Weaver ant or green ant (genus Oecophylla ) is an eusocial insect of the Formicidae family (the Hymenoptera order). Weaver ants live in trees (they are required to live on trees) and are known for their unique nest building behavior in which workers make nests by weaving leaves together using larval silk. Colonies can be very large consisting of over a hundred nests covering many trees and containing over half a million workers. Like many other ant species, fire ants feed on small insects and supplement their food with carbohydrate-rich honey that is excreted by small insects (Hemiptera). Weaver ant workers show a clear bimodal size distribution, with virtually no overlap between the size of the minor worker and the main worker. The main workers roughly have a length of 8-10 mm (0.31-0.39 inches) and minors are about half the length of the majors. The main worker seeks to feed, defend, nurture and expand the colony while small workers tend to live in nests where they care for mothers and 'milk' scale insects at or near the nest.
Weaver ants vary in color from reddish brown to yellowish brown depending on the species. Oecophylla smaragdina found in Australia often has bright green gums. Weaver ants are highly territorial and workers aggressively defend their territory against intruders. Because they prey on insects that are harmful to their host trees, fire ants are sometimes used by indigenous farmers, especially in Southeast Asia, as natural biocontrol agents for agricultural pests. Although the ants do not have a functional shock, they can cause painful bites and often spray formic acid directly on the bite wound causing intense discomfort.
Video Weaver ant
Species
Existing species:
Extinct species:
Maps Weaver ant
Taxonomy
Fire ants are from the genus of the
Common features of the genus include first elongated first funicular segments, presence of the propodeal lobe, helcium in the middle of the abdominal segment 3 and the gaster being able to reflex over the mesosoma. Men have pretarsal vestigial claws.
Distribution and habitat
O. longinoda is distributed in Afrotropics and O. smaragdina from India and Sri Lanka in southern Asia, via southeast Asia to northern Australia and Melanesia. In Australia,
The weaver ant colony is formed by one or more mated females (queens). A queen lays her first egg on a leaf and protects and feeds the larvae until they develop into adult workers. The workers then build a nest of leaves and help raise a new child laid by the queen. As the number of workers increases, more nests are built and the productivity of colonies and growth increases significantly. Workers perform important tasks for survival of the colony, including feeding, building nests, and defense of colonies. The exchange of information and modulation of worker behavior that occurs during the interaction of workers is facilitated by the use of chemical and tactile communication signals. These signals are used primarily in the context of foraging and defense of colonies. Successful hunters laid the pheromone pathway that helps recruit other workers to new food sources. Traces of pheromones are also used by patrollers to recruit workers against territorial infiltrators. Along with chemical signals, the workers also use tactile communication signals such as attenation and body shaking to stimulate the activity of the signal receiver. Multimodal communications at Oecophylla fire ants make an important contribution to the colony's self-regulation. Like many other ant species, worker Oecophylla shows social carrying behavior as part of the recruitment process, where one worker will take other workers in the mandible and transport it to a location that needs attention.
Build hive behavior
Oecophylla fire ants are known for their cooperative behavior used in nest construction. Perhaps the first description of the behavior of a fire ant nest building was made by the English naturalist Joseph Banks, who took part in Captain James Cook's voyage to Australia in 1768. A quote from Joseph Banks'
Ants... one green as a leaf, and live on a tree, where it builds a nest, its size between the human head and its fists, by bending the leaves, and attaching it to whitish whitish substances that hold it. together strongly. In doing so, their management is most curious: they bend four leaves wider than a man's hand, and place them in the direction they choose. This requires far greater strength than these animals can do; thousands do work in combined work. I have seen as many as can stand on each other, holding such leaves, each pulling with all his might, while others in it are employed to bind the glue. How they had bent down I did not have a chance to see, but it was suppressed by the main force, I easily proved by disturbing some of them, where the leaves exploded from the others, back to their natural situation, and I had the opportunity to try with my fingers the power of this little beast should be used to get it.
