Nasutitermes corniger | |
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Arthropoda |
Class: | Insecta |
Order: | Blattodea |
Infraorder: | Isoptera |
Family: | Termitidae |
Genus: | Nasutitermes |
Species: | N. corniger |
Binomial name | |
Nasutitermes corniger (Motschulsky, 1855) | |
Nasutitermes corniger is a species of arboreal termite that is endemic to the neotropics. It is very closely related to Nasutitermes ephratae . [1] The species has been studied relatively intensively, particularly on Barro Colorado Island, Panama. These studies and others have shown that the termite interacts with many different organisms including a bat that roosts in its nest and various species of ants that cohabit with the termite.
The nests of N. corniger are dark brown on the surface and have small bumps over their exterior. When small (less than 20 cm in diameter) they tend to be spherical but as they grow they become more elliptical. There may also be localised lobes on the surface of the nest. The queen lives in a chamber located in the centre of the nest, (often near the tree trunk or branch to which the nest is attached), that is up to 8 cm wide and 1 cm high and heavily reinforced. The thickness of the walls in the nest decreases away from the queen and towards the exterior although if the nest is attacked by predators then the walls will be reinforced. In one study of their nests the heaviest nest identified weighed 28 kilograms and measured 68 cm by 46 cm by 34 cm. [1]
Fertile individuals of N. corniger have black wings, dark bodies, and ocelli which are located relatively far from the eyes. [1]
Termite colonies are examples of eusocial insects. Eusocial insects are animals that develop large, multigenerational cooperative societies that assist each other in the rearing of young, often at the cost of an individual's life or reproductive ability. Such altruism is explained in that eusocial insects benefit from giving up reproductive ability of many individuals to improve the overall fitness of closely related offspring. Hamilton's rule is the key to explaining this phenomenon, where altruism is justified evolutionarily when the benefit to the individual receiving the help, weighted by the relatedness to said individual, outweighs the cost to the organism being altruistic. In most cases, termites included, individuals specialize to fill different needs that the overall colony may have. These are called castes. In Nasutitermes as well as most other termite species, there are three main castes: reproductive alates, workers, and soldiers.
The benefits to being altruistic come in two ecological modes: “life insurers” and “fortress defenders”. [2] Most Hymenoptera, the large majority of social insects, are life insurers, where eusociality is adapted as a safeguard from decreased life expectancy of offspring. [3] Termites, as fortress defenders, benefit from working together to best exploit a valuable ecological resource, in the case of Nasutitermes corniger a vast wood gallery. Fortress defense is sufficient to evolve eusociality when three criteria are met: food coinciding with shelter, selection for defense against intruders and predators, and the ability to defend such a habitat. [4] Termite colonies are generally large enclosed nests or mounds that house large supplies of wood for the termites to exploit, fulfilling the first criteria for fortress defense. In N. corniger, the soldier caste has had their heads modified to spew a noxious, sticky liquid when under attack from Tamandua anteaters. [5] The secretion contains pinene, limonene and other high molecular weight compounds that deter the anteater from returning. The termites then remain on guard near the breach for several minutes. This adaptive morphology and defense of the habitat are sufficient for satisfying the second two criteria for fortress defense. The fortress defense strategy necessitated the evolution of soldiers first, which has resulted in the unique specialization of the nasute termites.
