Scorpions Are Predators With a Sensitive Side
Look past their grasping claws and lightning-fast stingers, and you’ll see scorpions have a delicate pair of comb-like organs on their belly called pectines. These sensory body parts help them navigate, and figure out who’s a menace, a meal or a mate.
Powerful pincers. Paralyzing venom. Armor fortified with iron and zinc. Theyâre totally metal.
The scorpion has a fierce reputation thatâs lasted through the ages. Its ancestors were some of Earthâs earliest predators. But this beast has a secret â a softer side.
If you flip over a scorpion â donât try this at home â its belly is sensitive, and not just because its armor is thinner there. Right behind its legs, youâll see a couple of comb-like organs.
These are pectines, and every scorpion has a pair. The comb teeth are covered in tiny sensors called peg sensilla.Â Every peg sensillum has a slit-shaped pore that takes in chemical traces from the ground and air. Each is attached to roughly a dozen nerve cells. This helps the scorpionâs brain read the chemicals, to understand its environment. Itâs similar to how we taste and smell.
Thatâs useful, because even though it has many eyes, a scorpionâs vision is not the best. When two scorpions meet, they use their pectines to sense each otherâs pheromones â invisible chemical signals they release into the world around them. This helps them determine whoâs a menace, meal, or potential mate.
Looks like these two are a match. Theyâre not fighting, theyâre â well â holding hands and kissing, scorpion style. And this is their version of a slow dance.
The male deposits a packet of sperm on the ground inside a casing called a spermatophore. She picks up what she needs, and just like that, this brief but sweet courtship is over.
The peg sensilla are also sensitive to physical cues. They brush the ground as the scorpion walks, deciphering textures that help it navigate. But the pectines arenât its only specialized sensors.
The scorpionâs dainty feet and hairs all over its body also help it pick up minuscule vibrations.
Fossils show scorpions have existed in some form or another since before the dinosaurs. At night, researchers can find scorpions because they glow under a simple UV flashlight. Why this is, is a mystery.
Today, there are more than 2,000 species found all over the planet. And scientists are still discovering more.
Thereâs so much pressure out there to be tough, smart, fast. Maybe the real trick to survival is cultivating your sensitive side, Â for hundreds of millions of years.
Hey, itâs Laura. Need some more arachnids like these scorpions in your life? I thought so. Let’s keep things going with this spider playlist.
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