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." 

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Shell-shock symphony: Berg’s Wozzeck – opera’s take on post-traumatic stress disorder

Begun in 1914 and premiered in 1925, Wozzeck has class struggle, poverty and mental health problems as its principal subjects.

When I was 12 years old, I made a devastating discovery. The arias from my favourite operas – Rigoletto, Turandot, The Barber of Seville – which I played over and over again, winding and rewinding the cassettes ­until they ceased to work, did not ­necessarily have words that matched the beauty of the music. Intense study of a book I had received for Christmas called Stories from Opera taught me that although some of the soaring melodies I adored carried words about love, death, horror and tragedy, other lyrics, in translation, proved to be people agreeing where to meet later, or misremembering each other’s names.

This crushing disappointment came to mind again recently while I was listening to an edition of Radio 3’s Building a Library, a segment of its regular Saturday-morning CD review, in which new releases are compared and contrasted with archive recordings to find the best listening experience. The reviewer Gillian Moore was surveying the available recordings of Alban Berg’s Wozzeck. She gave credit to several English-language recordings for the clarity they offer newcomers to this work, but eventually concluded that she must recommend a version using the original German, because there were crucial aural elements that could not be reproduced without it.

Moore, now director of music at the Southbank Centre, chose to kick off a series of semi-staged concert performances of operas with Wozzeck. Although undoubtedly an opera, it was a far cry from the fairy stories and doomed romances that filled my pre-teen ears, but it worked surprisingly well stripped of scenery, costumes and other theatrical accoutrements.

Zurich Opera’s presentation placed importance on the orchestral score above all else, allowing its jagged and insistent lines to remind us that this is music born of the dark years between the world wars. Begun in 1914, but delayed while Berg served in the Austro-Hungarian army (it premiered in 1925), it has class struggle, poverty and mental health problems as its principal subjects. The score owes much to Berg’s fellow Viennese composers Gustav Mahler and Arnold Schoenberg (Mahler’s widow put up the money for the initial publication of the score). At times in this production, the orchestra was so utterly central that it felt like a symphony with singing, rather than vocal melodies with accompaniment.

The Wozzeck of the title is a poor soldier, flawed and dogged by madness and visions we would probably now see as signs of post-traumatic stress disorder. He scrapes a living for his girlfriend, Marie, and their son by humiliating himself before his military and class superiors (the Captain, the Doctor, the Drum Major) and by participating in degrading medical “experiments”. The star of the show, the German baritone Christian Gerhaher, had to withdraw at the last minute for health reasons, so the British singer Leigh Melrose stepped in to reprise his Wozzeck from the widely acclaimed 2013 ENO production. Despite performing from behind a music stand, Melrose acquitted himself well, handling the transitions between Berg’s three singing styles: “half-singing”, Sprechgesang (or “spoken singing”) and full vocalisation to great effect.

Gun-Brit Barkmin, with a severe Twenties bob and a flowing scarlet dress, was a superb Marie – alternately harsh and soft as the music demanded it, flirting destructively with the Drum Major while conveying how little choice she had in the matter. Of the ensemble, Lars Woldt’s Doctor particularly stood out, using the German libretto to drag every ounce of black comedy out of his character’s fascination with Wozzeck’s bodily functions. The high vocal standard proved Moore’s point about the necessity of the original German libretto – it is a difficult language to sing, because of all the harsh consonants and modified vowels, but when used expertly can be unendingly expressive. We hear this in the way the double “zz” of the title character’s name becomes a derisory bitten-off “tz” in the mouth of the Captain; and Wozzeck’s exclamation in Act I that “Du, der Platz ist verflucht!” sounds so much more accursed and deranged with all those consonants in such close proximity.

The German sociologist Theodor Adorno once called Berg “the foreign minister of the land of his dreams”, much to the composer’s amusement; but, hearing the score for Wozzeck laid so bare, you understand what Adorno meant. The incredible double crescendo on a single B from the orchestra after Wozzeck murders Marie – raised by the conductor Fabio Luisi in this performance to an unbearable volume before being allowed to die away – feels like music from an other-worldly nightmare. Yet, for the war-battered men who inspired Wozzeck, his tragic half-life was all too real.

Caroline Crampton is web editor of the New Statesman.

This article first appeared in the 08 October 2015 issue of the New Statesman, Putin vs Isis