Diet Termites are primarily
detritivores, consuming dead plants at any level of decomposition. They also play a vital role in the ecosystem by recycling waste material such as dead wood, faeces and plants. Many species eat
cellulose, having a specialised midgut that breaks down the fibre. Termites are considered to be a major source (11%) of
atmospheric methane, one of the prime
greenhouse gases, produced from the breakdown of cellulose. Termites rely primarily upon a symbiotic microbial community that includes bacteria and
flagellate protists, such as
metamonads and
hypermastigids. This community provides the enzymes that digests the cellulose, allowing the insects to absorb the end products for their own use. The microbial ecosystem present in the termite gut contains many species found nowhere else on Earth. Termites hatch without these symbionts present in their guts, and develop them after being fed a culture from other termites. Gut
protozoa, such as
Trichonympha, in turn, rely on symbiotic
bacteria embedded on their surfaces to produce some of the necessary
digestive enzymes. Most higher termites, especially in the family Termitidae, can produce their own
cellulase enzymes, but they rely primarily upon the bacteria. The flagellates have been lost in Termitidae. Researchers have found species of
spirochetes living in termite guts capable of fixing atmospheric nitrogen to a form usable by the insect. Judging from closely related bacterial species, it is strongly presumed that the termites' and cockroach's
gut microbiota derives from their
dictyopteran ancestors. Despite primarily consuming decaying plant material as a group, many termite species have been observed to opportunistically feed on dead animals to supplement their dietary needs. Termites are also known to harbor bacteriophages in their gut. Some of these bacteriophages likely infect the symbiotic bacteria which play a key role in termite biology. The exact role and function of bacteriophages in the termite gut microbiome is not clearly understood. Termite gut bacteriophages also show similarity to bacteriophages (
CrAssphage) found in the human gut. Certain species such as
Gnathamitermes tubiformans have seasonal food habits. For example, they may preferentially consume Red three-awn (
Aristida longiseta) during the summer, Buffalograss (
Buchloe dactyloides) from May to August, and blue grama
Bouteloua gracilis during spring, summer and autumn. Colonies of
G. tubiformans consume less food in spring than they do during autumn when their feeding activity is high. Various woods differ in their susceptibility to termite attack; the differences are attributed to such factors as moisture content, hardness, and resin and lignin content. In one study, the drywood termite
Cryptotermes brevis strongly preferred
poplar and
maple woods to other woods that were generally rejected by the termite colony. These preferences may in part have represented conditioned or learned behaviour. Some species of termite practice
fungiculture. They maintain a "garden" of specialised fungi of genus
Termitomyces, which are nourished by the excrement of the insects. When the fungi are eaten, their spores pass undamaged through the intestines of the termites to complete the cycle by germinating in the fresh faecal pellets. Molecular evidence suggests that the family
Macrotermitinae developed agriculture about 31 million years ago. It is assumed that more than 90 per cent of dry wood in the semiarid savannah ecosystems of Africa and Asia are reprocessed by these termites. Originally living in the rainforest, fungus farming allowed them to colonise the African savannah and other new environments, eventually expanding into Asia. Depending on their feeding habits, termites are placed into two groups: the lower termites and higher termites. The lower termites predominately feed on wood. As wood is difficult to digest, termites prefer to consume fungus-infected wood because it is easier to digest and the fungi are high in protein. Meanwhile, the higher termites consume a wide variety of materials, including faeces,
humus, grass, leaves and roots. The gut of the lower termites contains many species of bacteria along with
protozoa and
Holomastigotoides, while the higher termites only have a few species of bacteria with no protozoa.
Predators with a captured alate Termites are consumed by a wide variety of
predators. One termite species alone,
Hodotermes mossambicus, was reported (1990) in the stomach contents of 65
birds and 19
mammals.
Arthropods such as
ants,
centipedes,
cockroaches,
crickets,
dragonflies,
scorpions and
spiders,
reptiles such as
lizards, and
amphibians such as
frogs and
toads consume termites, with two
spiders in the family
Ammoxenidae being specialist termite predators. Other predators include
aardvarks,
aardwolves,
anteaters,
bats,
bears,
bilbies, many
birds,
echidnas,
foxes,
galagos,
numbats,
mice and
pangolins. The
aardwolf is an
insectivorous mammal that primarily feeds on termites; it locates its food by sound and also by detecting the scent secreted by the soldiers; a single aardwolf is capable of consuming thousands of termites in a single night by using its long, sticky tongue.
Sloth bears break open mounds to consume the nestmates, while
chimpanzees have
developed tools to "fish" termites from their nest. Wear pattern analysis of bone tools used by the early
hominin Paranthropus robustus suggests that they used these tools to dig into termite mounds. Among all predators, ants are the greatest enemy to termites.
