If you think of spiders as feasting only on insects or small animals, you may be surprised to learn that a large number of spiders actually have a diverse diet and nibble on plant material in addition to their usual carnivorous menu.
Zoologists from Switzerland, the United Kingdom and the United States found examples in literature of spiders enjoying plant-based snacks. They found that more than 60 species of spiders in 10 families have been documented feeding on nectar, sap, honeydew, seeds, and bits of vegetation from trees, shrubs, grasses, orchids and even carnivorous plants.
CNET writes, "The biggest group that likes a veggie meal once in a while is Salticidae, a family of jumping spiders with over 5,000 species spread across the entire world, characterised by the pair of big, shiny eyes at the front of their heads. Salticidae accounted for 60 percent of the documented plant-eating incidents."
The ability to eat plants is likely an adaptation to help spiders stay alive when animal or insect prey is hard to find, and also may help provide them with nutrients they can't get in a strictly carnivorous diet. The researchers note, however, that science still doesn't know exactly how plants help spiders' nutrition or how it affects their behavior. It would be a fascinating area of study for anyone interested in arachnids in the garden.
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