Termites are a group of detritivore Eusociality which consume a variety of Detritus, generally in the form of wood, Plant litter, and Humus. They are distinguished by their moniliform antennae and the soft-bodied, unpigmented worker caste for which they have been commonly termed " white ants"; however, they are not but highly derived cockroaches. About 2,997 extant species are currently described, 2,125 of which are members of the family Termitidae.
Termites comprise the infraorder Isoptera, or alternatively the epifamily Termitoidae, within the order Blattodea (the ). Termites were once classified in a separate order from cockroaches, but recent phylogenetic studies indicate that they evolved from cockroaches, as they are deeply nested within the group, and the sister group to wood-eating cockroaches of the genus Cryptocercus. Previous estimates suggested the divergence took place during the Jurassic or Triassic. More recent estimates suggest that they have an origin during the Late Jurassic, with the first fossil records in the Early Cretaceous.
Similarly to ants and some and from the separate order Hymenoptera, most termites have an analogous "worker" and "soldier" caste system consisting of mostly sterile individuals which are physically and behaviorally distinct. Unlike ants, most colonies begin from sexually mature individuals known as the "king" and "queen" that together form a lifelong monogamous pair. Also unlike ants, which undergo a complete metamorphosis, termites undergo an incomplete metamorphosis that proceeds through egg, nymph, and Imago stages. Termite colonies are commonly described as due to the collective behaviors of the individuals which form a self-governing entity: the colony itself. Their colonies range in size from a few hundred individuals to enormous societies with several million individuals. Most species are rarely seen, having a cryptic life history where they remain hidden within the galleries and tunnels of their nests for most of their lives.
Termites' success as a group has led to them colonizing almost every global landmass, with the highest diversity occurring in the tropics where they are estimated to constitute 10% of the animal biomass, particularly in Africa which has the richest diversity with more than 1000 described species. They are important decomposers of decaying plant matter in the Subtropics and Tropics regions of the world, and their recycling of wood and plant matter is of considerable ecological importance. Many species are ecosystem engineers capable of altering soil characteristics such as hydrology, decomposition, nutrient cycling, vegetative growth, and consequently surrounding biodiversity through the large Termite mound constructed by certain species.
Termites have several impacts on humans. They are a delicacy in the diet of some human cultures such as the Makiritare in the Alto Orinoco province of Venezuela, where they are commonly used as a spice. They are also used in traditional medicinal treatments of various diseases and ailments, such as influenza, asthma, bronchitis, etc. Termites are most famous for being structural pests; however, the vast majority of termite species are innocuous, with the regional numbers of economically significant species being: North America, 9; Australia, 16; Indian subcontinent, 26; tropical Africa, 24; Central America and the West Indies, 17. Of known pest species, 28 of the most invasive and structurally damaging belong to the genus Coptotermes. The distribution of most known pest species is expected to increase over time as a consequence of climate change. Increased urbanization and connectivity is also predicted to expand the range of some pest termites.
The oldest unambiguous termite fossils date to the early Cretaceous, but given the diversity of Cretaceous termites and early fossil records showing mutualism between microorganisms and these insects, they possibly originated earlier in the Jurassic or Triassic. Possible evidence of a Jurassic origin is the assumption that the extinct Mammaliaformes Fruitafossor from Morrison Formation consumed termites, judging from its morphological similarity to modern termite-eating mammals. Morrison Formation also yields social insect nest fossils close to that of termites. The oldest termite nest discovered is believed to be from the Upper Cretaceous in West Texas, where the oldest known faecal pellets were also discovered. Claims that termites emerged earlier have faced controversy. For example, F. M. Weesner indicated that the Mastotermitidae termites may go back to the Late Permian, 251 million years ago, and fossil wings that have a close resemblance to the wings of Mastotermes of the Mastotermitidae, the most primitive living termite, have been discovered in the Permian layers in Kansas. It is even possible that the first termites emerged during the Carboniferous.
