The Intrinsic Rate of Natural Increase for the Human Louse, Pediculus humanus L.
1952; University of Chicago Press; Volume: 86; Issue: 830 Linguagem: Inglês
10.1086/281737
ISSN1537-5323
AutoresFrancis C. Evans, Frederick E. Smith,
Tópico(s)Entomological Studies and Ecology
ResumoData on mortality, fecundity, and duration of life history stages were obtained for lice kept in uncrowded colonies at a temperature of approximately 30⚬ C. and at a relative humidity which varied between 30 and 55 per cent. Under these conditions the intrinsic rate of natural increase, that is, the rate of increase per head in a population which has attained a stable age distribution, was calculated to be 0.111 per day for Pediculus humanus. In this population, one female egg alive would on the average be replaced by 30.93 live daughter eggs, and 6.24 days would be required for the population to double in numbers. A comparison of vital statistics with those already published for two species of graminivorous insects and two species of rodents, all of which are assumed to have been obtained under conditions conducive to maximum rates of growth, suggests that the natural environment of the individual human louse is a remarkably safe one.
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