Nasutitermes corniger exhibits a large amount of aggression to rival conspecific colonies. This implies that there is a method of kin recognition among N. corniger that allow it to distinguish between its colony and the next. While specific studies have not been done in N. corniger, similar species in Microcerotermes and many other termites show that they are able to detect scent on each other. It has been shown that some separate colonies display relatively low aggression to each other and oftentimes result in colony fusion. It is of note that these colonies will show massive aggression towards other colonies, indicating it is not a loss in aggressive behavior but a failure in recognition. It has been shown that colonies that exhibit this nonaggressive behavior have a relatively low average within-colony relatedness of .35, whereas colonies that retained mutually aggressive behavior had a higher relatedness average of .55. The nonaggressive colonies often had polygamous reproductive individuals, and may have a broader template of acceptable odor clues, leading to recognition of other colonies. [6]
The number of fertile individuals produced by colonies of N. corniger varies widely. Mature colonies with between 50,000 and 400,000 infertile workers generally produce between 5,000 and 25,000 alates. In some years, large colonies do not produce a fertile brood. Alate nymphs develop through five instars and spend between 5 and 8 months within the colony before leaving to mate. When the alates are mature they typically account for 35% of the colony's biomass. More males than females are produced from each colony but because females are heavier (by between 20 and 40%) the energy investment in each sex is similar. [7] Newly formed colonies tend to have multiple queens and kings all living in the same royal chamber. Slightly older colonies tend to consist of multiple queens (up to 33) but only one king, in these cases the species can be considered polygynous. Over several years the species turns to being monogamous, having only one queen and one king. Being polygynous in the early stages of the colony is advantageous as it allows the colony to produce many workers in a short period of time and allows the production of female alates more quickly than if they were monogamous from the start. [8]
N. corniger have been found in Mexico, Guatemala, Honduras, Costa Rica, Panama, Venezuela, Trinidad, Tobago, Bolivia, Puerto Rico [1] and more recently in Florida. [9]
Numerous species of ants cohabit the nests of N. corniger or colonise them once the termites have abandoned them. Some species prey on the termites but others do not. Studies with radioactive tracers have shown that when cohabiting nutrients flow both ways between the ants and the termites. Monacis bispinosa , also known as Dolichoderus bispinosus is one of the most common ant species to cohabit with the termites but is susceptible to their chemical defences and cannot prey on live termites. Camponotus abdominalis associates with termites less often but is an aggressive predator of the termites. Camponotus species and Dolichoderus diversus have been found to inhabit N. corniger nests that have been abandoned. [10]
Crematogaster brevispinosa rochai is one subspecies of ant whose interaction with N. corniger has been studied. C. b. rochai lives in areas of caatinga in Brazil. No queens of the ant have been found in the nests but their larvae of all castes and sexes have been. Nests that contain C. b. rochai do not have a termite queen in either. It can therefore be concluded that both the ants and termites are members of polydomous colonies that each have numerous nest sites. The ants and termites are segregated within the nest and do not normally come into contact with each other. C. b. rochai plug channels at the boundary of the areas they occupy to cause this segregation. On occasions when the ants and termites do come into contact with each other (e.g. if the nest is broken into) they are rarely aggressive and tend to avoid each other instead. It has been hypothesised that the hydrocarbon content of their cuticles may have changed to allow them to live together relatively peacefully. [10]
The termites are thought to benefit from the association as the ants leave debris in the nest containing nitrogen and that this increases the availability of this important nutrient in an environment where it is scarce. They may also benefit from the ants protecting the nest from predators. The ants benefit as the termite nests provide an ideal location to raise broods, particularly of reproductive castes. The climate is suitable for this and the nests are easily defended against predators. Other Nasutitermes species have been found to produce anti-fungal compounds and these would also be beneficial to the ants although it is not known if N. corniger do produce such compounds. [10]
The White-throated Round-eared Bat, Lophostoma silvicola , roosts inside the nests of N.corniger. Males excavate the roost themselves, expending considerable energy whilst doing so. They consequently gain reproductive success as a harem of females will join them in the roost. The termite nest is an ideal temperature for raising young and provides protection from predators of the bats. N. corniger repair the damage made to the nest by the bat meaning that the males have to constantly maintain the roost. Once the bats leave the cavity is filled by the termites within a few weeks. [11] Scientists are currently investigating how the bats are able to create the roosts without being attacked by the termites. [12]
Several bird species including trogons, puffbirds and parakeets also form nests in termite nests. [13] These can be distinguished from those made by bats as they have a horizontal entrance whereas those made by bats have a vertical entrance at the base of the nest. [14]
The entire gut flora of a termite very closely related to N. corniger has been analysed using metagenomics to determine the function of different microbes in their gut. [15] Typical to all wood-feeding higher termites, bacterial gut microbiota in the guts of N. corniger are dominated by insect-specific members of TG3 (candidate_phylum), Fibrobacterota, and Spirochaetota. [16] It has also been shown that the same bacterial lineages are preferentially enriched in the cellulolytic bacterial community that is associated with wood particles in the gut. [17] In addition to a role in fiber digestion, Symbiotic bacteria in N. corniger have also been shown to fix nitrogen at a rate of 0.25-1.0 mg N per colony per hour. This suggests a nitrogen doubling time of 200–500 days making it possible for the whole population of the colony to be replaced once or twice each year. [18]
Termites are a group of detritophagous eusocial insects which consume a wide variety of decaying plant material, generally in the form of wood, leaf litter, and soil humus. They are distinguished by their moniliform antennae and the soft-bodied and often unpigmented worker caste for which they have been commonly termed "white ants"; however, they are not ants, to which they are only distantly related. About 2,972 extant species are currently described, 2,105 of which are members of the family Termitidae.
