Cities make spiders bigger

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This is news that should delight all those, and there are many, to whom the mere prospect of crossing spiders causes cold sweats. According to the work of an Australian scientist, cities would make the charming beasts much bigger.

New Scientist tells how Elizabeth Lowe, from the University of Sydney, realized this unexpected impact of urbanization on spiders by studying more than 200 females of the species called Nephila, a priori harmless, adds the site. And the result is striking:

“Lowe explains that the spiders [from] the bush in Brisbane Water National Park, north of Sydney, have an average mass of 0.5 grams. But those from a city park near Bondi Beach weigh an average of 1.6 grams.”

A phenomenon that the scientist interprets as the consequence of the “urban heat island effect”, or in other words the fact that city centers are hotter than the surrounding areas due to the lack of vegetation and pavements, says the site IFLScience. Elizabeth Lowe adds that because of neon lights, which attract insects, spiders have more prey in the city center.

If her research is limited to the Australian perimeter, she envisages that the phenomenon is observable everywhere in the world and on other species of spiders, such as the dreaded redbacks, the most dangerous species in Australia.

However, arachnophobes should be reassured that we are not about to face a Z-series scenario with giant spiders devouring humans as guests. As we explained recently, these bugs (just like their little buddies worms, flies, etc.) can’t become monstrous either, due to a subtle hormonal combination. Phew!

Moreover, the New Scientist points out that excessive heat can be fatal to spiders. As Elizabeth Lowe explains:

“Last summer was very hot and most spiders died in Sydney.”

And if you need one last argument to convince yourself that spiders are not so much to fear, the scientist reminds you that they are actually very useful in cities, as they eat insects, feed birds and are usually harmless!