Paltothyreus tarsatus is another termite-raiding species, with each individual stacking as many termites as possible in its
mandibles before returning home, all the while recruiting additional nestmates to the raiding site through chemical trails.
Centromyrmex and
Iridomyrmex colonies sometimes nest in
termite mounds, and so the termites are preyed on by these ants. No evidence for any kind of relationship (other than a predatory one) is known. Other ants, including
Acanthostichus,
Camponotus,
Crematogaster,
Cylindromyrmex,
Leptogenys,
Odontomachus,
Ophthalmopone,
Pachycondyla,
Rhytidoponera,
Solenopsis and
Wasmannia, also prey on termites. Specialized subterranean species of army ants such as ones in the genus
Dorylus are known to commonly predate on young
Macrotermes colonies. Ants are not the only invertebrates that perform raids. Many
sphecoid wasps and several species including
Polybia and
Angiopolybia are known to raid termite mounds during the termites' nuptial flight.
Parasites, pathogens, and viruses Termites are less likely to be attacked by parasites than bees, wasps and ants, as they are usually well protected in their mounds. Nevertheless, termites are infected by a variety of parasites. Some of these include dipteran flies,
Pyemotes mites, and a large number of
nematode parasites. Most nematode parasites are in the order
Rhabditida; others are in the genus
Mermis,
Diplogaster aerivora and
Harteria gallinarum. Under imminent threat of an attack by parasites, a colony may migrate to a new location. Certain fungal pathogens such as
Aspergillus nomius and
Metarhizium anisopliae are, however, major threats to a termite colony as they are not host-specific and may infect large portions of the colony; transmission usually occurs via direct physical contact.
M. anisopliae is known to weaken the termite immune system. Infection with
A. nomius only occurs when a colony is under great stress. Over 34 fungal species are known to live as parasites on the exoskeleton of termites, with many being host-specific and only causing indirect harm to their host. Termites are infected by viruses including
Entomopoxvirinae and the
Nuclear Polyhedrosis Virus.
Locomotion and foraging Because the worker and soldier castes lack wings and thus never fly, and the reproductives use their wings for just a brief amount of time, termites predominantly rely upon their legs to move about. Foraging behaviour depends on the type of termite. For example, certain species feed on the wood structures they inhabit, and others harvest food that is near the nest. Most workers are rarely found out in the open, and do not forage unprotected; they rely on sheeting and runways to protect them from predators. Subterranean termites construct tunnels and galleries to look for food, and workers who manage to find food sources recruit additional nestmates by depositing a phagostimulant pheromone that attracts workers. Foraging workers use semiochemicals to communicate with each other, In one species,
Nasutitermes costalis, there are three phases in a foraging expedition: first, soldiers scout an area. When they find a food source, they communicate to other soldiers and a small force of workers starts to emerge. In the second phase, workers appear in large numbers at the site. The third phase is marked by a decrease in the number of soldiers present and an increase in the number of workers. Isolated termite workers may engage in
Lévy flight behaviour as an optimised strategy for finding their nestmates or foraging for food.
Competition Competition between two colonies always results in
agonistic behaviour towards each other, resulting in fights. These fights can cause mortality on both sides and, in some cases, the gain or loss of territory. "Cemetery pits" may be present, where the bodies of dead termites are buried. Studies show that when termites encounter each other in foraging areas, some of the termites deliberately block passages to prevent other termites from entering. Dead termites from other colonies found in exploratory tunnels leads to the isolation of the area and thus the need to construct new tunnels. Conflict between two competitors does not always occur. For example, though they might block each other's passages, colonies of
Macrotermes bellicosus and
Macrotermes subhyalinus are not always aggressive towards each other. Suicide cramming is known in
Coptotermes formosanus. Since
C. formosanus colonies may get into physical conflict, some termites squeeze tightly into foraging tunnels and die, successfully blocking the tunnel and ending all agonistic activities. Among the reproductive caste, neotenic queens may compete with each other to become the dominant queen when there are no primary reproductives. This struggle among the queens leads to the elimination of all but a single queen, which, with the king, takes over the colony. Ants and termites may compete with each other for nesting space. In particular, ants that prey on termites usually have a negative impact on arboreal nesting species.
Communication Most termites are blind, so communication primarily occurs through chemical, mechanical and pheromonal cues. These methods of communication are used in a variety of activities, including foraging, locating reproductives, construction of nests, recognition of nestmates, nuptial flight, locating and fighting enemies, and defending the nests. When termites construct their nests, they use predominantly indirect communication. No single termite would be in charge of any particular construction project. Individual termites react rather than think, but at a group level, they exhibit a sort of collective cognition. Specific structures or other objects such as pellets of soil or pillars cause termites to start building. The termite adds these objects onto existing structures, and such behaviour encourages building behaviour in other workers. The result is a self-organised process whereby the information that directs termite activity results from changes in the environment rather than from direct contact among individuals. Each colony has its own distinct odour. This odour is a result of genetic and environmental factors such as the termites' diet and the composition of the bacteria within the termites' intestines.
