By Dr Anne Wignall, Institute of Natural and Mathematical Sciences, Massey University.
Spiders often get a bad reputation – with eight legs, fangs and a habit of coming into our homes without invitation, they can seem like they belong in another world. But spiders are fascinating and can be more like us than we think.
One of the more common types of spiders that we are likely to see around our backyards, and inside our houses, are jumping spiders. As their name implies, jumping spiders can jump! Jumping spiders also have excellent vision that is often compared to that of a cat. They are easily recognized by the presence of two particularly large eyes in the middle of their heads, surrounded by six smaller eyes. Their vision is used to hone in on prey. Flies, bugs and other spiders are common targets but some species of jumping spider even specialise on mosquitoes, or ants. Their fierce hunting ability means they’re perfect houseguests if you don’t want too many other invertebrates around!
They also look amazing. Many male jumping spiders have evolved a huge array of colours and body patterns to impress females, as well as some snappy dance moves during courtship. Male courtship dances often involve both visual and vibratory components. Visual components can include leg waving and the male zigzagging from side to side as he approaches the female. In order to generate vibrations, the males tap their legs, or pedipalps, on the substrate or waggle their abdomens in order to impress females with their stamina, strength or rhythm.
Perhaps one of the most interesting aspects of jumping spiders, however, is their brain power. Despite having very small brains, these spiders display all sorts of behaviours that we usually associate only with humans. For example, jumping spiders can solve problems. When presented with a prey item, with no direct routes available to reach the prey, they can figure out appropriate detours in order to reach the food – even when those detours meant losing sight of the prey. This means that they can remember their goal, and the way to reach it, even when it is no longer in front of them.
It’s these astounding abilities that are part of the reason I became a scientist. I am a behavioural ecologist and study how and why animals look and behave the way that they do. Invertebrates like these jumping spiders have an intriguing array of complex behaviours that make them ideal research subjects.
So look past spiders’ small size and strange appearance and you’ll see that amazing things really do come in small packages.
Dr Anne Wignall is a behavioural ecologist in the Institute of Natural and Mathematical Sciences at Massey University. She uses invertebrate model systems, particularly spiders and insects, to answer evolutionary questions. She is particularly interested in the interactions between ecology and behaviour.
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