Autothysis or suicidal altruism is the process where an animal destroys itself via an internal rupturing or explosion of an organ which ruptures the skin. The term was proposed by Ulrich Maschwitz and Eleonore Maschwitz in 1974 to describe the defensive mechanism of Colobopsis saundersi, a species of ant. It is caused by a contraction of muscles around a large gland that leads to the breaking of the gland wall. Some termites release a sticky secretion by rupturing a gland near the skin of their neck, producing a tar effect in defense against ants.
Blattodea is an order of insects that contains cockroaches and termites. Formerly, termites were considered a separate order, Isoptera, but genetic and molecular evidence suggests they evolved from within the cockroach lineage, cladistically making them cockroaches as well. The Blattodea and the mantis are now all considered part of the superorder Dictyoptera. Blattodea includes approximately 4,400 species of cockroach in almost 500 genera, and about 3,000 species of termite in around 300 genera.
Reticulitermes flavipes, the eastern subterranean termite, is the most common termite found in North America. These termites are the most economically important wood destroying insects in the United States and are classified as pests. They feed on cellulose material such as the structural wood in buildings, wooden fixtures, paper, books, and cotton. A mature colony can range from 20,000 workers to as high as 5 million workers and the primary queen of the colony lays 5,000 to 10,000 eggs per year to add to this total.
The white-throated round-eared bat is a bat species found from Honduras to Bolivia, Paraguay and Brazil. It creates roosts inside the nests of the termite, Nasutitermes corniger. It thrives on a mainly insect-based diet, focusing on the surfaces of foliage to hunt, and also eats fruit and pollen. It has a very wide range and is a common species over much of that range, so the International Union for Conservation of Nature has assessed its conservation status as being of "least concern".
The gyne is the primary reproductive female caste of social insects. Gynes are those destined to become queens, whereas female workers are typically barren and cannot become queens. Having a queen is what makes a "queenright" hive, nest, or colony of eusocial insects. A colony with multiple queens is said to be a polygyne form, whereas one with only one is a monogyne form.
The Macrotermitinae, the fungus-growing termites, constitute a subfamily of the family Termitidae that is only found within the Old World tropics.
Eusociality is the highest level of organization of sociality. It is defined by the following characteristics: cooperative brood care, overlapping generations within a colony of adults, and a division of labor into reproductive and non-reproductive groups. The division of labor creates specialized behavioral groups within an animal society which are sometimes referred to as 'castes'. Eusociality is distinguished from all other social systems because individuals of at least one caste usually lose the ability to perform behaviors characteristic of individuals in another caste. Eusocial colonies can be viewed as superorganisms.
