16 Intriguing Insights About Daddy Longlegs

You’ve probably come across various claims about daddy longlegs. Perhaps you’ve been told they are spiders or that their venom is so potent humans are fortunate their fangs are too short or weak to cause harm. However, not all these statements are accurate. To delve deeper, Mytour consulted Ron Clouse, an expert who has spent over a decade researching the DNA and ancestry of these frequently misunderstood arachnids. "My work spans from field collection to data analysis, lab tests, and publishing findings," Clouse shared with Mytour in 2014. Here’s what you need to understand.

1. Daddy longlegs are not spiders …

While they belong to the arachnid family, they share a closer kinship with scorpions than spiders. Unlike spiders, they lack silk-producing abilities, possess only one set of eyes, and have a unified body structure without the distinct “waist” seen in spiders.

2. … And they’re not venomous.

The myth you might have heard at summer camp—that daddy longlegs are the most venomous creatures on Earth but lack the fang strength to harm humans—is entirely false. In reality, they don’t possess fangs or the ability to produce venom. Clouse suggests this misconception may have originated from an American tabloid misinterpreting an Australian study on the venom of a local species referred to as ‘daddy longlegs,’ which is actually a cellar spider (Pholcus phalangioides). To add to the confusion, crane flies are also sometimes called daddy longlegs.

3. They’ve been around for an incredibly long time.

“A remarkably preserved fossil of a daddy longlegs discovered in Scotland confirms their existence dates back at least 400 million years,” Clouse explained. “This ancient specimen closely resembles the long-legged species we observe today. It’s theorized that daddy longlegs diverged from scorpions around 435 million years ago, as scorpions began adapting to land. To put this into context, this was approximately 200 million years before dinosaurs emerged, which themselves roamed the Earth for only about 165 million years.”

4. Daddy longlegs are known by several other names.

In North America, their name is largely derived from their distinctive long, slender legs. However, globally, they are referred to by various names. “In different regions, their common names highlight unique traits of the species found there,” Clouse noted. “For instance, in South America, the larger, shorter-legged varieties are often named for their strong odors. In Europe, terms like ‘harvestmen’ and ‘shepherd spiders’—along with their scientific name, Opiliones—connect them to fertile pastures, harvest time, or their resemblance to shepherds on stilts or the shape of a scythe.”

5. They inhabit nearly every corner of the globe.

These arachnids are present on every continent except Antarctica. “They thrive in humid environments, such as beneath rocks, within leaf litter, and inside caves,” Clouse shared. “Tropical regions, with their moist climates and dense vegetation, host the greatest diversity of species. Each part of the world has its own unique daddy longlegs, many of which are small and hidden in the leaf litter of forest floors. Even in the U.S., there are tiny species in leaf litter that most people never encounter.”

6. Daddy longlegs exhibit a remarkable diversity of species.

Estimates suggest there could be up to 10,000 species of daddy longlegs, with 6,000 to 7,000 already identified. “We’re constantly discovering new species,” Clouse explained. “Their limited mobility often leads to speciation, as natural barriers like rivers or mountains isolate populations, causing them to evolve into distinct species.” For instance, the closest relatives of the arachnids he studied in South Carolina are found in West Africa, remnants of a time when the continents were connected before the Atlantic Ocean formed.

This tendency to diversify results in a wide array of appearances among daddy longlegs, with each species typically confined to a small geographic area. “One mountain peak may host a unique species, while another peak has its own distinct variety,” Clouse noted. In Pennsylvania, they feature small, pod-like bodies with elongated legs. The cyphos species Clouse researched are diminutive with short, sturdy legs. In Laos, a species with a legspan of 13 inches was identified in 2012, while the Gonyleptidae family in South America boasts spines and striking colors. “Their unique traits make every species fascinating,” Clouse remarked.

7. Daddy longlegs often gather in large groups.

This clustering behavior is common among daddy longlegs, Clouse explained. While the exact reason remains unclear, scientists have proposed several theories. “It might be a response to dry conditions, helping them retain moisture,” he suggested. “Alternatively, they could be grouping to reduce the risk of predation or to enhance their collective chemical defenses.”

8. They are not very mobile.

Despite their long legs, these arachnids are surprisingly sedentary. DNA analysis of coastal Brazilian populations revealed that “they hardly move at all. They stay in one place,” Clouse noted. “Their daily routine involves hiding in crevices until evening, when they emerge to sit on leaves overnight. At dawn, they return to their crevices. Their lengthy legs seem to serve primarily for male competition or attracting mates, as they don’t use them for movement.”

Regarding why they are so stationary, Clouse explained, “It’s likely tied to their need for humidity, feeding habits, and mating behaviors. Even after 40 million years, they haven’t evolved the ability to travel extensively. They simply don’t move much.”

9. Daddy longlegs employ unique strategies to evade predators.

Birds, frogs, and lizards often prey on daddy longlegs. To avoid becoming a meal, these arachnids use several tactics, including forming groups. “One of their primary defenses is secreting chemicals from glands on their bodies, which deter predators,” Clouse explained. “They are also masters of camouflage. Many hide in crevices during the day, and when threatened, they curl up and remain still for several minutes.” Playing dead is highly effective for them. “Their brown coloration blends perfectly with leaf litter, dirt, and debris, making them nearly invisible,” Clouse added. “Predators often lose sight of them once they stop moving. When they freeze, they vanish.” Watch a video of a cyphos playing dead here.

