Both male and female spiders produce silk, and in many species both sexes build webs at some point in their lives. The popular image of a spider patiently sitting in a large, elegant web is overwhelmingly a portrait of a female, though, because in the majority of web-building species adult males abandon prey-capture webs after their final molt. Males instead redirect their silk toward courtship, mating, and survival in ways that look nothing like the classic orb web. The split between male and female silk use turns out to be one of the more striking examples of sex-based behavioral divergence in the animal kingdom.
Why Females Are the Primary Web Builders
In orb-weaving spiders and many cobweb-building species, the female is dramatically larger than the male. Golden orbweavers (family Nephilidae) illustrate the extreme end of this: phylogenomic analyses show that male and female body sizes evolve independently, with male size driven toward an optimum that may lie between roughly 3 and 5 mm, while female size follows no such constraint and can balloon to many times that length.1Systematic Biology. Golden Orbweavers Ignore Biological Rules: Phylogenomic and Comparative Analyses Unravel a Complex Evolution of Sexual Size Dimorphism A large female needs far more food than a tiny male, and a full-sized orb web is an expensive, calorie-intensive structure. It makes energetic sense for the sex that needs the calories to invest in the architecture that captures them.
After their final molt, males of many orb-weaving species stop building capture webs altogether. Their priorities shift abruptly from feeding to finding a mate. A small male wandering from web to web is under intense time pressure: he may live only weeks as an adult, and the longer he spends maintaining a web of his own, the fewer females he encounters. So he abandons web construction, lives off stored reserves or occasional scraps, and devotes his remaining silk to reproductive tasks.
How Males Use Silk During Courtship
Males may stop building webs, but they do not stop spinning. In orb-weaving species like the St. Andrew’s cross spider (Argiope keyserlingi), males construct a specialized “mating thread” attached to the female’s web. The male hangs upside down from this thread and uses his legs to strum and pluck it, interspersed with vigorous bouncing, essentially performing a vibratory courtship dance transmitted through silk. He continues this performance until the female moves onto the mating thread and assumes a copulatory position.2PubMed Central. The Influence of Vibratory Courtship on Female Mating Behaviour in Orb-Web Spiders (Argiope keyserlingi, Karsch 1878) The mating thread is a male-built silk structure, but it is nothing like a prey-capture web. It serves as a communication channel and a stage.
Males also spin small “sperm webs” onto which they deposit sperm before loading it into their pedipalps, the specialized appendages used to transfer sperm to the female. This is a universal behavior in male spiders: even species that never build a conventional web at any life stage still produce silk for this purpose. The sperm web is a tiny, temporary sheet, quickly discarded, but it is an indispensable piece of silk engineering.
Web Reduction in Black Widows
One of the more unusual male silk behaviors involves actively dismantling a female’s web. In western black widows (Latrodectus hesperus), courting males excise and bundle sections of the female’s web, wrapping the removed silk with their own. This “web reduction” behavior has a measurable effect: webs that males had reduced attracted about three times fewer rival males than intact webs.3Animal Behaviour. Web reduction by courting male black widows renders pheromone-emitting females’ webs less attractive to rival males When researchers experimentally removed a similar proportion of silk without adding male silk, those webs still attracted just as many males as intact ones. The male’s own silk, layered over the bundled remnants, appears to be the key ingredient that masks the female’s pheromone signals and cuts down on competition.
There is more to web reduction than rivalry suppression, though. A separate study found that the amount of web a male tears down is best predicted not by his own body condition or by the web’s size, but by the female’s aggression level. Males confronting more aggressive females reduce more of the web. The researchers concluded that web reduction’s primary function is to calm the female and lower the risk of sexual cannibalism.4Behavioral Ecology and Sociobiology. Bringing down the house: male widow spiders reduce the webs of aggressive females more So the male black widow is simultaneously a silk builder and a silk destroyer, producing his own while strategically removing hers.
Bridal Veils and Copulatory Silk Wrapping
Some male spiders take a more direct approach to managing the danger of mating with a larger, potentially cannibalistic partner: they wrap the female in silk. This behavior, called “bridal veil” deposition, was first described in crab spiders (Thomisidae) in 1931, when a researcher noted that males laid silk threads over the female’s body during courtship. The hypothesis was straightforward: immobilizing the female, even loosely, could prevent her from attacking.5acta ethologica. Fifty shades of silk: sexual behavior and bridal veil deposition in the spider Ctenus longipes
In the nursery web spider (Pisaurina mira), males combine this silk-wrapping behavior with unusually long legs relative to body size. Males use those legs to help wrap the female’s legs with silk before and during copulation. Experimental work suggests that both traits, the elongated legs and the copulatory silk wrapping, are sexually selected: males that wrap more effectively have greater reproductive success, and the wrapping appears to reduce the likelihood of being eaten.6PubMed Central. Benefits of size dimorphism and copulatory silk wrapping in the sexually cannibalistic nursery web spider, Pisaurina mira This is silk production with a very different function from web building, but it is unmistakably a male silk behavior, and one that requires both precision and courage.
Silk Glands That Only Females Have
While both sexes share most types of silk glands, at least one category is genuinely female-exclusive in the vast majority of spiders. Cylindrical glands (also called tubuliform glands) and their associated spigots are found only in female spiders under the prevailing scientific understanding, and they produce the silk used to construct egg sacs.7PubMed Central. Hers and his: Silk glands used in egg sac construction by female spiders potentially repurposed by a ‘modern’ male spider In the giant wood spider (Nephila pilipes), for instance, three pairs of cylindrical glands develop in females and play a central role in the successful production and protection of eggs.8International Journal of Advanced Research in Science, Communication and Technology. Cylindrical Glands and Egg Sac Silk of Giant Wood Spider, Nephila pilipes
The “potentially repurposed by a ‘modern’ male spider” caveat in the title of one study hints at an interesting evolutionary puzzle. In at least one lineage, male spiders may have co-opted glands that are normally female-specific for new functions. This remains an area of active investigation, but the broad rule holds: egg sac silk is female business, and the glands that produce it are part of what makes the female silk toolkit more complex than the male’s.
