30+ Interesting facts About Spiders

1. Spiders are members of arachnids, which also include scorpions, mites, ticks, and daddy longlegs.
2. There are more than 45,000 spider species in 110 families. Their predatory habits provide more good than harm to the environment and gardens. They eat insects equal to the weight of humans on earth, most of which are herbivores, granivores (seedeaters), and other harmful insects. However, they also consume some beneficial insects like butterflies and honeybees. (Source)
3. The water spider, or the diving bell spider, is the only aquatic spider species that permanently lives underwater. They live in freshwater habitats with abundant vegetation and are present in Siberia and (northern and central) Europe.
4. Spiders appeared on earth around 315 million years ago. A 100-million-year-old spider fossil inside an amber shows that ancient spiders had a tail. (Source)
5. All spiders produce silk, but only a few species construct webs. These webs have different shapes, sizes, and features to catch prey. Common web types include orb, funnel, sheet, tangle, radial, purse, and lace.
6. Apart from making webs, spiders also use silk for various functions. These include trapping prey, transportation, and courtship.
7. Few spiders can produce multiple types of silk. Each contains individual feature like strength, stickiness, and elasticity.
8. Spider silk is five times stronger than steel. Each strand of the silk is 1000 times thinner than human hair and composed of thousands of nanostrands. There are 20 micro-loops per millimeter of spider’s silk, giving it enormous strength. (Source) 

   

   Spider's silk is lightweight yet stronger than steel

   
   
9. The dragline silk by spiders is lightweight, strong, biodegradable, and biocompatible (not attacked by an animal’s immune system). Spiders produce an insignificant amount of silk, and its production by plants, yeasts, and other animals is expensive. However, genetically modified marine bacteria can assist in the mass production of eco-friendly and sustainable dragline silk. (Source)
10. Bagheera kiplingi, a jumping spider, is the only spider species with a primarily herbivorous diet of the acacia tree. However, this spider in Costa Rica and Mexico sometimes eats ant larvae. (Source)
11. Spiders are carnivores that eat insects, centipedes, frogs, lizards, birds, and other spiders. They usually eat an alive or a recently killed animal.
12. Spiders are beneficial due to their consumption of pests (cockroaches, flies, etc.) and disease-borne insets (mosquitoes) in homes. Most spiders are venomous, but only a few, like widow spiders and recluses, can cause harm to humans. (Source)
13. Spider venom has several medical and agricultural benefits. Potent peptides in their venom can treat cancers, stroke, erectile dysfunction, and pain. Its insecticidal activities make it an environment-friendly insecticide. (Source)
14. The male Sydney funnel-web spider, native to Sydney and its surroundings, is the most venomous among spiders. Only 0.2 mg/kg of its venom is lethal to humans and other primates. The female Sydney funnel-web spider is comparatively four to six times less venomous. (Source)
15. Spiders use hairs on their legs for various purposes. They are used for feeling, listening, tasting, and smelling. Few species have specialized hairs on their feet that assist them in gripping flat surfaces.
16. Unlike other arthropods, spiders have a centralized nervous system, having concentrated in their cephalothorax.
17. Spiders immobilize their prey by injecting venom through the bite or by wrapping silk around the victim.
18. Spiders digest their food outside the mouth. They release digestive enzymes on prey while biting or chewing.
19. Most spiders have eight eyes, some have six, while cave-dwelling spiders have no eyes. Two large central eyes can see color images and determine the distance. Spiders cannot turn their heads due to the absence of necks, and secondary eyes on the sides compensate for this by detecting the movement of prey or predator. However, most spiders have weak eyesight and use the senses of taste and touch for various tasks. (Source)
20. Flattie spiders have the fastest leg-driven turn among land animals. When striking prey, it can spin at 3,000 degrees per second. This spinning movement is one of the fastest on earth after fruit flies and hummingbirds. (Source)
21. The Moroccan flic-flac spider, a nocturnal spider in a sand desert in Morocco, is the only spider that moves with flic-flac jumps. In contrast to the golden rolling spider, which can only roll down dunes, this spider can undertake this locomotion on flat ground, uphill and downhill. It uses this movement while running from predators and doubles its speed compared to the walking mode. (Source)
22. Most spider species live independently, while species in eight families are permanent-social. They form colonies that can contain dozens and up to hundreds of members. These social spiders are more intelligent and have social behaviors like sharing food.
23. Common house spiders live from a few years to seven years. Tarantulas can live for 20 years or more. The oldest known spider was an Australian female trapdoor that died at 43 after being killed by a parasitic wasp in 2018. (Source)
24. Female spiders are usually bigger than males. In some orb-weaving spider species, females can be 12 times longer than their male counterparts. The large size assists females in reproducing a large number of offspring. Smaller males can run away from predators faster, easily reach receptive females for mating, and have an efficient “bridging” locomotion. (Source) 

    

    Female orb-web spiders can be 12 times longer than males

    
    
25. Larger female spiders usually consume males after mating. However, males in several species can protect themselves. In a species of orb-weaving spiders, males flee from females after mating through faster movement of their legs. Only the slower males become victims of their mate. The surviving males can again mate with females. (Source)
26. All spiders molt when young, while this process continues in some species throughout their lives. Males in some species mate with females during molting to avoid sexual cannibalism. According to research, this strategy can increase the male survival rate to 97%, compared to 20% in conventional mating.
27. The goliath bird-eating spider is the largest species. The largest recorded was a male with a leg span of 11 inches (28 cm). These spiders are native to rainforests in South America. (Source)
28. Comparatively, the smallest is the Samoan moss spider. Its length is nearly 0.11 inches (0.4 mm). Other members of this spider family, present in all continents except Antarctica, are also tiny. (Source)
29. Bolas spiders are among the orb weaver spiders. They are famous for their unique hunting technique, capturing prey by swinging the thread with sticking material on flying insects. It is similar to bola, a weapon used by South American Indians.
30. Spiders are present in all continents except Antarctica. There are more species in the tropics than in the temperate regions.
31. Female spiders give eggs in egg sacs made of silk. A sac may contain a few to a thousand eggs in various species. In many species, females die after producing the last egg sac, while others protect the young.