Density of subjects

The dose-lethality relation typically is determined after submitting small groups of caged subjects to doses of a toxin. Sautet et al. (1968) indicated that the susceptibility to DDT increased positively with the number of caged mosquitoes, thus suggesting that individuals within a treatment group are not independent. For honey bees where social interactions occur, Dechaume-Moncharmont et al. (2003) concluded that “bees do not die independently of each other” for a continuous chronic exposure.