Hewitt J K, Fulker D W, Hewitt C A
J Comp Psychol. 1983 Mar;97(1):52-8.
Recent claims to have demonstrated associative learning ability in Drosophila melanogaster raise questions about the adaptive significance of behavioral modifiability of this species. In a strain survey and a 9 X 9 half diallel cross study of olfactory discriminative avoidance conditioning, a low narrow heritability and strong directional dominance or heterosis controlling nonrandom phenotypic variation were found. Furthermore, the predicted inbreeding depression and asymmetrical response to bidirectional genetic selection were both observed. The genetic architecture revealed in these experiments is consistent with a close association between this conditioning phenotype and evolutionary fitness. Predictions from this interpretation to the nature of new mutations have been confirmed, and a possible role for conditioning in courtship behavior has been identified.
最近宣称已在黑腹果蝇中证明其具有联想学习能力，这引发了关于该物种行为可变性的适应性意义的问题。在一项嗅觉辨别回避条件反射的品系调查和9×9半双列杂交研究中，发现了较低且狭窄的遗传力以及控制非随机表型变异的强烈定向显性或杂种优势。此外，还观察到了预测的近亲繁殖衰退以及对双向遗传选择的不对称反应。这些实验中揭示的遗传结构与这种条件反射表型和进化适应性之间的紧密关联是一致的。从这种解释对新突变性质的预测已得到证实，并且已确定条件反射在求偶行为中的一种可能作用。
