Myers P, Lundrigan B L, Gillespie B W, Zelditch M L
Museum of Zoology, University of Michigan, Ann Arbor 48109, USA.
J Morphol. 1996 Aug;229(2):229-37. doi: 10.1002/(SICI)1097-4687(199608)229:2<229::AID-JMOR7>3.0.CO;2-W.
Morphologists and systematists have long suspected that dietary consistency can affect skull and dental form in mammals. We examined plasticity of skull shape and tooth morphology in prairie deer mice (Peromyscus maniculatus bairdii) by feeding mice diets that differed in consistency but not nutritional quality. Shape differences were analyzed qualitatively and quantitatively, using both landmark-based morphometrics and traditional distance measurements. Mice fed a gruel made of laboratory chow soaked in water differed from those fed hard blocks of chow by a slight anterior shift in the incisor tips, a narrowed zygomatic plate, a reduction in size of the masseteric tubercles, an overall decrease in skull size in lateral view, and an increase in overall size in ventral view. Disparities between our results and previous studies may be due to the differences in behavior between the inbred, relatively inactive laboratory strains commonly used in experimental studies and the outbred, constantly active species used here. Also, in contrast to previous studies, the statistical analysis employed here took into account both family relationships of the animals and the large number of statistical comparisons performed. Failure to consider these factors would have resulted in an exaggerated estimate of the effects of diet on skull form and may taint other studies that have explored the same aspects of plasticity.
形态学家和分类学家长期以来一直怀疑饮食的一致性会影响哺乳动物的头骨和牙齿形态。我们通过给草原鹿鼠（白氏鹿鼠）喂食质地不同但营养质量相同的食物，研究了其头骨形状和牙齿形态的可塑性。使用基于地标点的形态测量法和传统距离测量法，对形状差异进行了定性和定量分析。喂食用水浸泡过的实验室饲料制成的稀粥的小鼠，与喂食硬饲料块的小鼠相比，上门齿尖端略有向前移位，颧板变窄，咬肌结节尺寸减小，从侧面看头骨整体尺寸减小，从腹面看整体尺寸增大。我们的结果与先前研究之间的差异可能是由于实验研究中常用的近交、相对不活跃的实验室品系与这里使用的远交、持续活跃的物种之间的行为差异。此外，与先前的研究不同，这里采用的统计分析考虑了动物的家族关系以及进行的大量统计比较。不考虑这些因素会导致对饮食对头骨形态影响的估计过高，并可能影响其他探索可塑性相同方面的研究。
