You wouldn’t think mimicking an ant would be all that effective against a hungry predator. For one clever species of jumping spider, however, it’s a literal lifesaver.
Siler collingwoodi, the spider in question, stands out like a sore thumb in the wild, its tiny body covered in vibrant shades of blue, orange, and red. To combat this loud appearance, it pretends to be an ant, raising its front legs to imitate antennae, bobbing its abdomen, and taking exaggerated steps to appear as ant-like as possible.
Few behaviors are more fascinating among wildlife than mimicry. To us, it’s clearly a spider doing an ant impression. Ants aren’t brightly colored, first of all. Not to mention, the spider’s performance is less than perfect. Who does it think it’s fooling?
Predators, that’s who. Though not enough to fool us, the jumping spider’s insect impression is more than enough to pull the wool over the eyes of many potential predators.
In addition to being the cutest spider species, jumping spiders could also be classified as the friendliest, if for no other reason than that they have no real means of self-defense. Meanwhile, as anyone who’s ever accidentally trodden across an ant bed can attest, ants can be quite vicious.
To protect themselves from predators, they’ll use every weapon in their arsenal. This means employing their deadly jaws, venom, and stingers against attackers – oftentimes swarming as they do so. Who can blame a would-be predator for looking for easier prey?
Ants are such a poor choice of meal, in fact, that jumping spiders aren’t the only species to mimic them. Hundreds of spider species imitate ants to avoid becoming lunch.
To investigate this intriguing behavior, researchers conducted a study, published in the journal iScience, in which they collected ant-mimicking spiders, a type of jumping spider that does not mimic ants, and five ant species to serve as models.
“Ant imitation is an effective defense strategy as ants are generally unappetizing to predators due to their prickly bodies, chemical defenses, venom, and their readiness to retaliate,” study author Dr. Hua Zeng explained in a media release.
Is the jumping spider’s ant imitation effective?
So, just how effective is the jumping spider’s ant imitation? How often does it work against predators? The short answer is: sometimes.
When they tested the spider’s thespian abilities against a praying mantis, they did next to nothing to help. The praying mantis hunted the Siler collingwoodi equally as often as the non-mimetic spider.
Like ants, praying mantises are absolutely ferocious. Unlike ants, mantids are massive insects capable of bringing down far larger threats (or prey) all on their own with their raptorial arms and powerful mandibles. As a result, they likely don’t fear ants as much as other insects and arachnids might.
Testing the jumping spider’s mimicry against another species of jumping spider – yes, they can and do cannibalize each other – scientists found the prey spider’s acting much more beneficial. The predatory spider avoided Siler collingwoodi entirely, attacking only the non-mimetic spider.
“For the spider predator, a random attack on an ant could result in injury,” Dr. Zhang explained. “So they are very cautious predators and will only attack if they can distinguish S. collingwoodi from ants with a high degree of certainty.”