External phylogeny showing relationship of termites with other insect groups:
Internal phylogeny showing relationship of extant termite families:
There are currently 3,173 living and fossil termite species recognised, classified in 12 families; reproductive and/or soldier castes are usually required for identification. The infraorder Isoptera is divided into the following clade and family groups, showing the subfamilies in their respective classification:Constantino, Reginaldo; Termite taxonomist authority, University of Brazil: http://164.41.140.9/catal/statistics.php?filtro=fossil
http://164.41.140.9/catal/statistics.php?filtro=extant
Total: 3,173 extant and extinct sp in Catalogue
http://www.pesquisar.unb.br/professor/reginaldo-constantino
Due to their soft cuticles, termites do not inhabit cool or cold habitats. There are three ecological groups of termites: dampwood, drywood and subterranean. Dampwood termites are found only in coniferous forests, and drywood termites are found in hardwood forests; subterranean termites live in widely diverse areas. One species in the drywood group is the West Indian drywood termite (Cryptotermes brevis), which is an invasive species in Australia.
Most worker and soldier termites are completely blind as they do not have a pair of eyes. However, some species, such as Hodotermes, have compound eyes which they use for orientation and to distinguish sunlight from moonlight. The (winged males and females) have eyes along with lateral ocelli. Lateral ocelli, however, are not found in all termites, absent in the families Hodotermitidae, Termopsidae, and Archotermopsidae. Like other insects, termites have a small tongue-shaped labrum and a clypeus; the clypeus is divided into a postclypeus and anteclypeus. Termite antennae have a number of functions such as the sensing of touch, taste, odours (including pheromones), heat and vibration. The three basic segments of a termite antenna include a scape, a pedicel (typically shorter than the scape), and the flagellum (all segments beyond the scape and pedicel). The mouth parts contain a maxillae, a labium, and a set of mandibles. The maxillae and labium have Pedipalp that help termites sense food and handling. The cuticle of most castes is soft and flexible due to a resulting lack of sclerotization, particularly of the abdomen which often appears translucent. Pigmentation and sclerotization of the cuticle correlates with life history, with species that spend more time in the surface in the open tending to have a more sclerotized and pigmented exoskeleton.
Consistent with all insects, the anatomy of the termite thorax consists of three segments: the prothorax, the mesothorax and the metathorax. Each segment contains a pair of Arthropod leg. On alates, the wings are located at the mesothorax and metathorax, which is consistent with all four-winged insects. The mesothorax and metathorax have well-developed exoskeletal plates; the prothorax has smaller plates.
Termites have a ten-segmented abdomen with two plates, the Tergum and the sternites. The tenth abdominal segment has a pair of short Cercus. There are ten tergites, of which nine are wide and one is elongated. The reproductive organs are similar to those in cockroaches but are more simplified. For example, the intromittent organ is not present in male alates, and the sperm is either immotile or aflagellate. However, Mastotermitidae termites have multiflagellate sperm with limited motility. The genitals in females are also simplified. Unlike in other termites, Mastotermitidae females have an ovipositor, a feature strikingly similar to that in female cockroaches.
The non-reproductive castes of termites are wingless and rely exclusively on their six legs for locomotion. The alates fly only for a brief amount of time, so they also rely on their legs. The appearance of the legs is similar in each caste, but the soldiers have larger and heavier legs. The structure of the legs is consistent with other insects: the parts of a leg include a coxa, trochanter, femur, tibia and the tarsus. The number of tibial spurs on an individual's leg varies. Some species of termite have an arolium, located between the claws, which is present in species that climb on smooth surfaces but is absent in most termites.
Unlike in ants, the hind-wings and fore-wings are of equal length. Most of the time, the alates are poor flyers; their technique is to launch themselves in the air and fly in a random direction. Studies show that in comparison to larger termites, smaller termites cannot fly long distances. When a termite is in flight, its wings remain at a right angle, and when the termite is at rest, its wings remain parallel to the body.
The developmental plasticity in termites can be described similarly to cell potency, where each molt offers a varying level of phenotypic potency. Early instars typically exhibit the highest phenotypic potency and can be described as totipotent, able to molt into all alternative phenotypes. Following instars can be pluripotent, being able to molt into reproductives and non-reproductives but cannot molt into at least one phenotype. Multipotent instars are able to molt into either reproductive or non-reproductive phenotypes. Unipotent instars are able to molt into developmentally close phenotypes, and then the final instar is committed, being no longer able to change phenotype and so are functionally an adult. In most termites, phenotypic potency decreases with every successive molt. Notable exceptions are basal taxa such as the Archotermopsidae, which are able to retain high developmental plasticity even up to the late instars. In these basal taxa, the immatures are able to go through progressive ( nymph-to-imago), regressive ( winged-to-wingless) and stationary ( size increase, remains wingless) molts, which typically indicates the developmental trajectory an individual follows.
