The Ecological Determinants of Population Growth in a Drosophila Culture. V. The Adult Population Count

Abstract

The logistic law has usually been applied, not to true population growth, but to "family growth" in the normal Drosophila culture. Even the adult counts for this limited phase are not adequately described by the logistic and they are readily altered by changing the culture conditions (brand of yeast used, addition of Nipagin to the medium, presence of moulds, etc.). The amt. of medium used determines the total yield of the cultures, but the amt. of yeast seeded has little effect within the range tested. How far the adult count may be taken as an index of the complex interaction occurring between the developing larvae and yeasts in a culture, is discussed in the light of earlier papers in the series.