Mating in D. hominis begins with "pouncing" displays performed by a male in response to sexual readiness in a female, which is indicated by the protraction of the latter's abdomen or pseudovipositor. Copulation is normally contingent upon female receptiveness; in other words, females seem to exhibit behavior suggestive of mate choice. Laboratory experimentation has revealed that males can pair with multiple mates in the average ratio of 1 male to 2.8 females. Perhaps due to the polygynous mating system, competition among males has been observed in the form of "pouncing" disturbances directed at copulating pairs. Copulation terminates after about 9 minutes.
Mating System: polygynous
Dermatobia hominis exhibit a homometabolous life-cycle. Being non-feeding and having a short adult life span (3-4 days in the laboratory), this stage in the life-cycle of D. hominis is allocated primarily towards reproductive efforts. Females lay 800 to 1,000 eggs.
Unique from other bot-fly species, which lay their eggs directly on the host or in the host's environment, is the peculiar egg dispersal strategy exhibited by females of the human bot fly; this process involves the use of porters (i.e., paratenic hosts) as vectors for transporting eggs onto the bodies of the vertebrate hosts. Under this strategy, a female captures a porter and glues her eggs onto one side of its abdomen using a water-insoluble glue, after which the porter is released without being harmed. Being sensitive to a sudden rise in temperature, the eggs instantly hatch upon contact with the warm-blooded body of a definitive host as the porter lands onto it, usually to feed on blood. Within 5-10 minutes, the larvae bore their way into the definitive host's body, often via the wounds inflicted by the porter's feeding, and establish themselves in the subcutaneous layer. Forty-eight species of flies--of which about half are mosquitoes--and a tick are reported to be involved in this paratenic relationship with female D. hominis. Porter species are often zoophilous, diurnal, moderate in size, and not too active. Potential advantages of this egg dispersal strategy include the protection of eggs from the elements and egg-parasitism, the prevention of egg loss from host grooming, and the adaptive allocation of energy in reproductive efforts.
Range eggs per season: 800 to 1000.
Key Reproductive Features: semelparous ; sexual ; fertilization (Internal ); oviparous
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