World’s biggest and most awesome spiderwebs, one spans accross a river

Libero.id - This article is definitely not for those who suffer from arachnophobia. But if you don’t, you are lucky to see how complex and beautiful the silky webs that spiders weave.

Spider webs come in various shapes and sizes to catch their preys. Different spiders spin webs in the shape of funnels, sheets, tubes, or complicated tangle of lines similar to that of protecting laser maze in sci-fi mystery series.

Despite the diversity, if asked to draw a spider web, most of us would instantly think of the classic orb web.

The orb web is the one with a spiraling circular pattern of interconnecting threads; the ones we usually encounter, as a lot of spiders spin this type of web. That includes most of the nearly 3000 members of the Araneidae family, commonly known as the orb weavers and the third largest spider family on Earth.

Talking about world’s biggest spider webs ever, there are a few names to mention:

1. The European garden cross spider

Photo: garden cross spider/Stephen Dalton-NPL

This Araneidae belongs in the northern hemisphere, and is named for the white cross marking on its ball-shaped abdomen. Its flashy silken webs can reach over 40 centimeters in diameter, and are built to catch common garden insects like flies, wasps and butterflies.

Photo: garden cross spider/wikimediacommons

The webs are particularly seen in the autumn, when lush foliage of summer turns into golden yellow and brown.

2. Nephila spiders

In Earth’s warmer regions, both spiders and their webs can be bigger. Spiders from genus Nephila spin webs with golden hints in the constructing silk, named the golden orbs, which are the largest webs in Australia. These webs can reach up to one meter in diameter and hang between trees or sign posts.

Photo: golden orb spider/David Noton-NPL

The spiders themselves can grow as big as human hand’s palm, with legs included. Their webs are strong enough to entangle birds, which are one of the spider’s prey.

The largest golden orb weaver hit the headlines back in 2009. It was a female Nephila komaci, a spider with a 4 centimeters long body, with over 10 centimeters legs. Its giant golden orb webs can reach more than one meter in diameter.

Photo: golden orb spider/fineartamerica

3. Darwin's bark spider

Though scientists have found the giant spider webs span over one meters, one species spins more extraordinary webs than any other. This gigantic web, which is almost monumental, spans accross a river and is constructed from silk tougher than Kevlar[1].

Photo: darwin bark spider accross the river/Matja Gregori

Photo: darwin bark spider accross the river/wikipedia

This web had been found only in Madagascar in 2010. The responsible species was officially described on the 150th anniversary of the publication of Charles Darwin's On the Origin of Species which set the precedent for its name.

It’s hard to believe how nobody noticed these spiders’ existence before; a single majestic web can span over 25 meters wide, crossing a river just like giant silky bridge.

To build this colossal prey trap, a female spider sprays an endless line of silk from one bank of the river to the other. Air currents carry it across to the other side to create a bridge. From the center of this silky bridge, the spider starts to construct a spiraling orb web that can reach nearly 3 meters in diameter.

You might expect this enormous web belongs to a fictional giant; maybe Shelob from The Lord of The Rings, or Aragog from Harry Potter? Sorry to let you down, but this Darwin's bark spider is neither Shelob nor Aragog.

Photo: darwin bark spider Caerostris darwini/Matja Gregori

"Caerostris darwini (the Darwin's bark spider) females measure about 1.5 centimeters in body size, and weigh about 0.5 gram, while males are much smaller, weighing 10 times less," says Matjaž Gregorič of the Slovenian Academy of Sciences and Arts in Ljubljana, who has been researching the spiders since their discovery.

Photo: darwin bark spider camouflage as barks/Matja Gregori

These small spiders are also camouflaged to match tree bark.

Then why and how would such small spiders produce the huge quantites of silk needed fot their gigantic webs?

"Why their webs are so big is a good question and we don't have a definite answer yet," says Gregorič.

While he and his scientists team were seeking and answer, they found that the genus Caerostris seems to have tougher silk than any other spider. While Nephila spiders spin webs with dense patterns of lower quality silk, Caerostris weave sparse webs with very tough silk. Both spinning style provide decent strength to catch prey.

But by positioning their webs above rivers, Darwin's bark spiders may capture dozens of dragonflies, mayflies and other energy-rich insects that buzz over the water.

The scientists also have found that the silk is stronger than steel. It has also been mentioned as the toughest biomaterial known.

Toughness and strength may sound similar, but there is a difference between the two words. Strong materials are resistant to stress, but tough materials are highly flexible, meaning they can absorb more energy before breaking. This is essential in a spider's web, as each strand has to resist the impact and thrashing movements of prey without disturbing the rest of the structure.

With a combination of strength and toughness that is highly sought after by engineers to make new materials, scientists have set their intentions on creating a future materials from spider silk. There is no need to look further than the Darwin’s bark spider.