Some ants and termites do share the same nest, and the arrangement is far more common in the tropics than most people realize. The relationship runs a wide spectrum: certain ant species move into termite mounds as welcome guests that help defend the colony, while others infiltrate as parasites or outright predators. A neotropical termite called Nasutitermes corniger is one of the best-studied examples, cohabiting with multiple ant species in a relationship where nutrients actually flow in both directions.
How Ants and Termites End Up in the Same Nest
The most thoroughly documented cases of ant-termite cohabitation come from tropical environments, where termite mounds are large, structurally complex, and thermally stable. These mounds are valuable real estate. Ants looking for shelter, especially during rainy seasons, sometimes move into vacant or peripheral chambers of an active termite nest rather than building their own from scratch. In the case of Nasutitermes corniger, a common termite across Central and South America, researchers found that various ant species use part of the termite nest as shelter during the wet season.1Annals of the Entomological Society of America. Trophic Interactions Between Ants and Termites that Share Common Nests The arrangement is not random: termites tolerate certain ant species more than others, and the frequency of cohabitation appears to vary with how much predation risk a given ant species poses.
What makes this interesting is that the relationship can be genuinely two-sided. Using radioactive tracers, researchers demonstrated that nutrients flow from ants to termites and from termites to ants. The ants may prey on live or dead termite workers, but in doing so they also provide nitrogen-rich waste products that the termite colony can use.1Annals of the Entomological Society of America. Trophic Interactions Between Ants and Termites that Share Common Nests That bidirectional nutrient exchange blurs the line between parasitism and mutualism in ways that make the relationship hard to categorize neatly.
When Sharing a Nest Benefits Both Sides
In some cases, the arrangement tips clearly toward mutualism. In Australia, researchers studying termite mounds found that two species of Camponotus ants were heavily dependent on termite mounds for their own nest sites. These ants did not just passively occupy spare chambers. They actively defended the termite mound against attacks by meat ants, one of the most aggressive and destructive ant groups on the continent. Termite colonies that cohabited with these Camponotus ants were notably vigorous, suggesting the defense the ants provided had a real payoff for the termites.2PubMed. Defense of termitaria by termitophilous ants
The logic is straightforward once you see it from the termites’ perspective. Termite soldiers are effective at many things, but warding off large, fast-moving ant species that arrive in massive numbers is not always one of them. Having a resident ant colony that will fight off those raiders is like hiring a bodyguard by offering a spare room. The ants get a ready-made, climate-controlled nest and access to food; the termites get a standing army against their worst enemies. Of the eight ant species found living in the termite mounds in that study, only two provided this kind of meaningful defense. The rest were more exploitative, taking shelter without contributing much in return.
The More Common Story Is Predation
For every case of genuine cohabitation, there are many more where ants are simply hunting termites. Ants are widely considered the most fierce and important predators termites face, and some ant species have evolved extraordinarily specialized behaviors to exploit them.
The African ant Megaponera analis is perhaps the most dramatic example. This species feeds exclusively on termites of the subfamily Macrotermitinae, the group that includes the large mound-building termites across sub-Saharan Africa. Megaponera scouts search the landscape for termite foraging sites, then return to their own colony and lead highly organized raid columns to the location.3PubMed. Time-optimized path choice in the termite-hunting ant Megaponera analis These raids are not casual. The ants march in formation, attack en masse, and carry captured termites back to their nest. The battles can be violent enough that the ants sustain injuries, and researchers have documented that Megaponera workers will rescue injured nestmates from the battlefield and carry them home to recover.4PubMed Central. Saving the injured: Rescue behavior in the termite-hunting ant Megaponera analis
This is not cohabitation. The ants live in their own nests and go to war against termite colonies at their feeding grounds. But it illustrates the evolutionary pressure that makes genuine cohabitation so surprising: ants are, as a rule, termite enemies. The species that manage to live inside a termite mound peacefully are the exceptions, and they have likely evolved specific chemical or behavioral traits that keep the termites from treating them as invaders.
How Termites Fight Back
Termites have not taken the threat from ants lying down. Many termite species have evolved soldier castes with specialized weaponry, and some of those weapons are tuned specifically for ant defense. Nasute termites, a large group found across the tropics, have soldiers with nozzle-shaped heads that spray a sticky, toxic secretion at attackers. In Nasutitermes costalis, these soldiers go further than just defending the nest entrance. They actually serve as scouts, exploring new terrain ahead of foraging workers and laying chemical trails to recruit more soldiers before any workers venture out.5PubMed Central. Enemy deterrence in the recruitment strategy of a termite: Soldier-organized foraging in Nasutitermes costalis
This soldier-first foraging strategy is unusual among social insects. In most termite species, workers lead and soldiers accompany. In N. costalis, the soldiers effectively clear the way, and the foraging column does not emerge until the pheromone concentration reaches a threshold that signals safety. The entire system appears to be an anti-ant defense. Ants are ambush predators of termite foraging columns: they detect the columns, swarm them, and carry off workers. By sending soldiers ahead in large numbers first, N. costalis makes the initial contact point heavily defended rather than vulnerable.
The existence of such elaborate countermeasures hints at how intense the evolutionary arms race between ants and termites has been. Termites that cohabit with certain ant species may be, in a sense, the ones that found a way to turn the arms race into a truce with specific partners while continuing to defend against all others.
