This past Wednesday was Valentine’s Day! Whether you’re single or paired up with a loved one, we can all take advice from peacock spiders.
The best way to someone’s heart…is to DANCE.
Peacock spiders are tiny jumping spiders in the genus Maratus found almost exclusively in Australia (one species is found in China). You can find peacock spiders in a wide range of habitats, but some species are more specialized and live in specific environments. All peacock spiders are small, about the size of a grain of rice (2 – 6 mm, or about 1/16 – 1/4 inches). While females are typically brown or beige, male peacock spiders usually have a colorful abdomen that spreads like a peacock’s tail to attract females (hence their name).
Exactly how many species are there? We don’t know! Peacock spiders slid under science’s radar until recently – there were only seven named species of peacock spiders in 2011. Today, there are at least 86 species, with more being classified as scientists find them.
We know about so many more species of peacock spiders in part due to improvements in camera technology. As cameras improved, scientists could see and identify differences between these tiny spiders. Each species has a unique coloration and mating dance that can be used for identification. Each species’s scientific and general names are also often based on the patterns found on the male spiders. My favorite name, though, is the one given to Maratus jactatus: Sparklemuffin.
A jumping spider
Peacock spiders are jumping spiders, a group of evolutionarily similar spiders that make up the family Salticidae. In fact, jumping spiders are the largest spider family in the world, with around 13% of all spiders belonging to Salticidae.
And, as you might expect based on their name, jumping spiders are good at jumping! A peacock spider can jump 40 times its body length.
Like other jumping spiders, peacock spiders rely on jumping for successful hunting. They do not make webs and instead stalk their prey. When they are close enough, peacock spiders jump on their food item and kill it with venom. A peacock spider can kill an insect three times their size. Don’t worry about them hurting us, though – peacock spiders are so tiny that their jaws can’t break our skin!
Their eyes!!!!
Peacock spiders have exceptionally good vision for their size. They can perceive both motion and depth much better than animals of a similar size. One paper describes them as approaching “the physical limit of optical resolution for their compact size.” Peacock spider vision literally can’t get much better. And just how good is it? Human vision is only about 5 to 10 times better in acuity!
And in terms of color vision, peacock spiders easily outmatch us. Compared to the three color channels in our eyes, peacock spiders have as many as four channels and can even see ultraviolet light (humans can’t see UV).
Peacock spider eyes may be the foundation underneath their current lifestyle. As predators, keen eyesight helps them find and capture their prey. Their eyes have also likely helped peacock spiders find and navigate new habitats, potentially contributing to their spread across various habitats. Most interestingly (in my opinion), their keen eyesight likely led to the evolution of complex visual signals during mating.
Dancing King
And wow, do peacock spiders have some fun mating dances.
In most species, the male peacock spider has a pair of fuzzy, elongated legs. They also have lateral flaps on their abdomen. When these lateral flaps are unfolded like a peacock’s train, the male spider shows off a species-specific pattern of colors. These colors are made from scales that can reflect visible and ultraviolet light; some species even have iridescent scales made by specialized scales shaped like an airplane wing with ridges to diffract light.
Male peacock spiders usually try to grab a female’s attention by waving their fuzzy third pair of legs. Once a female is looking, he will unveil his tail and start waving it. His dancing movements are eye-catching with their color and produce vibrations to further pique a female’s interest. One of the first things a male does is start producing ‘rumble-rumps,’ the official term for the vibrations made as he moves his abdomen.
Depending on the species and how into him the female is, a male peacock spider’s mating dance can range from a few minutes to over an hour. If the female is interested and doesn’t attack the male, he’ll approach her for the final act of his show. He will use specific moves in his pre-mount display to produce vibrations called ‘crunch-rolls’ and ‘grind-revs.’ With his dance complete, the male then mates with the female.
What if the female isn’t interested in his dance? Whelp, there’s a good chance the male will get eaten unless he manages to escape. Unfortunately for the males, female peacock spiders tend to be very choosy about their mates, and they’re totally uninterested in a second partner if they’ve already mated.
Such is life in a peacock spider’s world: you either dance well, or there’s a good chance you’ll die.
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