- Current section: Introduction
- Learning outcomes
- 1 The Cambrian explosion
- 2 The Ordovician seas
- 3 The Silurian Period and the invasion of the land
- 4 Life in the Silurian sea
- 5 The Devonian Period
- 6 Vertebrates move onto land
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Life in the Palaeozoic
Fossils are a glimpse into the distant past and fascinate young and old alike. This...
Fossils are a glimpse into the distant past and fascinate young and old alike. This unit will introduce you to the explosion of evolution that took place during the Palaeozoic era. You will look at the many different types of creatures that existed at that time and how they managed to evolve to exist on land.
After studying this unit you should be able to:
- describe some key events in the evolution of life during the Palaeozoic Era, such as the first appearance of major groups of invertebrates and vertebrates, and the invasion of the land;
- identify some common types of fossil organisms that were living in Palaeozoic seas, and comment on their likely environment and geological age;
- make inferences from fossils about the biology and mode of life of some Palaeozoic organisms.
Life in the Palaeozoic
The Palaeozoic Era was a very important time in the history of life. Using evidence from fossils, we start by looking at the Cambrian explosion, when many forms of animal life first appeared about 545 million years ago. Then we move on to study creatures living in the Ordovician seas, including the extinct trilobites. Next, we'll investigate the invasion of land by plants and invertebrates that occurred in the Silurian Period, and look at life in Silurian seas. You'll also learn about the Devonian Period, when vertebrates first moved onto land. The unit finishes with a brief outline of vertebrate evolution.
This unit is from our archive and is an adapted extract from Fossils and the history of life (S193) which is no longer taught by The Open University. If you want to study formally with us, you may wish to explore other courses we offer in.
This is an extract from an Open University course which is no longer available to new students. If you found this interesting you could explore more free Natural History course units or view the range of currently available OU Natural History courses.