A few days ago, I was conducting a training programme for local youth near Dehradun. The programme was on butterflies and moths, which are part of the world of insects. In all my training programmes, I love to quiz the participants. I put up images of a host of creatures such as butterflies, moths, bees, spiders, wasps, mites, dragonflies, damselflies, ticks and harvestmen on the screen and ask them to pick the odd ones out. Can you tell me which of these creatures are not insects?
If you have not guessed already, spiders, mites, ticks and harvestmen are not insects but are arachnids. Arachnids are eight-legged creatures unlike insects, which have six legs. The word arachnid is derived from the Greek word aráchne that means ‘spider’. Most people are aware of spiders, ticks and mites, but a harvestman is an unfamiliar creature for many people.
Have you ever seen a spider whose head and body seem fused into one? If so, you have spotted a harvestman. While most harvestmen are nocturnal, a few of them are diurnal, too. During our trip to Pakke Kessang in Arunachal Pradesh, we spotted a lovely yellow-spotted black harvestmen posing on a green leaf for us. Harvestmen can be seen everywhere – in cities and villages alike – and they occupy varied habitats.
Harvestmen have really long legs, and hence many people refer to them as ‘daddy longlegs’. This is also a name used for certain spiders, so make sure that you don’t confuse the two. Most harvestmen have very tiny eyes that cannot form images, hence they use their second pair of legs as antennae to check out prey. Most harvestmen are omnivores and eat small insects as well as fungi and other plant material. They ambush very small insects and eat them. While harvestmen look dainty and fragile, they have many tricks up their sleeves to protect themselves. When attacked by a predator, a harvestman can break off one of its legs, which will continue to twitch and distract the predator, while the harvestman escapes. Sometimes the harvestman will play dead if attacked. Many harvestmen display a bobbing kind of motion, vibrating to make themselves less visible to predators. Some harvestmen emit a foul smell to deter predators. On occasion, a large group of harvestmen congregate at one spot. Safety in numbers, they believe. Actually, a whole bunch of vibrating or stinking harvestmen can deter the most ferocious of predators! I recall seeing hundreds of harvestmen in a tree hollow, and when I approached them; they began to vibrate together, leaving me mesmerised!
Go green
Did you like my last article on the snail-eating snake? Every year, July 16 is celebrated as World Snake Day. On this day, passionate snake lovers attempt to dispel the fear of snakes that most people have, and stress the need to conserve and save these marvellous creatures.
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