 Ever wondered who would win in a fight between a tarantula and a scorpion? This question is part of our Who Would Win video series, where we get wildlife experts to dream up hypothetical battles between animals, all in the name of science. On Team Scorpion we have tough armour in the form of a hardened exoskeleton made of overlapping layers of chitin, a protein similar to keratin in our nails. Turantulins also have grasping pinces they use to catch and tear apart prey. Over 2,500 species of scorpion are found worldwide, and one of the largest, the giant forest scorpion, can grow up to 22 centimetres long. But Team Turantula also has size on its side. For example, the Goliath bird eater in South America, one of over 900 tarantula species, has an impressive body length of 12 centimetres, with legs spanning nearly 30 centimetres, the size of an A4 page. And what spiders lack in pinces, they make up for with metal tip fangs, which can easily punch through chitin and inflict painful puncture wounds. Many tarantula species also have urticating hairs, which are barbed bristles, flung from the abdomen that can severely irritate soft mammalian skin and eyes. They both have a superweapon in their arsenal, venom. These are complex cocktails of thousands of different molecules that target the nervous system, fine-tuned by hundreds of millions of years of evolution to be fast-acting, potent, and selective. Scorpions inject their venom by the stinger in their tail, and tarantulas inject theirs via their fangs. Scorpion stings have caused over 3,000 fatalities worldwide, and generally, the smaller the scorpion pinces, the more potent the venom. Meanwhile, tarantula venoms are generally not considered dangerous to humans, with no recorded fatalities to date. However, in Southeast Asia, tree-dwelling, brilliantly coloured ornamental tarantulas can move with lightning speed, and inject large amounts of very potent venom, causing extreme pain and muscle cramps that can last for weeks. So the fight appears evenly matched at first glance. The Deathstalker scorpion, for example, can whip its stinger at 128cm per second in a defensive strike, but the Texas brown tarantula can sprint at similar speeds. If the scorpion gets the first sting in, the tarantula may try to retreat. The scorpion could then use its grasping pinces to grab and tear the tarantula apart. But some tarantulas appear to be resistant to scorpion venoms, even when that venom may be lethal to us. This may be because tarantulas have evolved different nervous systems from ours, or the tarantula may even have a natural means of detoxifying the scorpion venom. This time, let's say the tarantula strikes first. The tarantula flings its urticating hairs for a special attack. The barbed bristles are ineffective against the scorpion's tough exoskeleton. The tarantula then uses its metal tip fangs, easily puncturing the scorpion's exoskeleton armour. The tarantula wins. So overall, this battle of the arachnids depends on the size, speed and venom of the contenders. And our venom expert puts her money on the tarantula. What animals would you want to see battling it out in our arena next?