Duroia hirsuta | |
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Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Angiosperms |
Clade: | Eudicots |
Clade: | Asterids |
Order: | Gentianales |
Family: | Rubiaceae |
Genus: | Duroia |
Species: | D. hirsuta |
Binomial name | |
Duroia hirsuta | |
Duroia hirsuta is a myrmecophyte tree species from the Amazon Forest. It is one of some 37 species of Duroia, which are shrubs or canopy trees in the family Rubiaceae, favouring ants (myrmecophilous), and occurring in Central America as far north as Mexico, the Amazon Basin, the Guiana Shield, the Brazilian Atlantic coast and planalto.
A number of Duroia species, and possibly all, are capable of biochemical interactions inhibiting the growth of neighbouring plants. Analysis of root extracts from Duroia hirsuta have yielded a strong plant growth inhibitor plumericin, a tetracyclic iridoid lactone, and duroin, another iridoid lactone. [1] [2]
This process, common amongst plants, is termed allelopathy. In the case of Duroia hirsuta, the chemical inhibitor is aided by the Lemon Ant, a resident on and in the tree, and playing an active role in suppressing and destroying plant growth in the vicinity of their host by injecting and spraying formic acid, and defending against herbivores - other ant species such as Azteca spp. and Allomerus octoarticulatus demerarae exhibit the same mutualism. [3] The area around this understory tree is often devoid of all other plant types, leading to the local name "Devil's garden." [4] The cost to the host plant for this protection is considerable, since the resident ants subject the tree to increased leaf cutting. [5] Trees that grow outside the cleared area often have the living tissues of their trunks excavated and galled for ant accommodation. [6]
The ants involved in the relationship specifically aid the plant in defense against herbivores, supplying of nutrients, and pollination. [7] [8] Their mutualism is strengthened by the positive size-dependent growth each gains from the relationship. [9] One specific type of ant, the M. Schummanni are notorious for supporting the largest plant sizes and growth rates. [10]
The environmental conditions that influence the fitness of the species also has an impact on the amount of rewards reaped by the ants involved in the mutualistic relationship with the plant. The effectiveness of ants is greater in conditions where nutrients are scarce as opposed to environments with favorable conditions for the plant. [7] Size of the plant is a great indicator of fitness and is often measured by the amount of Domatia present. [9] Ants can aid the plant in receiving more sunlight by clearing the canopies above the plant and limit competition from other nearby plants. [10]
Mutualism describes the ecological interaction between two or more species where each species has a net benefit. Mutualism is a common type of ecological interaction, one that can come from a parasitic interaction. Prominent examples include most vascular plants engaged in mutualistic interactions with mycorrhizae, flowering plants being pollinated by animals, vascular plants being dispersed by animals, and corals with zooxanthellae, among many others. Mutualism can be contrasted with interspecific competition, in which each species experiences reduced fitness, and exploitation, or parasitism, in which one species benefits at the expense of the other.
Allelopathy is a biological phenomenon by which an organism produces one or more biochemicals that influence the germination, growth, survival, and reproduction of other organisms. These biochemicals are known as allelochemicals and can have beneficial or detrimental effects on the target organisms and the community. Allelopathy is often used narrowly to describe chemically-mediated competition between plants; however, it is sometimes defined more broadly as chemically-mediated competition between any type of organisms. Allelochemicals are a subset of secondary metabolites, which are not directly required for metabolism of the allelopathic organism.
Myrmecophytes are plants that live in a mutualistic association with a colony of ants. There are over 100 different genera of myrmecophytes. These plants possess structural adaptations that provide ants with food and/or shelter. These specialized structures include domatia, food bodies, and extrafloral nectaries. In exchange for food and shelter, ants aid the myrmecophyte in pollination, seed dispersal, gathering of essential nutrients, and/or defense. Specifically, domatia adapted to ants may be called myrmecodomatia.
In myrmecology and forest ecology, a devil's garden is a large stand of trees in the Amazon rainforest consisting of at most three tree species and the ant Myrmelachista schumanni. Devil's gardens can reach up to sizes of 600 trees and are inhabited by a single ant colony, containing up to 3 million workers and 15,000 queens. In a 2002 to 2004 census of the Amazon, devil's gardens were shown to have grown by 0.7 % per year. The relationship between tree and ant may persist for more than 800 years. A devil's garden is considered an example of mutualism, a type of symbiotic relationship between species.
Myrmelachista schumanni, also known as the lemon ant, is a species of ant from South America. It is notable for the creation of devil's gardens. Using its own herbicide, they kill off all the plants in an area except for the myrmecophytes, or ant-plants, in which they reside.
Myrmecochory ( ; from Ancient Greek: μύρμηξ, romanized: mýrmēks and χορεία khoreíā is seed dispersal by ants, an ecologically significant ant–plant interaction with worldwide distribution. Most myrmecochorous plants produce seeds with elaiosomes, a term encompassing various external appendages or "food bodies" rich in lipids, amino acids, or other nutrients that are attractive to ants. The seed with its attached elaiosome is collectively known as a diaspore. Seed dispersal by ants is typically accomplished when foraging workers carry diaspores back to the ant colony, after which the elaiosome is removed or fed directly to ant larvae. Once the elaiosome is consumed, the seed is usually discarded in underground middens or ejected from the nest. Although diaspores are seldom distributed far from the parent plant, myrmecochores also benefit from this predominantly mutualistic interaction through dispersal to favourable locations for germination, as well as escape from seed predation.
