Arms Race

Life never stands still, and all living species are evolving over time. While evolutionary processes are usually pretty slow, one area where the pace of change picks up is between pathogens – namely viruses, bacteria and fungi – and the organisms they infect. It's like a genetic arms race with the host's immune system shifting and changing to fight off any infections, while the invaders becomes ever more clever at sneaking past its defences. These little red rods are Bacillus thuringiensis bacteria, busily infecting the body of a millimetre-long nematode worm and seen down a fluorescence microscope. By taking a closer look at the genes involved on both sides of this biological warfare, using worms and their attackers as a model system in the lab, researchers are starting to unpick the complex interactions between pathogens and their hosts as they evolve together, locked forever in their unending struggle.

Written by Kat Arney

Kat Arney

Writer

Dr Kat Arney is an award-winning science writer, broadcaster and public speaker, and is the founder and Creative Director of First Create The Media.

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• Image from work by Leila Masri and colleagues
• Christian-Albrechts-University of Kiel, Germany
• Originally published under a Creative Commons Licence (BY 4.0)
• Research published in PLOS Biology, June 2015