An Orb-weaver spider (Araneus diadematus) in Rennes, western France (Photo: Damien Meyer/ AFP/Getty Images)
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City living is making spiders bigger, study finds

According to new research, city-dwelling spiders are larger and more fertile than their rural-dwelling relatives.

The growth of cities destroys the homes of many animals. With habitats drenched in cement, their only option is to relocate - and in the worst cases, urban expansion can cause species extinction. However, it’s not all doom and gloom for some species, as city living appears to bring out the best in them. Have you noticed that spiders are looking meatier nowadays?

According to new research, city-dwelling spiders are flourishing. Similar to rats and pigeons, spiders are “urban exploiters”. This means that they thrive in urban surroundings. Despite our squeamish attitudes towards them, spiders are important creatures: they greatly impact food webs, plant colonies and herbivore abundance, and they help to control the insect populace.

Most research on the expansion of cities focuses on birds. For instance, noise pollution has forced birds to change their calls, while other studies show that some birds have even stopped migrating. Researchers from the University of Sydney, however, were interested in the changes in spider anatomy that might have come from living in cities, and specifically Golden Orb-Weaving (Nephilla Plumipes) spiders, which are common in both urbanised and rural Australian landscapes. They build strong semi-permanent webs with golden-looking silk, and, once matured, they reside in this web their entire life. Thus, their “coach potato” lifestyle makes them ideal research subjects.

The researchers collected 222 spiders from rural and urbanised areas. All spiders were female and had reached maturity, and their body size, fat reserves, and ovary weight were recorded. The findings showed that rural-dwelling spiders had smaller bodies, but that city-dwelling spiders were larger, and more fertile. Places with roads, buildings and a lack of greenery typically denoted larger spiders. The researchers proposed that temperature differences could explain these results, as cities are much warmer than rural areas thanks to the urban heat island effect.

Their results could also reflect differences in prey availability. The study's lead author, ecologist Elizabeth Lowe, explained in more detail:

There were strong associations in particular between spider size and the presence of hard surfaces (such as roads and buildings) and lack of vegetation. These hard surfaces contribute to the urban “heat island” effect, which makes it warmer in cities than surrounding areas. It is also likely that there is more food for the spiders in the city as a result of night lighting and increased resources. This combination of warm temperatures and more food would allow spiders to put more energy towards growth and reproduction. Fewer predators and parasites in urban areas could also allow urban spiders to grow larger.”

This study is only applicable to one species of spider in one Australian city, so it's not fair yet to say that all urban spiders are getting bigger - so don't panic about huge spiders with larger ovaries just yet. However, the researchers pledge that this is promising news:

The fact that some spiders benefit from urbanisation is a good thing. In order to maintain biodiversity in cities, we need to be able to support diverse populations of spiders and other invertebrates” Lowe said. “By gaining a better understanding of the impacts of urbanisation on wildlife in cities, we can work towards creating healthy, functioning ecosystems in urban areas." 

Photo: Getty
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Brexit Big Brother is watching: how media moguls control the news

I know the Daily Mail and the Daily Telegraph well, and I don’t care to see them like this.

It would take a heart of stone now not to laugh at an illustration of Theresa May staring defiantly out at Europe from the British coast, next to the headline “Steel of the new Iron Lady”.

Those are, however, the words that adorned the front page of the Daily Mail just five months ago, without even a hint of sarcasm. There has been so much written about the Prime Minister and the strength of her character – not least during the election campaign – and yet that front page now seems toe-curlingly embarrassing.

Reality has a nasty habit of making its presence felt when news is remorselessly selected, day in and day out, to fit preconceived points of view. May and her whole “hard Brexit” agenda – which the public has now demonstrated it feels, at best, only half-heartedly enthusiastic about – has been an obsession of several British newspapers, not least the Daily Mail and the Daily Telegraph.

I know these papers well, having spent the best part of a quarter-century working for them, and I don’t care to see them like this. When I worked there, a degree of independent thought was permitted on both titles. I joined the Telegraph in 2002; at the time, my colleagues spoke with pride of the paper’s tolerance to opposing views. And when I was at the Mail, it happily employed the former Labour MP Roy Hattersley.

Would I be able to run positive stories about, say, my mate Gina Miller – who successfully campaigned for parliamentary scrutiny of the Brexit process – in the Telegraph if I were there today? Or at the Daily Mail? Dream on: it’s two minutes of hate for that “enemy of the people”.

Morale in these newsrooms must be low. I am finding that I have to allow an extra half-hour (and sometimes an extra bottle) for lunches with former colleagues these days, because they always feel the need to explain that they’re not Brexiteers themselves.

Among the Telegraph characters I kept in touch with was Sir David Barclay, who co-owns the paper with his brother, Sir Frederick. Alas, the invitations to tea at the Ritz (and the WhatsApp messages) came to an abrupt halt because of you-know-what.

I don’t think Sir David was a bad man, but he got a Brexit bee in his bonnet. I was conscious that he was close to Paul Dacre, the editor of the Daily Mail, and both had cordial relations with Rupert Murdoch. It became clear that they had all persuaded themselves (and perhaps each other) that Brexit suited their best interests – and they are all stubborn.

It seems to me unutterably sad that they didn’t sound out more of their factory-floor staff on this issue. We journalists have never been the most popular people but, by and large, we all started out wanting to make the world a better place. We certainly didn’t plan to make it worse.

People used to tell me that papers such as the Daily Mail and the Telegraph changed because the country had but, even in the darkest days, I didn’t agree with that premise. We are in the mess we’re in now because of personalities – in newspapers every bit as much as in politics. The wrong people in the wrong jobs, at the wrong time.

Would the Daily Mail have backed Brexit under Dacre’s predecessor David English? It is hard to imagine. He was a committed and outward-looking Europhile who, in the 1970s, campaigned for the country to join the EU.

I can think of many Telegraph editors who would have baulked at urging their readers to vote Leave, not least Bill Deedes. Although he had his Eurosceptic moments, a man as well travelled, compassionate and loyal to successive Conservative prime ministers would never have come out in favour of Brexit.

It says a great deal about the times in which we live that the Daily Mirror is just about the only paper that will print my stuff these days. I had a lot of fun writing an election diary for it called “The Heckler”. Morale is high there precisely because the paper’s journalists are allowed to do what is right by their readers and, just as importantly, to be themselves.

Funnily enough, it reminded me of the Telegraph, back in the good old days. 

This article first appeared in the 22 June 2017 issue of the New Statesman, The zombie PM

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