Fossil Evidence That This Relationship Is Ancient
Ant-termite interactions are not a recent ecological development. A piece of amber from the Dominican Republic, dating to the late Oligocene or middle Miocene period, preserved the first known fossil showing ants and termites together in the same snapshot. The amber contained Azteca ants alongside Nasutitermes termites, the same two groups that cohabit today in the neotropics. In the same piece of amber, a Neivamyrmex army ant was preserved clutching a termite worker between its jaws, and another termite had a visibly bitten abdomen.6PLOS ONE. The First Ant-Termite Syninclusion in Amber with CT-Scan Analysis of Taphonomy
This single piece of amber captured both sides of the ant-termite relationship: possible cohabitation between Azteca and Nasutitermes, and active predation by army ants. The finding suggests that the modern spectrum of ant-termite relationships, from mutualism to raiding, has roots stretching back at least 15 to 20 million years. The same ecological dynamics we observe in living colonies today were apparently already playing out in Central American forests during the Miocene.
The researchers noted that the Azteca–Nasutitermes association, though well known among tropical entomologists, is poorly documented in the scientific literature.7PLOS ONE. The First Ant-Termite Syninclusion in Amber with CT-Scan Analysis of Taphonomy – Section: Discussion Finding it preserved in amber gave it a minimum age and a kind of paleontological credibility that field observations alone had not fully established.
Why It Matters for Ecosystems
The interplay between ants and termites has consequences well beyond the walls of a single mound. Both groups are ecosystem engineers: they dig tunnels, move soil, and cycle nutrients. When they interact, the effects on the surrounding environment can be substantial.
In agricultural settings, the combined activity of ants and termites can boost crop production. A field experiment in a dry-climate wheat farm showed that ants and termites increased wheat yield by roughly 36 percent. The mechanism was not chemical fertilization in any direct sense but physical: the tunnels both insects dug improved soil water infiltration and helped nitrogen move deeper into the root zone.8PubMed Central. Ants and termites increase crop yield in a dry climate In arid environments where water is the limiting factor for plant growth, that tunneling is enormously valuable. The fact that the two insect groups were contributing together, rather than one canceling out the other, suggests that in some landscapes their combined presence is more beneficial than either alone.
But the relationship is not always additive. In a study examining wood decomposition, termite activity was the strongest driver of how quickly dead wood broke down, with mass loss increasing about 20 percent for every doubling of termite activity. Yet ant abundance, which rose under warmer experimental conditions, appeared to limit termite activity. As ant populations grew, termite activity dropped, and with it, the rate of wood decomposition.9PubMed. Antagonistic biotic interactions mitigate the positive effects of warming on wood decomposition In other words, ants were indirectly slowing down nutrient cycling by suppressing the termites that do much of the work.
This tension has real implications for how ecosystems respond to climate change. Warmer temperatures generally favor both groups, but if warming disproportionately benefits ants, and those ants suppress termites, the net effect on processes like decomposition could be the opposite of what a simple “warmer equals faster” model would predict. The ant-termite dynamic acts as a kind of ecological thermostat, buffering the system against runaway change.
What Happens Inside Your House Is a Different Story
If you have found both ants and termites in or around your home, you might wonder whether they are cohabiting or fighting. The answer, almost always, is neither in the mutualistic sense described above. The species involved in documented cohabitation are tropical, and the relationships depend on the specific biology of particular termite and ant lineages. The ants and termites you encounter in a North American or European home are overwhelmingly in competition for the same resources or simply occupying separate niches in the same structure.
Carpenter ants and subterranean termites, for instance, are both attracted to damp wood, but they do not share it cooperatively. Carpenter ants excavate galleries for nesting but do not eat the wood; termites consume it. When both are present in the same building, they tend to occupy different zones and avoid each other. There are anecdotal reports of carpenter ants preying on termites when they encounter them, but this is opportunistic predation, not a structured relationship.
Pest control professionals sometimes find both species during an inspection and assume one attracts the other. The reality is simpler: both are drawn to the same conditions, particularly moisture-damaged wood. Finding both does not mean they are cooperating, and treating one does not eliminate the other. They require separate management strategies.
Why the Science Is Thinner Than You Would Expect
Given how common both ants and termites are, and how frequently they interact, the scientific literature on their shared-nest relationships is surprisingly sparse. The amber fossil study explicitly flagged the Azteca–Nasutitermes association as “poorly documented” despite being well known to field researchers.7PLOS ONE. The First Ant-Termite Syninclusion in Amber with CT-Scan Analysis of Taphonomy – Section: Discussion Part of the problem is logistical: studying what happens inside an active termite mound without destroying the mound is difficult. Termite nests are structurally complex, often extending deep underground, and the insects seal breaches quickly. Observing natural behavior requires either long-term non-invasive monitoring or laboratory colonies that may not replicate the conditions that drive cohabitation in the field.
Another factor is disciplinary fragmentation. Ant researchers and termite researchers tend to work in separate communities, attend different conferences, and publish in different journals. The interactions between the two groups fall into a gap between specialties. When ant ecologists study ant foraging, the termites are prey items. When termite ecologists study mound defense, the ants are threats. The mutualistic middle ground, where both groups benefit, gets less attention because it does not fit cleanly into either narrative.
The radioactive tracer work on Nasutitermes corniger remains one of the few studies to directly demonstrate bidirectional nutrient transfer between cohabiting ants and termites.1Annals of the Entomological Society of America. Trophic Interactions Between Ants and Termites that Share Common Nests That study was published in 1995, and the field has not produced many comparable experiments since. Most of what we know about these relationships still comes from observational field notes rather than controlled experiments, which means the mechanisms behind cohabitation tolerance, nutrient exchange pathways, and the chemical signals that prevent host-guest aggression remain largely unexplored. For two of the most abundant insect groups on earth, that gap is striking.