There is significant variation of the developmental patterns in termites even across closely related taxa, but can typically be generalized into the following two patterns: The first is the linear developmental pathway, where all immatures are capable of developing into winged adults ( ), exhibit high phenotypic potency, and where there exists no true sterile caste other than the soldier. The second is the bifurcated developmental pathway, where immatures diverge into two distinct developmental lineages known as the nymphal (winged) and apterous (wingless) lines. The bifurcation occurs early, either at the egg or the first two instars, and represents an irreversible and committed development to either the reproductive or non-reproductive lifestyles. As such, the apterous lineage consists mostly of wingless and truly altruistic sterile individuals (true workers, soldiers), whereas the nymphal lineage consists mainly of fertile individuals destined to become winged reproductives. The bifurcated developmental pathway is found mainly in the derived taxa (i.e. Neoisoptera), and is believed to have evolved in tandem with the sterile worker caste as species moved to foraging for food beyond their nests, as opposed to the nest also being the food (such as in obligate wood-dwellers).
There are three main castes which are discussed below:
Worker termites undertake the most labor within the colony, being responsible for foraging, food storage, and brood and nest maintenance. Workers are tasked with the digestion of cellulose in food and are thus the most likely caste to be found in infested wood. The process of worker termites feeding other nestmates is known as trophallaxis. Trophallaxis is an effective nutritional tactic to convert and recycle nitrogenous components. It frees the parents from feeding all but the first generation of offspring, allowing for the group to grow much larger and ensuring that the necessary gut symbionts are transferred from one generation to another. Workers are believed to have evolved from older wingless immatures ( Larvae) that evolved cooperative behaviors; and indeed in some basal Taxon the late instar larvae are known to undertake the role of workers without differentiating as a true separate caste. Workers can either be male or female, although in some species with polymorphic workers either sex may be restricted to a certain developmental path. Workers may also be fertile or sterile, however the term "worker" is normally reserved for the latter, having evolved in taxa that exhibit a bifurcated developmental pathway. As a result, sterile workers like in the family Termitidae are termed true workers and are the most derived, while those that are undifferentiated and fertile as in the wood-nesting Archotermopsidae are termed pseudergates, which are the most basal. True workers are individuals which irreversibly develop from the apterous lineage and have completely forgone development into a winged adult. They display altruistic behaviors and either have terminal molts or exhibit a low level of phenotypical potency. True workers across different termite taxa ( Mastotermitidae, Hodotermitidae, Rhinotermitidae & Termitidae) can widely vary in the level of developmental plasticity even between closely related taxa, with many species having true workers that can molt into the other apterous castes such as (worker reproductive; apterous neotenics), soldiers, or the other worker castes. Pseudergates sensu stricto are individuals which arise from the linear developmental pathway that have regressively molted and lost their wing buds, and are regarded as totipotent immatures. They are capable of performing work but are overall less involved in labor and considered more cooperative than truly altruistic. Pseudergates sensu lato, otherwise known as false workers, are most represented in basal lineages ( Kalotermitidae, Archotermopsidae, Hodotermopsidae, Serritermitidae) and closely resemble true workers in which they also perform most of the work and are similarly altruistic, however differ in developing from the linear developmental pathway where they exist in a stationary molt; i.e they have halted development before the growth of wing buds, and are regarded as pluripotent immatures.
The soldier caste is the most anatomically and behaviorally specialized, and their sole purpose is to defend the colony. Many soldiers have large heads with highly modified powerful jaws so enlarged that they cannot feed themselves. Instead, like juveniles, they are fed by workers. , simple holes in the forehead that lead to a gland which exudes defensive secretions, are a feature of the clade Neoisoptera and are present in all extant taxa such as Rhinotermitidae.
