Transmission of Susceptibility to Carbon Dioxide to Species Hybrids in Drosophila

Abstract

L'Héritier and Teissier¹ have described a stock of Drosophila melanogaster the flies of which die when exposed for five minutes to carbon dioxide at temperatures between 1° and 23° C., whereas other flies of the species recover from such treatment after a few minutes². This susceptibility, $s_{{\text{CO}}_{\text{2}}}$, or its normal counterpart, resistance to carbon dioxide, is transmitted to the offspring as one unit, but it is not fixed to any of the chromosomes and therefore cannot be regarded as a Mendelian character. In crosses between flies from L'Héritier's stock and normal flies, susceptibility to carbon dioxide is transmitted to the whole offspring by the mother, but only to part of the offspring by the father. Some of the latter's susceptible daughters, but not the sons, may in turn transmit it to their offspring. No individual resistant to carbon dioxide has been observed to transmit susceptibility.