The First Land Plants
The first land plants appeared around 470 million years ago, in the Ordovician Period. Their arrival seems to have occurred not just in one place, but simultaneously in several places around the globe. These were basically very primitive mosses, similar to the modern liverworts.
Once known collectively as psilophytes, they have been separated into multiple orders by more recent studies that have pinpointed key differences. Remains have been found in the form of dendrolytes - carbonized, mineralized and petrified remnants. These small plants were tiny and leafless, with dichotomous branching. They were often covered in scales and propagated by means of spores.
These early plants did not have roots, so they most likely grew in close connection to water, such as the edges of swamps and bogs. They also didn't have the vascular system of modern plants, though they were able to transport water and minerals internally by means of other specialized tissues.
In the Odovician, most life was sea life.
Some scientist link the arrival of the plants on to the scene to an ice age and subsequent mass extinction that occurred 35 million years later. Mosses change the chemical compositions of the rocks they grow and feed on, allowing them to interact and trap carbon dioxide from the atmosphere. Higher CO2 levels are important for trapping heat, and reduced levels are linked to periods of worldwide glaciation and ice age extinctions.
Until the new scientists announce that that's not true and they discover new facts and update the whole story.
Like usually.
That's interesting that they were covered in scales. I wonder how people figure this stuff out? That boggles my mind
Posted using Partiko Android
How people have found such plants and how scientists will research them, now they are very careful to know them.
Thanks for the sharing. Very interesting information.