The primary reproductive caste of a colony consists of the fertile adult ( imago) female and male individuals, colloquially known as the queen and king. The queen of the colony is responsible for egg production of the colony. Unlike in ants, the male and female reproductives form lifelong pairs where the king will continue to mate with the queen throughout their lives. In some species, the abdomen of the queen swells up dramatically to increase fecundity, a characteristic known as physogastrism. Depending on the species, the queen starts producing reproductive alates at a certain time of the year, and huge swarms emerge from the colony when nuptial flight begins. These swarms attract a wide variety of predators. The queens can be particularly long-lived for insects, with some reportedly living as long as 30 or 50 years. In both the linear and bifurcated developmental pathways, the primary reproductives only develop from winged immatures (nymphs). These winged immatures are capable of regressively molting into a form known as brachypterous neotenics ( nymphoids), which retain juvenile and adult characteristics. BN
The life cycle of a termite begins with an egg, but is different from that of a bee or ant in that it goes through a developmental process called incomplete metamorphosis, going through multiple gradual pre-adult molts that are highly developmentally plastic before becoming an adult. Unlike in other Hemimetabolism insects, nymphs are more strictly defined in termites as immature young with visible wing buds, which often invariably go through a series of Moulting to become winged Imago. Larvae, which are defined as early nymph instars with absent wing buds, exhibit the highest developmental potentiality and are able to molt into Alates, Soldiers, Neotenics, or Workers. Workers are believed to have evolved from larvae, sharing many similarities to the extent that workers can be regarded as "larval", in that both lack wings, eyes, and functional reproductive organs while maintaining varying levels of developmental flexibility, although usually to a much lesser extent in workers. The main distinction being that while larvae are wholly dependent on other nestmates to survive, workers are independent and are able to feed themselves and contribute to the colony. Workers remain wingless and across many Taxon become developmentally arrested, appearing to not change into any other caste until death. In some basal taxa, there is no distinction, with the "workers" (pseudergates) essentially being late instar larvae that retain the ability to change into all other castes.
The development of larvae into adults can take months; the time period depends on food availability and nutrition, temperature, and the size of the colony. Since larvae and nymphs are unable to feed themselves, workers must feed them, but workers also take part in the social life of the colony and have certain other tasks to accomplish such as foraging, building or maintaining the nest or tending to the queen. Pheromones regulate the caste system in termite colonies, preventing all but a very few of the termites from becoming fertile queens.
Queens of the eusociality termite Reticulitermes speratus are capable of a long lifespan without sacrificing fecundity. These long-lived queens have a significantly lower level of oxidative damage, including DNA oxidation, than workers, soldiers and nymphs. The lower levels of damage appear to be due to increased catalase, an enzyme that protects against oxidative stress.
The queen only lays 10–20 eggs in the very early stages of the colony, but lays as many as 1,000 a day when the colony is several years old. At maturity, a primary queen has a great capacity to lay eggs. In some species, the mature queen has a greatly distended abdomen and may produce 40,000 eggs a day. The two mature ovaries may have some 2,000 each. The abdomen increases the queen's body length to several times more than before mating and reduces her ability to move freely; attendant workers provide assistance.
'' workers in a nursery cell]]The king grows only slightly larger after initial mating and continues to mate with the queen for life (a termite queen can live between 30 and 50 years); this is very different from ant colonies, in which a queen mates once with the males and stores the gametes for life, as the male ants die shortly after mating. If a queen is absent, a termite king produces pheromones which encourage the development of replacement termite queens. As the queen and king are monogamous, sperm competition does not occur.
Termites going through incomplete metamorphosis on the path to becoming alates form a subcaste in certain species of termite, functioning as potential supplementary reproductives. These supplementary reproductives only mature into primary reproductives upon the death of a king or queen, or when the primary reproductives are separated from the colony. Supplementaries have the ability to replace a dead primary reproductive, and there may also be more than a single supplementary within a colony. Some queens have the ability to switch from sexual reproduction to asexual reproduction. Studies show that while termite queens mate with the king to produce colony workers, the queens reproduce their replacements (Neoteny queens) Parthenogenesis.
The neotropical termite Embiratermes neotenicus and several other related species produce colonies that contain a primary king accompanied by a primary queen or by up to 200 neoteny queens that had originated through thelytoky of a founding primary queen. The form of parthenogenesis likely employed maintains zygosity in the passage of the genome from mother to daughter, thus avoiding inbreeding depression.
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 Populus 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.
