Meat ant
Encyclopedia
Meat ants also known as meat-eater ants or gravel ants, are a species
of ant
belonging to the Iridomyrmex
genus. They can be found throughout Australia
.
Meat ants live in underground nests of over 64,000 ants. Many nests may be connected together into a supercolony that stretches up to 650 metres (0.4 miles). Nest holes are regularly arranged, and each leads to a separate series of branched tunnels, which typically do not connect with the tunnels from other holes. Satellite colonies are commonly formed by reproductively active daughter queens near the main nest, usually around five to ten metres away, sometimes as much as 50 metres.
The use of different parts of the nests is largely dependent on environmental factors, for example excessive shading of the main mound will stimulate the occupation of different parts of the nest or the expansion of satellite colonies.
Meat ants cover their nest mounds with gravel
, sand
, leaf petiole
s, twigs, seed capsules, mollusk shells and other small items, which heat the nest quicker in the morning.
Meat ants are omnivorous
scavengers that get their name from their use, by farmers, to clean carcasses. Meat ants are diurnal. On hot days foraging is bimodal, with all activity ceasing during the heat of the day.
Like other Iridomyrmex species, they engage in a mutualistic relationship with certain caterpillar
s and butterflies
of specific species which produce secretions that meat ants will feed on. In return, they protect the caterpillars from predation
. Honeydew collected from hemipterous insects
is the main component of the diet of most meat ant colonies. This is supplemented by scavenging for dead invertebrate
s.
, meaning that they take on different roles in the colony at different ages. Young ants care for eggs and larvae in the nest. Older ants form part of large foraging parties to exploit significant stationary food resources, such as a dead animal or a colony of hemipterous insects. Older ants undertake lone foraging across open ground, predominately collecting invertebrates and 'building material.' The oldest ants are involved in inter-colony competition.
Meat ants exhibit aggressive competitive interaction with other species of ants and are therefore a dominant component of Australian ant communities. Other species employ strategies that exploit resources or habitats not favoured by meat ants, or forage at alternate times (like the common crepuscular Camponotus species). They are aggressive towards meat ants from neighbouring colonies. Old workers engage in ritual combat along borders between colonies to establish foraging boundaries. Like many other species of ant, meat ants are able to communicate with one another using chemical cues.
s, an introduced pest
, as the toxins that usually kill a cane toad's predator do not affect the meat ants. The cane toad's normal response to attack is to stand still and let their toxin kill the attacker, which allows the ant to attack and eat the toad.
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
of ant
Ant
Ants are social insects of the family Formicidae and, along with the related wasps and bees, belong to the order Hymenoptera. Ants evolved from wasp-like ancestors in the mid-Cretaceous period between 110 and 130 million years ago and diversified after the rise of flowering plants. More than...
belonging to the Iridomyrmex
Iridomyrmex
Iridomyrmex is a genus of ants that belongs to the subfamily Dolichoderinae. There are 79 species and subspecies that belong to this genus and they range from India to China to Australia and New Caledonia.-Description:...
genus. They can be found throughout Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
.
Nests
The use of different parts of the nests is largely dependent on environmental factors, for example excessive shading of the main mound will stimulate the occupation of different parts of the nest or the expansion of satellite colonies.
Meat ants cover their nest mounds with gravel
Gravel
Gravel is composed of unconsolidated rock fragments that have a general particle size range and include size classes from granule- to boulder-sized fragments. Gravel can be sub-categorized into granule and cobble...
, sand
Sand
Sand is a naturally occurring granular material composed of finely divided rock and mineral particles.The composition of sand is highly variable, depending on the local rock sources and conditions, but the most common constituent of sand in inland continental settings and non-tropical coastal...
, leaf petiole
Petiole (botany)
In botany, the petiole is the stalk attaching the leaf blade to the stem. The petiole usually has the same internal structure as the stem. Outgrowths appearing on each side of the petiole are called stipules. Leaves lacking a petiole are called sessile, or clasping when they partly surround the...
s, twigs, seed capsules, mollusk shells and other small items, which heat the nest quicker in the morning.
Foraging
Omnivore
Omnivores are species that eat both plants and animals as their primary food source...
scavengers that get their name from their use, by farmers, to clean carcasses. Meat ants are diurnal. On hot days foraging is bimodal, with all activity ceasing during the heat of the day.
Like other Iridomyrmex species, they engage in a mutualistic relationship with certain caterpillar
Caterpillar
Caterpillars are the larval form of members of the order Lepidoptera . They are mostly herbivorous in food habit, although some species are insectivorous. Caterpillars are voracious feeders and many of them are considered to be pests in agriculture...
s and butterflies
Butterfly
A butterfly is a mainly day-flying insect of the order Lepidoptera, which includes the butterflies and moths. Like other holometabolous insects, the butterfly's life cycle consists of four parts: egg, larva, pupa and adult. Most species are diurnal. Butterflies have large, often brightly coloured...
of specific species which produce secretions that meat ants will feed on. In return, they protect the caterpillars from predation
Predation
In ecology, predation describes a biological interaction where a predator feeds on its prey . Predators may or may not kill their prey prior to feeding on them, but the act of predation always results in the death of its prey and the eventual absorption of the prey's tissue through consumption...
. Honeydew collected from hemipterous insects
Hemiptera
Hemiptera is an order of insects most often known as the true bugs , comprising around 50,000–80,000 species of cicadas, aphids, planthoppers, leafhoppers, shield bugs, and others...
is the main component of the diet of most meat ant colonies. This is supplemented by scavenging for dead invertebrate
Invertebrate
An invertebrate is an animal without a backbone. The group includes 97% of all animal species – all animals except those in the chordate subphylum Vertebrata .Invertebrates form a paraphyletic group...
s.
Behaviour
Meat ants do not have dedicated soldier and worker castes like some ants. Instead they exhibit age caste polyethismTask allocation and partitioning of social insects
Task allocation and partitioning refers to the way that tasks are chosen, assigned, subdivided, and coordinated . Closely associated are issues of communication that enable these actions to occur....
, meaning that they take on different roles in the colony at different ages. Young ants care for eggs and larvae in the nest. Older ants form part of large foraging parties to exploit significant stationary food resources, such as a dead animal or a colony of hemipterous insects. Older ants undertake lone foraging across open ground, predominately collecting invertebrates and 'building material.' The oldest ants are involved in inter-colony competition.
Meat ants exhibit aggressive competitive interaction with other species of ants and are therefore a dominant component of Australian ant communities. Other species employ strategies that exploit resources or habitats not favoured by meat ants, or forage at alternate times (like the common crepuscular Camponotus species). They are aggressive towards meat ants from neighbouring colonies. Old workers engage in ritual combat along borders between colonies to establish foraging boundaries. Like many other species of ant, meat ants are able to communicate with one another using chemical cues.
Cane toads
Recently it has been found that meat ants are able to kill poisonous cane toadCane Toad
The Cane Toad , also known as the Giant Neotropical Toad or Marine Toad, is a large, terrestrial true toad which is native to Central and South America, but has been introduced to various islands throughout Oceania and the Caribbean...
s, an introduced pest
Invasive species
"Invasive species", or invasive exotics, is a nomenclature term and categorization phrase used for flora and fauna, and for specific restoration-preservation processes in native habitats, with several definitions....
, as the toxins that usually kill a cane toad's predator do not affect the meat ants. The cane toad's normal response to attack is to stand still and let their toxin kill the attacker, which allows the ant to attack and eat the toad.
External links
- Australian Ants Online page about meat ants.