Fossils

[Dzombo]

Does it mean that they all died together in that place?

Yes

[Richprins]

Oh so these things are actually found locally there!

[Lisbeth]

They died during the Jurassic era and lived in the sea. The place was under water

[Dzombo]

Yes, the area was a shallow sea
The Ammonites died on mass and got covered in silt. Eventually that solidified to form rock.
Over the millennia, due to plate tectonics that area raised up above sea level to become land that it is today.

[Lisbeth]

Billion-year-old Chinese seaweed is oldest green plant fossil

By Reuters• 25 February 2020

WASHINGTON, Feb 24 (Reuters) - Scientists have spotted in rocks from northern China what may be the oldest fossils of a green plant ever found, tiny seaweed that carpeted areas of the seafloor roughly a billion years ago and were part of a primordial revolution among life on Earth.

Researchers on Monday said the plant, called Proterocladus antiquus, was about the size of a rice grain and boasted numerous thin branches, thriving in shallow water while attached to the seafloor with a root-like structure.

It may seem small, but Proterocladus – a form of green algae – was one of the largest organisms of its time, sharing the seas mainly with bacteria and other microbes. It engaged in photosynthesis, transforming energy from sunlight into chemical energy and producing oxygen.

“Proterocladus antiquus is a close relative of the ancestor of all green plants alive today,” said Qing Tang, a Virginia Tech post-doctoral researcher in paleobiology who detected the fossils in rock dug up in Liaoning Province near the city of Dalian and lead author of the study published in the journal Nature Ecology & Evolution.

Earth’s biosphere depends heavily on plants for food and oxygen. The first land plants, thought to be descendents of green seaweeds, appeared about 450 million years ago.

There was an evolutionary shift on Earth perhaps 2 billion years ago from simple bacteria-like cells to the first members of a group called eukaryotes that spans fungi, plants and animals. The first plants were single-celled organisms. The transition to multicellular plants like Proterocladus was a pivotal development that paved the way for the riot of plants that have inhabited the world, from ferns to sequoias to the Venus flytrap.

Proterocladus is 200 million years older than the previous earliest-known green seaweed. One of its modern relatives is a type of edible seaweed called sea lettuce.

Proterocladus represents the oldest unambiguous green plant fossil. Fossils of possible older single-celled green plants are still a matter of debate.

Plants were not the first to practice photosynthesis. They had an ancestor that apparently acquired the photosynthesis cellular apparatus from a type of bacteria called cyanobacteria.

This ancestor of all green plants gave rise to two major branches, one of them includes some aquatic plants and all land plants while the other – the group to which Proterocladus belongs – is made up exclusively of aquatic plants.

“Proterocladus antiquus,” Virginia Tech paleobiologist and study co-author Shuhai Xiao said, “is the sister of the evolutionary great, great grandmother of all green plants alive today.”

(Reporting by Will Dunham; Editing by Sandra Maler)

[Dzombo]

Interesting.

Thanks for posting

[Lisbeth]

[Dzombo]

My latest acquisition

Glossopteris - leaves of a tree like plant
Permain - 298 mya
Australia

This was one of the fossils that was used to prove continental drift.
Very similar specimens have been found in Australia, South Africa, Brazil, Antarctica, and India.
Knowing what we do about the direction in which the continents are currently moving, extrapolating backwards, scientists were able to prove that they were all joined as the super-continent - Gondwana

25cm across

A.jpg (99.38 KiB) Viewed 2156 times

[Richprins]

Looks just like today!

[Lisbeth]

Very clear