Among all predators, ants are the greatest enemy to termites. Some ant genera are specialist predators of termites. For example, Megaponera is a strictly termite-eating (termitophagous) genus that perform raiding activities, some lasting several hours. Paltothyreus 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. The Malaysian basicerotine ants Eurhopalothrix uses a different strategy of termite hunting by pressing themselves into tight spaces, as they hunt through rotting wood housing termite colonies. Once inside, the ants seize their prey by using their short but sharp mandibles. Tetramorium is a specialised predator species that feeds on small termites. A scout recruits 10–30 workers to an area where termites are present, killing them by immobilising them with their stinger. Centromyrmex and Iridomyrmex colonies sometimes nest in , 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, Fire ant 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 Spheciformes and several species including Polybia and Angiopolybia are known to raid termite mounds during the termites' nuptial flight.
Termites are infected by viruses including Entomopoxvirinae and the Nuclear Polyhedrosis Virus.
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.
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.
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.
Termites can distinguish nestmates and non-nestmates through chemical communication and gut symbionts: chemicals consisting of hydrocarbons released from the cuticle allow the recognition of alien termite species. 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.
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.
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. Additionally, an alarmed termite bumps into other termites which causes them to be alarmed and to leave pheromone trails to the disturbed area, which is also a way to recruit extra workers.
The pantropical subfamily Nasutitermitinae has a specialised caste of soldiers, known as nasutes, that have the ability to exude noxious liquids through a fontanellar gun that they use for defence. Nasutes have lost their mandibles through the course of evolution and must be fed by workers. A wide variety of monoterpene hydrocarbon have been identified in the liquids that nasutes secrete. 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).
Some species of ant 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. Ants such as Megaponera analis attack the outside of mounds and Dorylinae ants attack underground. Despite this, some termites and ants can coexist peacefully. 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. In rare cases, certain species of termites live inside active ant colonies. Some invertebrate organisms such as beetles, caterpillars, flies and millipedes are termitophiles and dwell inside termite colonies (they are unable to survive independently). As a result, certain beetles and flies have evolved with their hosts. They have developed a gland that secrete a substance that attracts the workers by licking them. Mounds may also provide shelter and warmth to birds, lizards, snakes and scorpions.
Termites are known to carry pollen and regularly visit flowers,
Many plants have developed effective defences against termites. However, seedlings are vulnerable to termite attacks and need additional protection, as their defence mechanisms only develop when they have passed the seedling stage.
To build their nests, termites use a variety of resources such as faeces which have many desirable properties as a construction material. Other building materials include partly digested plant material, used in carton nests (arboreal nests built from faecal elements and wood), and soil, used in subterranean nest and mound construction. Not all nests are visible, as many nests in tropical forests are located underground. Species in the subfamily Apicotermitinae are good examples of subterranean nest builders, as they only dwell inside tunnels. Other termites live in wood, and tunnels are constructed as they feed on the wood. Nests and mounds protect the termites' soft bodies against desiccation, light, pathogens and parasites, as well as providing a fortification against predators. Nests made out of carton are particularly weak, and so the inhabitants use counter-attack strategies against invading predators.
Arboreal carton nests of mangrove swamp-dwelling Nasutitermes are enriched in lignin and depleted in cellulose and xylans. This change is caused by bacterial decay in the gut of the termites: they use their faeces as a carton building material. Arboreal termites nests can account for as much as 2% of above ground carbon storage in mangrove swamps. These Nasutitermes nests are mainly composed of partially biodegraded wood material from the stems and branches of mangrove trees, namely, Rhizophora mangle (red mangrove), Avicennia germinans (black mangrove) and Laguncularia racemosa (white mangrove).
Some species build complex nests called polycalic nests; this habitat is called polycalism. Polycalic species of termites form multiple nests, or calies, connected by subterranean chambers. The termite genera Apicotermes and Trinervitermes are known to have polycalic species. Polycalic nests appear to be less frequent in mound-building species although polycalic arboreal nests have been observed in a few species of Nasutitermes.
Species in the genus Macrotermes arguably build the most complex structures in the insect world, constructing enormous mounds. These mounds are among the largest in the world, reaching a height of 8 to 9 metres (26 to 29 feet), and consist of chimneys, pinnacles and ridges. Another termite species, Amitermes meridionalis, can build nests 3 to 4 metres (9 to 13 feet) high and 2.5 metres (8 feet) wide. The tallest mound ever recorded was 12.8 metres (42 ft) long found in the Democratic Republic of the Congo.
