ARE SPIDERS GETTING BIGGER?

AS SPIDERS GAME INDOORS THIS AUTUMN, SOCIAL MEDIA WAS CONVINCED THE UK'S ARACHNIDS HAD GROWN IN SIZE

- DR ADAM HART

John Keats might have described autumn as the “Season of mists and mellow fruitfulness” but for many arachnophobes it’s also the season of spiders. As evenings draw in, large spiders scuttling across the floor become a common sight. They are a reliable source of the ‘nature scare’ stories so beloved of the UK media, but are these spiders really getting bigger, as some reports claim?

The big spiders we often see in our homes are commonly called ‘house spiders’ but scientifically they belong to two genera, Tegenaria and Eratigena. There are several different species that are broadly similar and, when fully grown, pretty impressive. A couple of species can reach a leg span in excess of 10cm, which is more than big enough to give most people a scare.