10. They practice self-grooming.

Many species engage in leg threading: “They pass one leg at a time through the small pincers near their mouths,” Clouse said. “While other species may groom differently, this behavior is crucial for removing parasites. You’ll often spot tiny red mites on areas they can’t reach.” Watch a daddy longleg leg threading in the video above.

11. They have surprisingly long lifespans.

Larger species, such as those Clouse researched in Brazil, typically have a lifespan of under two years. However, the smaller cyphos might live for as long as seven years. Clouse noted, 'Body size isn't a reliable indicator of lifespan. Unlike many insects, several can endure multiple seasonal cycles in their adult stage. The most short-lived are likely the long-legged varieties found in the U.S., which, after a brief juvenile phase, may only survive a few additional months as adults.'

12. Once lost, their legs are gone for good.

For those who as children removed a leg from these creatures, it's time for a bit of remorse: those limbs do not regenerate. 'We observe injured individuals—they might have a segment missing at the end, likely from a predator's bite,' Clouse explained. 'Generally, creatures with exoskeletons can't heal injuries until their next molt. However, adult daddy longlegs cease molting. 'I suspect that if a juvenile, or nymph, suffered a leg loss or injury, it might partially recover,' Clouse added. 'During its next molt, it might appear deformed, but a new leg could begin to form. It's common to see these long-legged creatures with six or seven legs. They lack the regenerative abilities of starfish.' This is particularly unfortunate for species that lose legs to escape predators or during male combat, where they use their large spines to try and sever their rivals' hind legs.

13. The dietary habits of daddy longlegs remain a mystery.

'In their natural habitat, where the larger species reside, my colleagues often find them already consuming something, which is quite frustrating!' Clouse remarked. 'It's challenging to determine if they've hunted it or simply stumbled upon it. Essentially, they lack fangs and powerful pincers. Some smaller species possess robust pincers, enabling them to seize and crush minuscule insects in the leaf litter. However, aside from a few families, most don't appear to be adept hunters. Thus, we presume their diet consists of scavenging on carcass fragments, remnants, and debris. Not the most thrilling menu.'

14. Many aspects of their reproductive behavior remain unknown.

Some species, such as the tiny cyphos Clouse researched, are so minuscule and elusive that their mating habits and egg-laying processes are largely undocumented. 'The only thing we’ve observed about these seed-like creatures is that males often possess unique glands absent in females,' he explained. 'It appears they produce a chemical substance to lure females.'

Here’s what we understand about cyphos reproduction: 'The male produces a sperm packet, which he transfers to the female in a spherical form,' Clouse stated. The subsequent steps, however, remain unclear. 'She likely opens the packet and absorbs the sperm, which remains viable until it reaches her reproductive tract and fertilizes the eggs.' The female then employs an elongated, telescopic ovipositor to deposit the eggs deep into the soil.

Larger species exhibit more observable mating behaviors, and Clouse has witnessed some fascinating rituals. 'In Brazil, I’ve observed larger species engaging in intricate mating displays,' he shared. 'The male approaches the female, touching her repeatedly, while she appears to assess the situation.' Most daddy longlegs species 'involve the male transferring sperm directly into the female,' Clouse noted. 'However, the exact mechanisms of how she processes it and how their reproductive systems interact remain partially unknown.' On one occasion, Clouse and his team observed a large female in Brazil laying 30 eggs coated in a slimy substance on a leaf. 'She secretes a concentrated fluid that, upon contact with humid air, expands into a protective jelly,' he described. 'This likely shields the eggs from fungi and other threats.'

15. Males and females often exhibit distinct differences, though 'sneaky males' are an exception.

'In certain species, males possess significantly longer legs than females,' Clouse explained, 'while in others, males have glands or protrusions absent in females. The purpose of these features remains unclear.' However, some species exhibit two types of males, Clouse noted: 'One type is distinctly different from females, while the other closely resembles them. It’s believed that the latter can approach females unnoticed, avoiding fierce competition with other males.'

This phenomenon isn’t as unusual as it seems; Clouse mentioned it occurs in various animals where male competition is influenced by female preference. For instance, in fish, these males 'display the coloration and size of females, but they’re not female,' Clouse said. 'They slip past other males unnoticed, positioning themselves near females. Before anyone realizes, she releases eggs, he releases sperm, and the process is complete.'

In daddy longlegs, typical males are referred to as alpha males, while those resembling females are called beta males. In systems with alpha and beta males, beta males are always a minority at any given time. 'There’s a limit to how many sneaky males can exist,' Clouse stated. 'If their numbers grow too high, they start interfering with each other, giving alpha males the upper hand. Females still prefer larger, stronger males, so sneaky males remain a small, consistent portion of the population over time. If a female carries the gene to produce more sneaky males, she gains an advantage when their numbers are low. However, if their population increases, the trait becomes less common. This balance fluctuates around a specific percentage.'

Whether a male is an alpha or a beta, their goal remains the same. 'They exhibit all the same instincts,' Clouse said. 'They desire to mate with females; they just don’t appear male.'

16. Researchers discovered a male daddy longlegs preserved in amber in a particularly vulnerable position.

Discovered in 2016, the Halitherses grimaldii specimen, preserved in tree sap 99 million years ago, was found with an erect penis. According to Discover, the organ was nearly half the length of the creature's body, featuring a heart-shaped tip and a coiled end designed to transfer sperm to females through an opening near their mouths. This marked the first time a harvestman was observed in such a distinctive state. Typically, the penis remains internal, leading scientists to theorize that the creature had either just mated or that the stress of being trapped in the resin caused its hemolymph (blood) pressure to rise, resulting in the erection.