Vital Variety

We are a mashup of our parents. Their genetic material mixes together to form the unique DNA combinations in each of us that produce the rich variety of human life. In contrast, bacteria – microscopic beings found in every nook of our planet – typically reproduce simply by dividing, meaning that successive individuals are all identical clones. We didn’t know of any way for bacteria to swap genetic information, until Joshua Lederberg (pictured, right) – born on this day in 1925 – found them exchanging little DNA loops (plasmids) along temporary connecting bridges in 1946. A few years later he showed they can also share genes without even touching, via a virus courier (bacteriophage). These mechanisms became core tools in the fledgling field of molecular biology, and the discoveries won Lederberg a share of the 1958 Nobel Prize. Appreciating the value of variety, he went on to pioneer the study of artificial intelligence and biology in outer space.

Written by Anthony Lewis

Anthony Lewis

Writer

Ant was the web editor in the early days of BPoD, and has since worked with the UK’s top science organisations as a writer and multimedia producer. He now splits his time between freelance work and managing multimedia at The Lancet.

Website

• Image from Stanford Medical History on Flickr
• Image originally published under a Creative Commons Licence (CC BY-NC-SA 2.0)