About 700 Mio years ago,
higher plants and animals with soft bodies diversify rapidly. The glacial
period at 580 Million years is followed by the rapid appearance of all basic
designs for animal life, including hard shells and skeletons. This period is
dubbed the “Cambrian Explosion”, and rings in the Phanerozoic Eon, or “the age
of visible life”.
The Palaeozoic Era includes
300 million years of relatively warm climate.
A brief glacial period is
documented in Saharan sediments (then located around the Southpole) at the
transition between Ordovician and Silurian period.
The coldest period in the
history of the planet began in the Carboniferous period at about 330 million
years, and ended at about 250 million years. In this epoch, the supercontinent
Pangaea was formed. This huge continental land mass covered much of the
southern hemisphere, and was covered with ice.
The fossil record seems to
indicate a series of unfortunate cataclysmic events. These events may include
huge volcanic eruptions, cosmic collisions, climate changes, solar
fluctuations, and other. There are indications of at least five major mass extinctions, including the Late Ordovician (440
mio) and Late Devonian (365 mio).
Over the last 600 Mio years,
99.9% of all species that ever existed have vanished. However, since biological
diversity has increased there are currently 1 million different species, three
quarters of them insects.