Australasian Science: Australia's authority on science since 1938

Deselecting “Evolition”

By Simon Says

A report that whooping cough had evaded the current vaccine by mutating epitomises misconceptions about evolution.

Simon Grose is a Director of Science Media (sciencemedia.com.au).

The full text of this article can be purchased from Informit.

It was a straight little story on ABC-TV about a new strain of whooping cough that is resistant to the current vaccine. “The bacteria has mutated to evade it,” the reporter said, committing a subtle error that has become common usage in popular treatments of evolutionary development, from David Attenborough down.

Whether it be animations of trilobitesque critters crawling out of the surf onto a virgin beach, or re-enactments of early hominids stepping down from trees and walking upright into a grassy African plain, the language of their explanations implies that these evolutionary breakthroughs were provoked by some kind of willful urge or even aspirational intent. Evolution is presented as “evolition”.

Not so. Whenever a whooping cough bacterium infects a suitable new host it can proliferate into billions of individuals. The more clones that are produced, the more will be expressed by the host into spaces shared with other potential hosts. Thus the bacterial lineage can be sustained.

The more it is sustained the more cloning occurs, so mutations become more likely. The more mutations, the more likely it is for novel strains to arise. More novel strains means more chances for this bacterial lineage to continue as antagonists occur in its environment, as each strain has a different chance of resisting any antagonist.

So it is that a strain of...

The full text of this article can be purchased from Informit.