Archaea and the Tree of Life

As part of the latest issue of Microbiology Today, called ‘What is life?’ (published online 10 May 2016), we explore the Archaea. These are microbes that have been around since the beginnings of life on Earth but were only discovered in the last 40 years.

Content copied from a blog published by the Microbiology Society in May 2016.

Every living thing on this planet belongs to one of three branches on the tree of life. Bacteria make up one branch, while animals, plants and fungi together make up another.

But the third domain of life wasn’t even discovered until the 1970s. This mysterious group of organisms, the Archaea, remain one of the biggest puzzles in microbiology. Although superficially they look similar to bacteria, in evolutionary terms they couldn’t be more different.

Archaea have been discovered in some of the most hostile environments on the planet, in conditions that would kill other forms of life. Even more strangely, we have yet to find a single species of Archaea that causes disease.

Dr Thorsten Allers from the University of Nottingham explores how these fascinating micro-organisms were first discovered – and how they have even made us reconsider our own place on the tree of life.

You can read more about Archaea and the meaning of life in the latest issue of Microbiology Today: What is Life? (published online 10 May)