Vachellia cornigera, commonly known as bullhorn acacia, is a swollen-thorn tree and Myrmecophyte native to Mexico and Central America. The common name of "bullhorn" refers to the enlarged, hollowed-out, swollen thorns that occur in pairs at the base of leaves, and resemble the horns of a steer. In Yucatán it is called "subín", in Panamá the locals call them "cachito". The trees are commonly found in wet lowlands
Plant defense against herbivory or host-plant resistance (HPR) is a range of adaptations evolved by plants which improve their survival and reproduction by reducing the impact of herbivores. Plants can sense being touched, and they can use several strategies to defend against damage caused by herbivores. Many plants produce secondary metabolites, known as allelochemicals, that influence the behavior, growth, or survival of herbivores. These chemical defenses can act as repellents or toxins to herbivores or reduce plant digestibility. Another defensive strategy of plants is changing their attractiveness. To prevent overconsumption by large herbivores, plants alter their appearance by changing their size or quality, reducing the rate at which they are consumed.
Deborah M. Gordon is an American biologist best known for her impactful research in the behavioral ecology of ants and her studies on the operations of ant colonies without a central control. In addition to overseeing The Gordon Lab, she is currently a Professor of Biology at Stanford University.
Pseudomyrmex spinicola is a species of red myrmecophyte-inhabiting neotropical ants which are found only in Nicaragua and Costa Rica. They live in the thorns of tropical trees like Acacia collinsii or Acacia allenii, feeding on nectaries along with the protein and lipid-rich beltian bodies. These bodies are named for Thomas Belt, a naturalist who first described the interactions between acacias and ants in his 1874 book Naturalist in Nicaragua. Belt's book in fact described ants of this species, then unknown.
Inga edulis, known as ice-cream bean, ice-cream-bean, joaquiniquil, cuaniquilguama or guaba, is a fruit native to South America. It is in the mimosoid tribe of the legume family Fabaceae. It is widely grown, especially by Indigenous Amazonians, for shade, food, timber, medicine, and production of the alcoholic beverage cachiri. It is popular in Peru, Ecuador, Pernambuco-Brazil, Venezuela, Guyana and Colombia. The taxonomic name Inga is derived from its name with the Tupí people of South America (ingá) while the species name edulis is Latin for "edible". The common name "ice-cream bean" alludes to the sweet flavor and smooth texture of the pulp.
Vachellia drepanolobium, more commonly known as Acacia drepanolobium or whistling thorn, is a swollen-thorn acacia native to East Africa. The whistling thorn grows up to 6 meters tall. It produces a pair of straight spines at each node, some of which have large bulbous bases. These swollen spines are naturally hollow and occupied by any one of several symbiotic ant species. The common name of the plant is derived from the observation that when wind blows over bulbous spines in which ants have made entry and exit holes, they produce a whistling noise.
A Beltian body is a detachable tip found on the pinnules of some species of Acacia and closely related genera. Beltian bodies, named after Thomas Belt, are rich in lipids, sugars and proteins and often red in colour. They are believed to have evolved in a symbiotic relationship with ants. The ants live inside special plant structures (domatia) or near the plant and keep away herbivores.
Tetraponera is a genus of ants in the subfamily Pseudomyrmecinae that are commonly known as slender ants and are characterized by their arboreal nature and slender bodies. The 96 described species of Tetraponera all of which live in hollow structures of plants and trees, such as thorns or branches; these hosts are known as myrmecophytes. Tetraponera species are closely related to the New World genus of ants Pseudomyrmex, but differ in their relationships with host plants.
Plant use of endophytic fungi in defense occurs when endophytic fungi, which live symbiotically with the majority of plants by entering their cells, are utilized as an indirect defense against herbivores. In exchange for carbohydrate energy resources, the fungus provides benefits to the plant which can include increased water or nutrient uptake and protection from phytophagous insects, birds or mammals. Once associated, the fungi alter nutrient content of the plant and enhance or begin production of secondary metabolites. The change in chemical composition acts to deter herbivory by insects, grazing by ungulates and/or oviposition by adult insects. Endophyte-mediated defense can also be effective against pathogens and non-herbivory damage.
Duroia is a genus of flowering plants in the family Rubiaceae. The genus is found from Costa Rica to tropical South America.
Pearl bodies are small, lustrous, pearl-like food bodies produced from the epidermis of leaves, petioles and shoots of certain plants. They are rich in lipids, proteins and carbohydrates, and are sought after by various arthropods and ants, that carry out vigorous protection of the plant against herbivores, thus functioning as a biotic defence. They are globose or club-shaped on short peduncles, easily detached from the plant, and are food sources in the same sense as Beltian bodies, Müllerian bodies, Beccarian bodies, coccid secretions and nectaries. They occur in at least 19 plant families (1982) with tropical and subtropical distribution.
Leonardoxa africana is a tropical tree endemic to west-central Africa and southeastern Nigeria. It is divided into four sub-species, of which three are myrmecophytes.
Megan Frederickson is a Canadian evolutionary biologist who is a professor of Ecology and Evolutionary Biology at the University of Toronto. Her research considers the evolution of cooperation and the ecological genetics of mutualism.
Myrmecodia tuberosa, the ant plant, is an epiphytic plant. The species has a symbiotic relationship with some ant species where ants use the hollow body of the plant as shelter, defend the plant from other insects, and provide nutrients to the plant through their waste.