Another German phrase says “Immer der Nase nach“, meaning just go straight (where the nose points). But it is also used to say follow your scent to find what you are looking for (e.g. the washroom).
So how do crab spiders follow their noses? I’m not sure if they do, but somehow it could be…
Crab spiders can be found in flowers, where they wait for insects. With widely spread legs they would catch insects that came to slurp some nectar. They don’t build webs, but they also do not hunt actively. They just sit and wait, and I would say a flower is a good place to wait for bees and all those. Somehow they must have found out what honeybees like (nectar) and so just wait there. Depending on the flowers color, the spiders are white or yellow, so that they are not easy to find.
A team of researchers from Austria and Australia (state gendered: Austr(al)ia?!) wanted to find out how they choose the flower. Wouldn’t make sense to sit in a flower that no one likes, right? Options were: size, color or odor of the flower. Size and color would make sense, you want to have a comfortable place to eat, and maybe changing color is nothing you want to do every day? But do they smell?
The result of that study was, that bee and spider prefer the same flowers! That is only try when the odor o the flower was present. When a film covered the flower, so that you can’t small it, both bee and spider chose randomly. Good chances that the crab spider learned what the insects like! Follow the nose!
Another study compares the introduced European honeybee Apis mellifera (that has been used in the study above) with native bees Austroplebia australis in Australia. Obviously the bees that co-evolved with crab spiders in Australia knew how to find them, and avoided this threat. The European bees in Australia have not yet learned to spot crab spiders and got caught much more often.
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