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Crab Spiders Catch Their Bee Prey By Making Flowers Appear More Attractive

Crab Spiders Catch Their Bee Prey By Making Flowers Appear More Attractive

There are plenty of things that can hinder a bee’s ability to pollinate flowers, but most of you would probably not suspect a type of spider to get in the way of a bee’s pollination duties. After all, spiders crawl on the ground, and they cannot fly. Based on this basic knowledge of spider behavior, it seems fair to assume that bees are safe from spider attacks while they are pollinating flowers. However, the world is rich in a multitude of different arthropod species, and spiders that prey on bees during pollination do exist. The crab spider, also known as a flower spider, is a bizarre looking spider specimen. These spiders are common in Australia and many other regions, including parts of Europe. These spiders have smooth and glossy bodies, and most species do not grow to be any larger than a centimeter in length. European and Australian varieties of crab spider are known for being remarkably colorful. This colorful exterior comes in handy when crab spiders camouflage themselves within a flower’s vibrant petals. Crab spiders are often found nestled within the petals of certain flowers for two reasons. One reason is to camouflage themselves from predators like birds. The second reason also involves camouflage, but in this case the spiders are waiting to ambush an unsuspecting and tasty pollinating insect. This method of preying on honey bees is quite effective, as the spiders are able to alter a flower’s colors in order to make them appear more attractive to pollinating bees.

Unlike humans, bees can perceive colors that are expressed through ultraviolet light. Bees choose which flowers to pollinate based on the attractiveness of a particular flower’s UV color scheme. Researchers have determined that crab spiders are able to use their own natural colors in order to make flowers appear more attractive to bees. Crab spiders will climb into a flower’s petals and sit in waiting for an unsuspecting honey bee to come and pollinate the occupied flower. Unfortunately for honey bees, the most desirable flowers are the ones that contain predatory crab spiders. Upon a bee’s descent onto a particular flower, a crab spider will emerge in order to snatch the honey bee from the air. Honey bees also use olfactory senses when choosing flowers for pollination, but when researchers inhibited the odors emitted by flowers, the honey bees still chose flowers that contained crab spiders. This finding clearly indicates that crab spiders have adapted an ability to catch honey bee prey by manipulating the way a flower’s color is perceived by honey bees. The shiny and richly colored exterior of crab spiders likely evolved for this reason.

Have you ever heard of any other type of spider species that preys on flying insects?