Zootermopsis angusticollis is a species of termite (Isoptera) in the family Archotermopsidae, a group known as the Pacific dampwood termites, or the rottenwood termites. As their name suggests, the dampwood termites can only survive by living off of wood that contains high amounts of moisture. They are found along the wet environments of the Pacific coast of North America. Most are found in the states of California, Oregon, Washington, Idaho, Western Nevada and in southern British Columbia. Termites are well known to be destroyers of wood, and although the dampwood termites can cause some damage, they are not as notoriously known to cause as much damage to buildings as the drywood termites. They occasionally have been carried to other parts of the country through wood shipments, but have not been able to become established in these areas due to undesirable environmental conditions.
Within the insect order Hymenoptera, the Halictinae are the largest, most diverse, and most recently diverged of the four halictid subfamilies. They comprise over 2400 bee species belonging to the five taxonomic tribes Augochlorini, Thrinchostomini, Caenohalictini, Sphecodini, and Halictini, which some entomologists alternatively organize into the two tribes Augochlorini and Halictini.
Reticulitermes is a termite genus in the family Rhinotermitidae. They are found in most temperate regions on Earth including much of Asia and the Middle East, Western Europe, and all of North America.
Macrotermes bellicosus is a species of Macrotermes. The queens are the largest amongst known termites, measuring about 4.2 inches (110 mm) long when physogastric. The workers average 0.14 in (3.6 mm) in length and soldiers are slightly larger. Bellicosus means "combative" in Latin. The species is a member of a genus indigenous to Africa and South-East Asia.
Incisitermes minor is a species of termite in the family Kalotermitidae known commonly as the western drywood termite. It is native to western North America, including the western United States and northern Mexico. It has been found in many other parts of the United States, all the way to the East Coast. It has been reported from Toronto. It has been introduced to Hawaii. It has been noted in China and it is not uncommon in Japan. This is an economically important pest of wooden structures, including houses. In California and Arizona alone its economic impact is estimated to be about $250 million per year.
Cryptotermes brevis is a species of termite in the family Kalotermitidae, commonly known as the West Indian drywood termite or the powderpost termite. It is able to live completely inside timber structures or articles made of wood such as furniture without any outside source of water. It is frequently introduced into new locations inadvertently, and causes damage to the structural timbers of buildings and to wooden objects such as furniture.
An ergatoid is a permanently wingless reproductive adult ant or termite. The similar but somewhat ambiguous term ergatogyne refers to any intermediate form between workers and standard gynes. Ergatoid queens are distinct from other ergatogyne individuals in that they are morphologically consistent within a species and are always capable of mating, whereas inter caste individuals, another class of ergatogynes, often are not. Ergatoids can exhibit wide morphological differences between species, sometimes appearing almost identical to normal workers and other times being quite distinct from both workers and standard queens. In addition to morphological features, ergatoids among different species can exhibit a wide range of behaviors, with some ergatoids acting only as reproductives and others actively foraging. Ergatoid queens have developed among a large number of ant species, and their presence within colonies can often provide clues on the social structures of colonies and as to how new colonies are founded. Without wings, almost all species of ants that solely produce ergatoid queens establish new colonies by fission.
Reticulitermes virginicus is a species of subterranean termite native to North America, found often in the southern United States. It was described in 1907.
Amitermes floridensis, commonly known as the Florida darkwinged subterranean termite, is a species of eusocial insect in the family Termitidae. It feeds on rotting wood, reached by a network of tunnels. It is endemic to west central Florida and was first described in 1989.
Odontotermes obesus is a species of termite in the family Termitidae. It is native to tropical southwestern Asia. This termite cultivates a symbiotic fungus in a special chamber in the nest. Workers gather vegetable detritus which they bring back to the colony, chewing up the material to make a suitable substrate on which the fungus will grow.
Constrictotermes cyphergaster is a Neotropical species of open-air foraging nasute termite within the genus Constrictotermes. This species is distributed widely throughout South America and lives within xeric habitats such as the savannas found in Paraguay, Bolivia, Central Brazil, and Northern Argentina. C. cyphergaster primarily builds arboreal and transient epigeic nests and mainly consumes dead woods at varying stages of decomposition.