Spiders ‘sail on water like ships’

Spiders raise their legs to catch wind when traveling across water. They can control their speed using their silk as anchor to slow themselves down or stop moving across the water. The spiders were placed on water trays and the scientists observed the spiders’ behavior when air was generated through a pump.

In this way they “sailed” in turbulent, still, fresh and salt water conditions.

Sailors and travellers, including Charles Darwin aboard HMS Beagle, have often reported seeing “ballooning” spiders flutter from the air into the sails of their ships, far away from any shore. Under good wind conditions, a ballooning spider can travel up to 30 kilometers a day but it’s a fairly high-risk mode of locomotion.

The eight-legged critters use the wind to cross vast distances quickly, allowing them to claim new feeding grounds, find places to hide their egg sacks, or escape from inhospitable territory.

Meanwhile, the travelling strategies of spiders are always thought to be risky since they had little control over where they travelled. But later on, scientists found out that these arachnids can also survive and travel across bodies of water. Some can sail and some float through the wind through “ballooning” and not all spiders can do the fantastic feats mentioned; only certain spiders can. The animals did not show these behaviours on solid surfaces, suggesting that they are deliberate adaptations to water.

Their research could help explain why some types of spiders are present on almost every corner of the globe. They can sail by raising a pair of their legs to catch wind and let it propel them in a certain direction.

He told, “They even drop silk and stop on the water surface when they want”.

But until now, arachnologists believed that their conquest ended at water’s edge, that when they landed in a pond, a creek or the ocean, the spiders became helpless. Some pointed two forelegs up in a V-shape (see picture above), while others thrust their abdomen skyward – the equivalent of a handstand on the water. As surprising or absurd as it may sound, recent study in evolutionary biology shows that spiders have great sailing skill. It has led to some species spreading to new habitats like wildfire, making them part of most every ecosystem on land. This finding helps scientists answer the questions on spider migration and movements, explaining how they can move from one land mass to another and across such large distances.