Spiders grow larger in urban areas


Since 2008, according to UN figures, more people live in cities than the country. And despite the romanticism of a rural life, humans thrive in them – they live longer, healthier lives (at least in developed countries).

Some argue that cities actually reduce human stress on the environment.

Spiders seem to share this view. New research shows that at least some of them grow larger and carry more eggs when they live in more urbanised areas.

The scientists from University of Sydney studied orb-weaving spiders in sites of varying degrees of urbanisation around in Sydney and investigated changes in the their body size, fat reserves, and ovary weight.

Spiders were smaller in areas with more vegetation and larger in more developed areas.

The paper, published in PLOS ONEsuggested a few possible reasons for this. Hard surfaces such s roads and concrete walls retain more heat, so the spiders spend less energy keeping warm, helping them grow.

The city-slicker spiders might also have more to eat as they congregate around light posts that attract a smorgasbord of beetles, flies and moths.