page_title: Myrmecia (ant)
section_title: Life cycle
hierarchical_section_title: Myrmecia (ant) / Behaviour and ecology / Life cycle
caption_attribution_description: English: Red Bull Ants in dark at Sydney Wildlife World
context_page_description: Myrmecia is a genus of ants first established by Danish zoologist Johan Christian Fabricius in 1804. The genus is a member of the subfamily Myrmeciinae of the family Formicidae. Myrmecia is a large genus of ants, comprising at least 93 species that are found throughout Australia and its coastal islands, while a single species is only known from New Caledonia. One species has been introduced out of its natural distribution and was found in New Zealand in 1940, but the ant was last seen in 1981. These ants are commonly known as "bull ants", "bulldog ants" or "jack jumper" ants, and are also associated with many other common names. They are characterized by their extreme aggressiveness, ferocity, and painful stings. Some species are known for the jumping behavior they exhibit when agitated.
  Species of this genus are also characterized by their elongated mandibles and large compound eyes that provide excellent vision. They vary in colour and size, ranging from 8 to 40 millimetres. Although workers and queens are hard to distinguish from each other due to their similar appearance, males are identifiable by their perceptibly smaller mandibles.
context_section_description: Like other ants, Myrmecia ants begin as an egg. If the egg is fertilised, the ant becomes a diploid female; if not, it becomes a haploid male. They develop through complete metamorphosis, meaning that they pass through larval and pupal stages before emerging as adults.
  During the process of founding a colony, as many as four queens cooperate with each other to find a suitable nesting ground, but after the first generation of workers is born, they fight each other until one queen is left alive. However, occasional colonies are known to have as many as six queens coexisting peacefully in the presence of workers. A queen searches for a suitable nest site to establish her colony, and excavates a small chamber in the soil or under logs and rocks, where she takes care of her young. A queen also hunts for prey instead of staying in her nest, a behaviour known as claustral colony founding. Although queens do provide sufficient amounts of food to feed their larvae, the first workers are "nanitics" (or minims), smaller than the smallest workers encountered in older developed colonies. Several species do not have any worker caste, and solitary queens will raid a colony, kill the residing queen, and take over the colony. The first generation of workers may take a while to fully develop into adults; for example, M. forficata eggs take around 100 days to fully develop, while other species may take up to eight months.
  Queens lay around eight eggs, but less than half of these eggs develop. Some species, such as M. simillima and M. gulosa, lay their eggs singly on the colony floor, while M. pilosula ants may lay eggs in a clump. These clumps have  two to 30 eggs each with no larvae present. Certain Myrmecia species do not lay their eggs singly and form clumps of eggs, instead. The larvae are capable of crawling short distances without the assistance of adult workers, and workers will cover the larvae in dirt to help them spin into a cocoon. If cocoons are isolated from a colony, they are capable of shedding their skins before hatching, allowing themselves to advance to full pigmentation. Sometimes, a newborn can emerge from its pupa without the assistance of other ants. Once these ants are born, they are able to identify distinct tasks, a well known primitive trait. Myrmecia lifespans vary in each species, but their longevity is greater than many ant genera: M. nigrocincta and M. pilosula have a lifespan of one year, while M. nigriceps workers can live up to 2.2 years. The oldest recorded worker was a M. vindex, living up to 2.6 years. If a colony is deprived of workers, queens are able to revert to colony-founding behaviours until a sustainable workforce emerges. A colony may also emigrate to a new nesting spot altogether.
caption: Captive colony with pupae
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