systems hint that these scorpions were probably capable of breathing air, that doesn’t mean they actually did—part-time, full-time or otherwise. “There isn’t anything that unambiguously tells you whether they were fully aquatic, terrestrial or amphibious,” Prendini says. Horseshoe crabs, for instance, favor the salty ocean, but are known to make occasional forays onto land, where they can remain for up to four days.

https://www.smithsonianmag.com/science-nature/worlds-oldest-scorpions-437-million-year-old-fossils-180973975/

> After wearily sifting through troves of trilobites—early marine arthropods that dominate many excavation sites—Wendruff, then a graduate student, was astounded to see “these tiny little things that looked like scorpions,” he recalls. “And that’s what they were.”

> “It’s always exciting to see a new ‘oldest,’” says Danita Brandt, an arthropod paleontologist at Michigan State University who wasn’t involved in the study. “This one is particularly exciting because it’s an organism living at this very interesting transition from water to land.”

Agree.

Tentative chart of evolution?
Anomalocaris to Eurypterid to Sea Scorpion to Land Scorpion to Spider to Insect (springtail) to Flying Insect?

mollwollfumble said:

PermeateFree said:

Half a billion years ago, the continents were quiet. Earth’s animals—represented largely by shelled mollusks, armored arthropods, and a smattering of wriggly, jawless fish—breathed with gills, not lungs, and hunted their prey at sea.

But sometime, possibly during the Silurian (the geologic period spanning 443 million to 416 million years ago) an intrepid creature, likely equipped with sturdy limbs and a set of gas-cycling tubes that could leech oxygen from air, decided to crawl ashore. In habitually venturing out of the ocean, this animal paved a habitat-hopping path for countless lineages of land-dwellers to come—including the one that eventually led to us.

Though Parioscorpio may have spent some of their time at sea, bits of their anatomy, including internal structures used for breathing and digesting food, hint that these ancient animals were capable of scuttling ashore—perhaps, even, to hunt the few creatures that preceded them on land.

Together with other, younger fossils from the same geologic period, the ancient arachnids suggest that scorpions have looked and acted in much the same way ever since they first appeared on Earth.

But Brandt, Prendini and Wendruff are all hesitant to dub Parioscorpio a pure landlubber like the more recent members of its lineage. While the fossils’ respiratory and circulatory systems hint that these scorpions were probably capable of breathing air, that doesn’t mean they actually did—part-time, full-time or otherwise. “There isn’t anything that unambiguously tells you whether they were fully aquatic, terrestrial or amphibious,” Prendini says. Horseshoe crabs, for instance, favor the salty ocean, but are known to make occasional forays onto land, where they can remain for up to four days.

https://www.smithsonianmag.com/science-nature/worlds-oldest-scorpions-437-million-year-old-fossils-180973975/

> After wearily sifting through troves of trilobites—early marine arthropods that dominate many excavation sites—Wendruff, then a graduate student, was astounded to see “these tiny little things that looked like scorpions,” he recalls. “And that’s what they were.”

> “It’s always exciting to see a new ‘oldest,’” says Danita Brandt, an arthropod paleontologist at Michigan State University who wasn’t involved in the study. “This one is particularly exciting because it’s an organism living at this very interesting transition from water to land.”

Agree.

Tentative chart of evolution?
Anomalocaris to Eurypterid to Sea Scorpion to Land Scorpion to Spider to Insect (springtail) to Flying Insect?

This one is from way back in 2014, but you might be interested.
“Insect Family Tree Maps 400-Million-Year Evolution” from https://www.livescience.com/48663-insect-family-tree-evolution.html

Among the stories that can be told using the new tree is the origin story of insects. Fossil evidence suggests that the first insects lived about 412 million years ago, during the Early Devonian Period. But the researchers’ phylogenetic data indicates that the largest group of insects, hexapoda, may have evolved even earlier, around 479 million years ago, during the Early Ordovician Period.