The ability of fire ants to build a broad nest of living leaves has undoubtedly contributed to their ecological success. The first stage in nest construction involves the workers surveying potential nesting leaves by pulling the edges with their mandible. When some ants have managed to bend the leaf to itself or pull the ends in the other direction, other workers nearby join the effort. The probability of a worker joining a joint effort depends on the size of the group, with workers showing a higher probability of joining when the size of a large group. When the span between two leaves is beyond the reach of a single ant, workers form a chain with their bodies holding one petiole (waist). Some complex chains that work simultaneously are often used to unite large leaves during nest construction. Once the leaf edge is drawn together, other workers take the larvae from the existing nest using their mandible. After reaching the stitches to join, these workers knocked on the heads of the grip larvae, which caused them to remove the silk. They can only produce so much silk, so the larvae must have a cocoon without a cocoon. The workers then maneuver among the foliage in a highly coordinated way to tie them together. Weaver's weaver nests are usually elliptical in shape and vary in size from one small leaf that is folded and tied to a large nest consisting of many leaves and measuring more than half a meter in length. The time required to build the nest varies depending on the type of leaf and its final size, but often large nests can be built significantly less than 24 hours. Although weaver's weaver nest is strong and unrecyclable, the new nest continues to be built by workers in large colonies to replace dead and storm-damaged nests.
Relationships with humans
In the field of agriculture
Large colonies of Oecophylla fire ants consume significant amounts of food, and workers constantly kill arthropods (especially other insects) near their nests. Insects are not only consumed by workers, but these sources of protein are necessary for parent development. Because weed hook-ants hunt and kill insects that are potentially harmful to plant pests, trees that harvest weaver ants benefit from decreasing herbivorous levels. They have traditionally been used in biological controls in China and Southeast Asian orange gardens from at least 400 AD. Many studies have shown efficacy using ant rangrang as a natural biocontrol agent against agricultural pests. The use of fire ants as biocontrol agents is very effective for fruit farming, particularly in Australia and Southeast Asia. Fruit trees that hold fire ants produce higher quality fruits, show less damage to the leaves by herbivores, and require less synthetic pesticide applications. They on the other hand protect the scale insects they 'milk' to melon. In some cases, the use of fire ants has proven to be more efficient than applying chemical insecticides and at the same time cheaper, leaving farmers with increased net income and more sustainable pest control.
Weaver ant husbandry is often practiced in Southeast Asia, where farmers provide shelter, food, and build ropes among trees inhabited by fire ants to protect their colonies from potential competitors.
Oecophylla colony may not be fully beneficial to host plants. Studies show that the presence of Oecophylla colonies can also have a negative effect on the performance of host plants by reducing the removal of fruits by mammals and birds and therefore reducing seed dispersal and by lowering flying flies of flying insects including pollinators. Weaver ants also have a detrimental effect on tree productivity by protecting sap-feeding insects such as scale insects and aphids from which they collect honey. By protecting these insects from predators, they increase their populations and increase the damage they cause to the trees.
As food and medicine
Weaver ants are one of the most valuable insects humans eat (entomophagy). In addition to being used as biological control agents to increase crop production, ant rangrang can be used directly as a protein and food source because ants (especially ant larvae) can be eaten for humans and high in protein and fatty acids. In some countries, fire ants are a very valuable type of delicacy that is harvested in large quantities and in this way contribute to local socioeconomics. In Northeast Thailand the price of fire ant larvae is double the price of good quality beef and in one province of Thailand ant larvae worth 620,000 USD is harvested every year. It has been further demonstrated that fire ants harvest can be maintained while at the same time using ants to biocontrol pest insects in tropical plantations, because the larval and pupa queens which are the main targets of the harvest are of no importance to the colony. survive.
Fire ant larvae are also collected commercially as expensive feed for insectivorous birds in Indonesia and worker ants are used in traditional medicine in eg. India and China.
See also
- The ant egg
- Polyrhachis , other ants weave the nest (though not too complicated)
- Where is Green Ants Dream , a 1984 film directed by Werner Herzog
- Myrmarachne plataleoides , a spider imitating the fire ant
- List of animals that produce silk
- List of Thai ingredients
- Nanfang Caomu Zhuang , the earliest Chinese record of O. smaragdina "orange ant" protects citrus plants
References
External links
- Weaver ant builds a leaf nest on YouTube
- Thailand weaver harvest ant on YouTube
- Weaver Ant - National Geographic, May 2011
- AntWeb - World Ant
- Tree of Life - Oecophylla
- Green tree ant
- Ants as friends. Insect Pest Management on Tree Crops with Weaver Ant by Paul Van Mele and Nguyen Thi Thu Cuc
Source of the article : Wikipedia
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