The sculptured mounds sometimes have elaborate and distinctive forms, such as those of the compass termite ( Amitermes meridionalis and A. laurensis), which builds tall, wedge-shaped mounds with the long axis oriented approximately north–south, which gives them their common name. This orientation has been experimentally shown to assist thermoregulation. The north–south orientation causes the internal temperature of a mound to increase rapidly during the morning while avoiding overheating from the midday sun. The temperature then remains at a plateau for the rest of the day until the evening.
File:RayNorris termite cathedral mounds.jpg|alt=. These termite mounds have a base shaped like the base of a tree, about two meters wide and a meter high. From this base, rounded chimneys from half a meter to a meter in diameter rise to a total height of about four or five meters. The chimneys are fused together with ridges between, and terminate in rounded pinnacles at the top.|Cathedral mounds in the Northern Territory, Australia
File:Termite Magnetic DSC03613.jpg|alt=. Hundreds of compass termite mounds are visible in this photo of a field in northern Australia. The chisel-shaped mounds range from several centimeters to several meters in height.|Mounds of "compass" or "magnetic" termites ( Amitermes) oriented north–south, thereby avoiding mid-day heat
File:Termitenhuegel.jpg|alt=. This termite mound is about three meters in height and four meters across. The mound chimneys are about a meter in diameter and fuse together to form a rounded top.|Termite mound in Queensland, Australia
File:Termites in a mound.jpg|alt=. The photographer has broken off a piece of a mound to show the mound's interior. Dozens of tunnels have been exposed, and hundreds of soldiers have emerged to guard the breech in the wall.|Termites in a mound, Analamazoatra Reserve, Madagascar
File:Termitenhügel Namibia.jpg|Termite mound in Namibia
Drywood termites thrive in warm climates, and human activities can enable them to invade homes since they can be transported through contaminated goods, containers and ships. Colonies of termites have been seen thriving in warm buildings located in cold regions. Some termites are considered invasive species. Cryptotermes brevis, the most widely introduced invasive termite species in the world, has been introduced to all the islands in the West Indies and to Australia.
In addition to causing damage to buildings, termites can also damage food crops. Termites may attack trees whose resistance to damage is low but generally ignore fast-growing plants. Most attacks occur at harvest time; crops and trees are attacked during the dry season.
In Australia, at a cost of more than per year, Termites quietly reveal their secrets University of Technology Sydney. Retrieved 3 April 2023. termites cause more damage to houses than fire, floods and storms combined. Termites Victorian Building Authority. Retrieved 3 April 2023. In Malaysia, it is estimated that termites caused about RM400 million of damages to properties and buildings. The damage caused by termites costs the southwestern United States approximately $1.5 billion each year in wood structure damage, but the true cost of damage worldwide cannot be determined. Drywood termites are responsible for a large proportion of the damage caused by termites. The goal of termite control is to keep structures and susceptible ornamental plants free from termites.; Structures may be homes or business, or elements such as wooden fence posts and telephone poles. Regular and thorough inspections by a trained professional may be necessary to detect termite activity in the absence of more obvious signs like termite swarmers or alates inside or adjacent to a structure. Termite monitors made of wood or cellulose adjacent to a structure may also provide indication of termite foraging activity where it will be in conflict with humans. Termites can be controlled by application of Bordeaux mixture or other substances that contain copper such as chromated copper arsenate. In the United states, application of a soil termiticide with the active ingredient Fipronil, such as Termidor SC or Taurus SC, by a licensed professional, is a common remedy approved by the Environmental Protection Agency for economically significant subterranean termites. A growing demand for alternative, green, and "more natural" extermination methods has increased demand for mechanical and biological control methods such as orange oil.
To better control the population of termites, various methods have been developed to track termite movements. One early method involved distributing termite bait laced with immunoglobulin G (IgG) marker proteins from rabbits or chickens. Termites collected from the field could be tested for the rabbit-IgG markers using a rabbit-IgG-specific assay. More recently developed, less expensive alternatives include tracking the termites using egg white, cow milk, or soy milk proteins, which can be sprayed on termites in the field. Termites bearing these proteins can be traced using a protein-specific ELISA test. RNAi insecticides specific to termites are in development. One factor reducing investment in its research and development is concern about high potential for resistance evolution.