The insect family tree is mapped in https://cdn.mos.cms.futurecdn.net/buFb9WFFVn4tR2j5RrvP8U.jpg

It gives times in Ma, but I don’t see scorpions mentioned. Protura and speleonectes are nothing like arachnids, so scratch that idea.

Not sure how well I believe the following chart, also from 2014, but it does definitely remove the possibility that insects descended from spiders. Horseshoe crabs are similar to trilobites. It does have close to the right age for the “world’s oldest land scorpion”, roughly 437 Ma.

mollwollfumble said:

mollwollfumble said:

PermeateFree said:

Half a billion years ago, the continents were quiet. Earth’s animals—represented largely by shelled mollusks, armored arthropods, and a smattering of wriggly, jawless fish—breathed with gills, not lungs, and hunted their prey at sea.

But sometime, possibly during the Silurian (the geologic period spanning 443 million to 416 million years ago) an intrepid creature, likely equipped with sturdy limbs and a set of gas-cycling tubes that could leech oxygen from air, decided to crawl ashore. In habitually venturing out of the ocean, this animal paved a habitat-hopping path for countless lineages of land-dwellers to come—including the one that eventually led to us.

Though Parioscorpio may have spent some of their time at sea, bits of their anatomy, including internal structures used for breathing and digesting food, hint that these ancient animals were capable of scuttling ashore—perhaps, even, to hunt the few creatures that preceded them on land.

Together with other, younger fossils from the same geologic period, the ancient arachnids suggest that scorpions have looked and acted in much the same way ever since they first appeared on Earth.

But Brandt, Prendini and Wendruff are all hesitant to dub Parioscorpio a pure landlubber like the more recent members of its lineage. While the fossils’ respiratory and circulatory systems hint that these scorpions were probably capable of breathing air, that doesn’t mean they actually did—part-time, full-time or otherwise. “There isn’t anything that unambiguously tells you whether they were fully aquatic, terrestrial or amphibious,” Prendini says. Horseshoe crabs, for instance, favor the salty ocean, but are known to make occasional forays onto land, where they can remain for up to four days.

https://www.smithsonianmag.com/science-nature/worlds-oldest-scorpions-437-million-year-old-fossils-180973975/

> After wearily sifting through troves of trilobites—early marine arthropods that dominate many excavation sites—Wendruff, then a graduate student, was astounded to see “these tiny little things that looked like scorpions,” he recalls. “And that’s what they were.”

> “It’s always exciting to see a new ‘oldest,’” says Danita Brandt, an arthropod paleontologist at Michigan State University who wasn’t involved in the study. “This one is particularly exciting because it’s an organism living at this very interesting transition from water to land.”

Agree.

Tentative chart of evolution?
Anomalocaris to Eurypterid to Sea Scorpion to Land Scorpion to Spider to Insect (springtail) to Flying Insect?

This one is from way back in 2014, but you might be interested.
“Insect Family Tree Maps 400-Million-Year Evolution” from https://www.livescience.com/48663-insect-family-tree-evolution.html

Among the stories that can be told using the new tree is the origin story of insects. Fossil evidence suggests that the first insects lived about 412 million years ago, during the Early Devonian Period. But the researchers’ phylogenetic data indicates that the largest group of insects, hexapoda, may have evolved even earlier, around 479 million years ago, during the Early Ordovician Period.

The insect family tree is mapped in https://cdn.mos.cms.futurecdn.net/buFb9WFFVn4tR2j5RrvP8U.jpg

It gives times in Ma, but I don’t see scorpions mentioned. Protura and speleonectes are nothing like arachnids, so scratch that idea.

Not sure how well I believe the following chart, also from 2014, but it does definitely remove the possibility that insects descended from spiders. Horseshoe crabs are similar to trilobites. It does have close to the right age for the “world’s oldest land scorpion”, roughly 437 Ma.

Don’t mind you talking to yourself, but when you think aloud in print it becomes a little confusing.