There were a few extinctions over this period due to the changing climate but plants adapted to the various climates that emerged after the glaciers retreated.

66 million years ago – 0 million years ago

0 million years ago

66 million years ago

Cenozoic

• Paleocene Epoch: 66-56 million years ago.
• Eocene Epoch: 56-34 million years ago.
• Oligocene Epoch: 34-23 million years ago.
• Miocene Epoch: 23-5 million years ago.
• Pliocene Epoch: 5-2.6 million years ago.
• Pleistocene Epoch: 2.6 million to 10,000 years ago.

Now, the Cenozoic Era (66 Million Years Ago to Present) is a story about us. It’s the era when humans began to evolve. And this finally happened with the Cretaceous-Paleogene extinction event at the start of the Cenozoic Era. From there, early humans evolved from small, furry mammals.

(Image credit: Public domain.) The Cenozoic era, which began about 65 million years ago and continues into the present, is the third documented era in the history of Earth. The current locations of the continents and their modern-day inhabitants, including humans, can be traced to this period.

251.902 (+/- 0.024) million years ago

4,000 million years ago

541 (+/- 0.4) million years ago – 251.902 (+/- 0.024) million years ago

We can follow the development of life in detail during the Paleozoic, because at the beginning of that Era, life forms developed hard parts like shells, teeth, bones, and woody parts that were easily preserved as fossils. Earlier life forms were single-celled and soft-bodied, so older rocks contain few fossils.

The extinction that occurred 65 million years ago wiped out some 50 percent of plants and animals. The event is so striking that it signals a major turning point in Earth’s history, marking the end of the geologic period known as the Cretaceous and the beginning of the Tertiary period.

Just as the first complex animals were settling into Earth’s oceans, oxygen levels fell dramatically and wiped many of them out.

In the early Cambrian, Earth was generally cold but was gradually warming as the glaciers of the late Proterozoic Eon receded. The middle of the Cambrian Period began with an extinction event. Many of the reef-building organisms died out, as well as the most primitive trilobites.

The Cambrian period, part of the Paleozoic era, produced the most intense burst of evolution ever known. The Cambrian Explosion saw an incredible diversity of life emerge, including many major animal groups alive today. Among them were the chordates, to which vertebrates (animals with backbones) such as humans belong.

The plants of the Cambrian were mostly simple, one-celled algae. The single cells often grew together to form large colonies. The colonies looked like one large plant.

The Cambrian explosion or Cambrian radiation was an event approximately 541 million years ago in the Cambrian period when practically all major animal phyla started appearing in the fossil record. It lasted for about 13 – 25 million years and resulted in the divergence of most modern metazoan phyla.

Anomalocaris lived in North America, Asia, and Australia during the Late Cambrian Era, from 535 – 520 million years ago.

The Cambrian Period marks an important point in the history of life on Earth; it is the time when most of the major groups of animals first appear in the fossil record. This event is sometimes called the “Cambrian Explosion,” because of the relatively short time over which this diversity of forms appears.

The Cambrian explosion, considered a crucial event in the evolution of animals, was in full burst by 518 million years ago. ‘It’s when most of the few dozen major animal body plans first appear in the fossil record and diversify,’ explains Greg. ‘But it is actually more than that.

the dinosaurs were killed. The mass extinction that occurred on earth 65 million years ago was immediat… The mass extinction at the end of the Ordovician period was probably caused … Findings from layers dating to the Cambrian geological period show an appear…

These clusters of specialized, cooperating cells eventually became the first animals, which DNA evidence suggests evolved around 800 million years ago. Sponges were among the earliest animals.

Whatever their origins, animals may have ventured onto land early in the Cambrian. Previously scientists believed that animals did not begin to colonise the land until the Silurian (440 – 410 million years ago).