Archaean
(Science: geology) The earliest period in geological period, extending up to the Lower silurian. It includes an azoic age, previous to the appearance of life, and an eozoic age, including the earliest forms of life.
this is equivalent to the formerly accepted term azoic, and to the eozoic of Dawson.
Dictionary > Archaean
You will also like...
![Chemical composition of the body](https://www.biologyonline.com/wp-content/uploads/2020/02/Chemical-composition-of-the-body-300x168.jpg)
Chemical Composition of the Body
The body is comprised of different elements with hydrogen, oxygen, carbon, and nitrogen as the major four. This tutorial..
![green plant cells](https://www.biologyonline.com/wp-content/uploads/2020/02/Plant-cells-vs.-Animal-cells-252x168.jpg)
Plant Cells vs. Animal Cells
Plant cells have plastids essential in photosynthesis. They also have an additional layer called cell wall on their cell..
![Human perception in action](https://www.biologyonline.com/wp-content/uploads/2020/02/Human-Perception-Neurology-252x168.jpg)
Human Perception – Neurology
This tutorial investigates perception as two people can interpret the same thing differently. Know more about human perc..
![Nephrolepis exaltata](https://www.biologyonline.com/wp-content/uploads/2020/02/Vascular-plants-ferns-and-relatives-252x168.jpg)
Vascular Plants: Ferns and Relatives
Ferns and their relatives are vascular plants, meaning they have xylem and phloem tissues. Because of the presence of va..
![Growth Patterns](https://www.biologyonline.com/wp-content/uploads/2020/02/Growth-Patterns-252x168.jpg)
Growth Patterns
This tutorial describes the sigmoid curve, annual plant growth, tree growth, human growth, and insect growth as the grow..
![Psychiatry and mental disorders](https://www.biologyonline.com/wp-content/uploads/2020/02/Psychiatry-Mental-Disorders-300x166.jpg)
Psychiatry & Mental Disorders
Different mental disorders are described here. Read this tutorial to get an overview of schizophrenia, affective mood di..