Scientists have documented the existence of numerous arthropods that make use of mimicry in order to avoid being spotted by predators. The degree of viciousness inherent in a particular arthropod’s nature varies from species to species. Some arthropods are relatively passive while others are relatively predacious. When considering those arthropods that do not possess many, or any defensive features of significance, merely looking like a more predatory creature can intimidate predators that would otherwise not hesitate to attack. This particular type of mimicry is known as “Batesian mimicry.” There are several different types of arthropod mimicry, and not all involve one arthropod species resembling another. For example, a type of orbweaver spider avoids predatory attacks by using its web decorations to mimic a spot of bird dropping, which is poisonous and deadly to arthropods when consumed.
The term “masquerading” is used to describe arthropods that possess the particular colors and body shape necessary to mimic the appearance of certain inanimate objects as opposed to mimicking other arthropods. “Crypsis” is when an arthropod’s body coloration resembles its background, which can have the effect of obscuring an arthropod’s spatial position or it can simply allow the arthropod to avoid detection altogether. The orbweaver spider species known as Cyclosa ginnaga, uses the remains of prey carcasses, egg sacs, plant detritus, and/or silk to create disc-shaped web decorations that function to obscure the spider from predators. The shape, size and color of the Cyclosa ginnaga species’ body is such that it resembles a spot of bird droppings when it remains motionless above the white web decoration that they produce. Like most forms of animal waste, bird droppings contain numerous pathogens and fungal species that can cause disease in humans and all other animals, including arthropods. Studies have shown that spider predators, including birds, are unable to discern between a spot of bird dropping and the Cyclosa ginnaga spider while obscured by its disc-shaped web decoration. The particular body colors and body size of the Cyclosa ginnaga spider species combines with its web decorations to form a bird dropping masquerade as a method of avoiding detection by predators.
Have you ever touched a plant or some other organic product only to find that it was a spider or insect?
