photo of noble chemistry medal

But it’s only a theory

The theory of evolution shows how science operates

There is an idealised view of the way science works. It starts with an observation and a question (our hypothesis). For example: When we make a loud noise spiders jump in the air, so do they hear through their legs?

Next we need to test the hypothesis with an experiment. If we cut off their legs, they no longer jump in response to noises. We triumphantly conclude that spiders do indeed hear through their legs and prepare our Nobel speech.

But it is possible that we may have overlooked something. Our conclusions are provisional. All current observations may be consistent with the theory, but more experiments might force us to change our thinking. Perhaps a bright spark points out that legless spiders wouldn’t be able to jump even if they had heard a noise...

How has the theory of evolution stood up to scrutiny? Pretty well. It remains the best explanation for how life on Earth has been shaped. Appropriately enough, it continues to evolve as new discoveries are made. It’s theoretically possible that some new discovery will contradict it, but that hasn’t happened yet.

Lead image:

Adam Baker/Flickr CC BY NC

About this resource

This resource was first published in ‘Evolution’ in January 2007 and reviewed and updated in December 2014.

Ecology and environment, History
Education levels:
16–19, Continuing professional development