In 1994, termites, of the species Reticulitermes grassei, were identified in two bungalows in Saunton, Devon. Anecdotal evidence suggests the infestation could date back 70 years before the official identification. There are reports that gardeners had seen white ants and that a greenhouse had had to be replaced in the past. The Saunton infestation was the first and only colony ever recorded in the UK. In 1998, Termite Eradication Programme was set-up, with the intention of containing and eradicating the colony. The TEP was managed by the Ministry of Housing, Communities & Local Government (now the Department for Levelling Up, Housing and Communities.) The TEP used "insect growth regulators" to prevent the termites from reaching maturity and reproducing. In 2021, the UK's Termite Eradication Programme announced the eradication of the colony, the first time a country has eradicated termites.
Termites are consumed by people in many different cultures around the world. In many parts of Africa, the are an important factor in the diets of native populations.
Alates are collected when the rainy season begins. During a nuptial flight, they are typically seen around lights to which they are attracted, and so nets are set up on lamps and captured alates are later collected. The wings are removed through a technique that is similar to winnowing. The best result comes when they are lightly roasted on a hot plate or fried until crisp. cooking oil is not required as their bodies usually contain sufficient amounts of oil. Termites are typically eaten when livestock is lean and tribal crops have not yet developed or produced any food, or if food stocks from a previous growing season are limited.
In addition to Africa, termites are consumed in local or tribal areas in Asia and North and South America. In Australia, Indigenous Australians are aware that termites are edible but do not consume them even in times of scarcity; there are few explanations as to why. Termite mounds are the main sources of soil consumption (geophagy) in many countries including Kenya, Tanzania, Zambia, Zimbabwe and South Africa. Researchers have suggested that termites are suitable candidates for human consumption and Space farming, as they are high in protein and can be used to convert inedible waste to consumable products for humans.
The development of capable of constructing intricate structures without human assistance has been inspired by the complex mounds that termites build. These robots work independently and can move by themselves on a tracked grid, capable of climbing and lifting up bricks. Such robots may be useful for future projects on Mars, or for building to prevent flooding.
Termites use sophisticated means to control the temperatures of their mounds. As discussed above, the shape and orientation of the mounds of the Australian compass termite stabilises their internal temperatures during the day. As the towers heat up, the solar chimney effect (stack effect) creates an updraft of air within the mound. Wind blowing across the tops of the towers enhances the circulation of air through the mounds, which also include side vents in their construction. The solar chimney effect has been in use for centuries in the Middle East and Near East for passive cooling, as well as in Europe by the Ancient Rome. It is only relatively recently, however, that climate responsive construction techniques have become incorporated into modern architecture. Especially in Africa, the stack effect has become a popular means to achieve natural ventilation and passive cooling in modern buildings.
Few zoos hold termites, due to the difficulty in keeping them captive and to the reluctance of authorities to permit potential pests. One of the few that do, the Zoo Basel in Switzerland, has two thriving Macrotermes bellicosus populations – resulting in an event very rare in captivity: the mass migrations of young flying termites. This happened in September 2008, when thousands of male termites left their mound each night, died, and covered the floors and water pits of the house holding their exhibit.
African tribes in several countries have termites as , and for this reason tribe members are forbidden to eat the reproductive alates. Termites are widely used in traditional popular medicine; they are used as treatments for diseases and other conditions such as asthma, bronchitis, hoarseness, influenza, sinusitis, tonsillitis and whooping cough. In Nigeria, Macrotermes nigeriensis is used for spiritual protection and to treat wounds and sick pregnant women. In Southeast Asia, termites are used in ritual practices. In Malaysia, Singapore and Thailand, termite mounds are commonly worshiped among the populace. Abandoned mounds are viewed as structures created by spirits, believing a local guardian dwells within the mound; this is known as Keramat and Datok Kong. In urban areas, local residents construct red-painted shrines over mounds that have been abandoned, where they pray for good health, protection and luck.
+ Diversity of Isoptera by continent: ! scope="col" Asia
! scope="col" Africa
! scope="col" North America
! scope="col" South America
! scope="col" Europe
! scope="col" Australia
Description
Caste system
Life cycle
Reproduction
Behaviour and ecology
Diet
Predators
Parasites, pathogens, and viruses
Locomotion and foraging
Competition
Communication
Defence
Relationship with other organisms
Relationship with the environment
Nests
Mounds
Shelter tubes
Relationship with humans
As pests
As food
In agriculture
In science and technology
In culture
See also
Notes
Cited literature
pest control Sydney
External links
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