Female Orb Weavers Recycle Their Webs Daily
For female orb weavers, web building is not a one-time construction project but a daily cycle. The majority of ecribellate orb-weaving species tear down and ingest the previous day’s web before spinning a new one.9ResearchGate. Orb web recycling in Araneus cavaticus (Araneae, Araneidae) with an emphasis on the adhesive spiral component, GABamide This recycling typically happens during the high humidity of evening or early morning, when the sticky viscous droplets on the capture spiral are fully hydrated. By eating the old web, the spider recovers both protein and water, making the daily rebuild far less wasteful than it sounds.
This cycle means that a female orb weaver’s silk glands are under constant production pressure. The glands need to produce enough silk each day to replace what was consumed, and the composition of that silk shifts across the spider’s life and molting cycle. During molting, for example, significant structural changes occur in the major ampullate gland, with certain types of secretory granules disappearing and reappearing as the spider sheds its old exoskeleton and resumes spinning.10PubMed Central. Molt-related changes in the major ampullate silk gland of the barn spider Araneus cavaticus Males, which stop building capture webs after their final molt, do not face this relentless cycle.
Sex Differences in Foraging Beyond the Web
The divergence between male and female silk use extends to foraging behavior more broadly. In Zodarion spiders, which are specialized ant hunters, the difference is stark. A field study found that most females (about 88%) and juveniles (about 81%) actively hunted ants, while only around 2% of males did so. The remaining individuals simply patrolled the ant trail without engaging in active predation.11Animal Behaviour. Sex-specific kleptoparasitic foraging in ant-eating spiders Males in this species were overwhelmingly kleptoparasites, stealing prey or scrounging rather than hunting on their own. This pattern reinforces a general theme: once male spiders reach adulthood, active foraging, whether through webs or direct hunting, takes a back seat to mate-seeking.
That does not mean adult males never eat. Wandering males will opportunistically feed when they can, and some species’ males do maintain small, reduced webs or steal from female webs. But the energy budget of a small adult male spider looks fundamentally different from a female’s. She needs to fuel egg production and daily web construction. He needs to fuel locomotion and courtship displays. Their silk use reflects those different demands.
Social Spiders and Shared Webs
The male-female split in web building gets more complicated in social spider species, where colonies share a single large web. In the Indian social spider Stegodyphus sarasinorum and the South American social spider Anelosimus eximius, researchers tested whether individuals specialize in particular tasks like web maintenance or prey capture. In A. eximius, there was no evidence of individual specialization, but adult and subadult females were more likely to attack prey than juveniles were.12PubMed. Task specialization in two social spiders, Stegodyphus sarasinorum (Eresidae) and Anelosimus eximius (Theridiidae) In these communal setups, the line between “male web” and “female web” dissolves. Everyone lives on the same structure, and task allocation is driven more by size and developmental stage than by sex alone.
Social spiders are a small minority of spider species overall, but they illustrate that the conventional narrative of “females build, males wander” is a generalization shaped by the orb weavers and cobweb spiders that dominate public awareness. In many non-web-building spider families (wolf spiders, jumping spiders, ground hunters), neither sex builds a prey-capture web, and both use silk for draglines, egg sacs, retreats, or ballooning. The question “do only females make webs?” is most meaningful within the families that actually rely on webs for food.
Why the Misconception Persists
If you picture a spider’s web, you almost certainly picture a large orb web glistening with dew, and the spider sitting at its center is almost certainly female. This is not wrong as a mental snapshot. The webs humans notice, the big ones strung across doorways and garden paths, are overwhelmingly built by females. Male webs, when they exist at all, tend to be small, short-lived, and tucked away in less conspicuous spots. Male courtship silk is invisible to anyone not watching closely with a flashlight. Sperm webs are built and discarded in minutes. Bridal veils happen during mating events that most people never witness.
Popular media reinforces the skew. Nature documentaries love to show a female black widow or golden orbweaver presiding over an enormous web, and for good reason: it is visually spectacular. The male’s contribution, a tiny mating thread vibrating imperceptibly, or a few strands of silk hastily wrapped around a female’s legs, makes for less compelling footage. The result is a public impression that web building is exclusively female territory, when the reality is that males are prolific silk users who simply channel that silk into different, less photogenic structures.
Silk Beyond the Web in Both Sexes
It is worth stepping back from the web itself, because silk serves both sexes in roles that have nothing to do with catching food. Every spider, male or female, trails a dragline behind it. This safety line anchors the spider to a surface and can arrest a fall. Spiderlings of both sexes use silk for “ballooning,” releasing threads that catch the wind and carry them to new habitats. This dispersal mechanism is shared across many families and is not sex-limited.
Both sexes also use silk to build retreats, small shelters that serve as resting places, molting chambers, or hiding spots from predators. In many ground-dwelling spiders, these retreats are the closest thing to a “web” that either sex produces, and there is no meaningful difference in how males and females construct them. The sex-specific divergence in silk use is most dramatic in families where females build elaborate prey-capture webs. In families where webs are not the primary foraging strategy, male and female silk use looks much more similar.
So the answer is not that males cannot make webs, or that they lack the physical equipment. It is that in species where web building is an energy-intensive daily commitment tied to food capture, natural selection has pushed males away from that investment and toward using their silk for reproduction instead. Females spin for dinner. Males spin for love, safety, and a chance to pass on their genes before their brief adult lives end.