Head to head
Emperor Scorpion vs Goliath Birdeater
Scorpions and spiders are the two arachnid groups people fear most, and they are often lumped together, but they are as different from each other as, say, a crab is from an insect. The emperor scorpion and the goliath birdeater tarantula are both among the largest members of their respective groups, both come from tropical rainforest, both live in burrows, and, contrary to their menacing size, both are close to harmless to humans.
| Emperor Scorpion | Goliath Birdeater | |
|---|---|---|
| Body plan beyond the 8 legs | Two pincers and a stinging tail | Fangs and silk glands; no tail |
| Size | Up to about 20 cm long | Leg span up to about 30 cm; heaviest spider by mass |
| Native to | Rainforests of West Africa | Rainforests of northern South America |
| How it subdues prey | Crushes with the large pincers; stings rarely | Bites with venom-injecting fangs |
| Main defence against predators | Pincers and a sting like a bee | Hissing, flicking barbed irritant hairs, and a wasp-sting bite |
| Web | None; ambushes from a burrow | None for catching prey; lines the burrow with silk |
| Under UV light | Glows blue-green | Does not glow |
| Danger to a healthy adult | Low; painful sting at worst | Low; painful bite and itchy hairs at worst |
Scorpion vs Spider: common questions
What is the actual difference between a scorpion and a spider?
Both are arachnids, so both have eight legs, two body sections, no antennae, and no wings, and both are predators that mostly liquefy their prey and suck it up. The differences are in the extra equipment. A scorpion has a pair of pincer-tipped pedipalps at the front for grabbing, and a tail, technically the rear part of the abdomen, ending in a bulb and a curved stinger that injects venom. A spider has small pedipalps, not pincers, a pair of hollow fangs that inject venom, spinnerets at the rear that produce silk for webs, egg sacs, draglines, and wrapping prey, and no tail at all. Scorpions also give birth to live young and carry them on their backs, while spiders lay eggs in a silk sac.
Which is more venomous, this scorpion or this spider?
Neither is medically significant, and that surprises people because both are so large. The emperor scorpion has weak venom and a sting comparable to a honeybee's, and it prefers to crush prey with its heavy claws rather than sting; among scorpion keepers it has a reputation as one of the calmest species. The goliath birdeater's venom is likewise mild to humans, causing local pain, some swelling, and sweating, similar to a wasp sting, though its sheer fang size means the mechanical wound is notable. As a rule, the most dangerous scorpions, such as the deathstalker and various bark scorpions, and the most dangerous spiders, such as the Brazilian wandering spiders and Sydney funnel-webs, are all far smaller than these two giants. Size and danger are not related in arachnids.
Does the goliath birdeater really eat birds?
Hardly ever. The name comes from an 18th-century engraving showing a related tarantula eating a hummingbird, and it stuck to the whole group. In reality the goliath birdeater is a ground-dwelling ambush hunter that feeds mainly on large insects, earthworms, other spiders, amphibians such as frogs and toads, and occasionally small snakes, lizards, or rodents that blunder near its burrow. A nestling bird taken from a low nest is possible but exceptional. The spider has poor eyesight and hunts by detecting vibrations, waiting at its burrow entrance and rushing out to grab and bite anything of the right size that passes.