Defence Termites rely on alarm communication to defend a colony. Other methods of defence include headbanging and secretion of fluids from the frontal gland and defecating faeces containing alarm pheromones. In some species, some soldiers block tunnels to prevent their enemies from entering the nest, and they may deliberately rupture themselves as an act of defence. In cases where the intrusion is coming from a breach that is larger than the soldier's head, soldiers form a
phalanx-like formation around the breach and bite at intruders. To termites, any breach of their tunnels or nests is a cause for alarm. When termites detect a potential breach, the soldiers usually bang their heads, apparently to attract other soldiers for defence and to recruit additional workers to repair any breach. Nasutes have lost their mandibles through the course of evolution and must be fed by workers. Similarly,
Formosan subterranean termites have been known to secrete
naphthalene to protect their nests. Soldiers of the species
Globitermes sulphureus commit suicide by
autothysis – rupturing a large gland just beneath the surface of their cuticles. The thick, yellow fluid in the gland becomes very sticky on contact with the air, entangling ants or other insects that are trying to invade the nest. Another termite,
Neocapriterme taracua, also engages in suicidal defence. Workers physically unable to use their mandibles while in a fight form a pouch full of chemicals, then deliberately rupture themselves, releasing toxic chemicals that paralyse and kill their enemies. The soldiers of the
neotropical termite family
Serritermitidae have a defence strategy which involves front gland autothysis, with the body rupturing between the head and abdomen. When soldiers guarding nest entrances are attacked by intruders, they engage in autothysis, creating a block that denies entry to any attacker. Workers use several different strategies to deal with their dead, including burying, cannibalism, and avoiding a corpse altogether. To avoid
pathogens, termites occasionally engage in
necrophoresis, in which a nestmate carries away a corpse from the colony to dispose of it elsewhere. Which strategy is used depends on the nature of the corpse a worker is dealing with (i.e. the age of the carcass). This fungus mimics these eggs by producing cellulose-digesting enzymes known as
glucosidases. A unique mimicking behaviour exists between various species of
Trichopsenius beetles and certain termite species within
Reticulitermes. The beetles share the same
cuticle hydrocarbons as the termites and even biosynthesize them. This chemical mimicry allows the beetles to integrate themselves within the termite colonies. The developed
appendages on the physogastric abdomen of
Austrospirachtha mimetes allows the beetle to mimic a termite worker. Some ant species are known to capture termites to use as a fresh food source later on, rather than killing them. For example,
Formica nigra captures termites, and those that try to escape are immediately seized and driven underground. Certain species of ants in the subfamily
Ponerinae conduct these raids although other ant species go in alone to steal the eggs or nymphs. Despite this, some termites and ants can coexist peacefully and mutually benefit from cohabitation. Some species of termite, including
Nasutitermes corniger, form associations with certain ant species to keep away predatory ant species. The earliest known association between
Azteca ants and
Nasutitermes termites date back to the Oligocene to Miocene period. 54 species of ants are known to inhabit
Nasutitermes mounds, both occupied and abandoned ones. One reason many ants live in
Nasutitermes mounds is due to the termites' frequent occurrence in their geographical range; another is to protect themselves from floods.
Iridomyrmex also inhabits termite mounds although no evidence for any kind of relationship (other than a predatory one) is known. Some invertebrate organisms such as beetles, caterpillars, flies and millipedes are termitophiles and dwell inside termite colonies (they are unable to survive independently). so are regarded as potential pollinators for a number of flowering plants. One flower in particular,
Rhizanthella gardneri, is regularly pollinated by foraging workers, and it is perhaps the only
Orchidaceae flower in the world to be pollinated by termites. Defence is typically achieved by secreting antifeedant chemicals into the woody cell walls. An extract of a species of Australian false sandalwood,
Eremophila mitchellii, has been shown to repel termites; tests have shown that termites are strongly repelled by the toxic material to the extent that they will starve rather than consume the food. When kept close to the extract, they become disoriented and eventually die. A total of 26 species of termites were present in the three sites, and 196 encounters were recorded in the transects. The termite assemblages were considerably different among sites, with a conspicuous reduction in both diversity and abundance with increased disturbance, related to the reduction of tree density and soil cover, and with the intensity of trampling by cattle and goats. The wood-feeders were the most severely affected feeding group. ==Nests==