Why is it that some of the NW slings have such beautiful colors? I have T.gigas, P. ermenia, GGB, P.pulcher, A. versicolor,and P. cambridgi and they are neat, but why so colorful? It would seem they would be easier to see by predators.
There are many reasons why something like that might want to be brightly colored. Perhaps the colors are warning colors, warning the potential predator that the sling may pack a punch. The warning coloration can also be a bluff that mimics other, more dangerous species' coloration and patterning. Another reason could be that certain predators perceive certain colors differently. A brightly colored sling to us, could look drab colored to, say, a bird. Perhaps the bright blue of A. versicolor slings actually come up as green to its predators and thus is makes it easier to hide amongst foliage. In Idiothele mira, the it is speculated that the blue feet are used to attract unsuspecting prey.