More Than 3800 million years ago (mya) as Earth cooled, liquid water prouced oceans in which small single-celled organisms evolved.
Many believe that this marked the first ever signs of life. These early beginnings are called "prehistory", because they happened before recorded history.
Much of our evidence of early life coes from fossils. Using this evidence, palaeontologists divided Earth's prehistory into time spans called eras, and eras into periods.
Paleozonic era
In the early part of the Cambrian (570 to 510 mya), Life was mostly confined to the tree-ferns, and club mosses such as Lepidodendron. By the Permian period(290 to 245 mya) , much of the land was covered by desert.
In the beginning
Fossil prokaryotes (simple single cells) have been found in 3,400- to 3,300- million-year-old rocks in Australia and South Africa. Some of these such as the blue -green bacteria,formed strings of cells and produced layered mounds called stromatolites.
First Plants
Until the end of the Silurian period (439 to 408 mya), most plants lived in water The oldest known plant. cooksonia, developed a rigid stem for carring water from roots, allowing it to thrive on land
Invasion of the Land
As plants moved on to land, invertebrate animals followed, oxygen levels and drier conditions. The first were the arthropods.Some, such as Acantherpestes,probably survived the same way millipedes do today. by feeding on decomposing plants. Amphibians and reptiles followed the arthropods.
Early birds
Birds with feathers developed early in the evolution of which they are closely related. Early birds, bird Archaropteryr, may have used their feathers for insulation or display, as well as flight.
continue my next post...........
Many believe that this marked the first ever signs of life. These early beginnings are called "prehistory", because they happened before recorded history.
Much of our evidence of early life coes from fossils. Using this evidence, palaeontologists divided Earth's prehistory into time spans called eras, and eras into periods.
Paleozonic era
In the early part of the Cambrian (570 to 510 mya), Life was mostly confined to the tree-ferns, and club mosses such as Lepidodendron. By the Permian period(290 to 245 mya) , much of the land was covered by desert.
In the beginning
Fossil prokaryotes (simple single cells) have been found in 3,400- to 3,300- million-year-old rocks in Australia and South Africa. Some of these such as the blue -green bacteria,formed strings of cells and produced layered mounds called stromatolites.
First Plants
Until the end of the Silurian period (439 to 408 mya), most plants lived in water The oldest known plant. cooksonia, developed a rigid stem for carring water from roots, allowing it to thrive on land
Invasion of the Land
As plants moved on to land, invertebrate animals followed, oxygen levels and drier conditions. The first were the arthropods.Some, such as Acantherpestes,probably survived the same way millipedes do today. by feeding on decomposing plants. Amphibians and reptiles followed the arthropods.
Early birds
Birds with feathers developed early in the evolution of which they are closely related. Early birds, bird Archaropteryr, may have used their feathers for insulation or display, as well as flight.
continue my next post...........
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