Bones in the vertebrate cranial base and limb skeleton grow by endochondral ossification, under the control of growth plates. Mechanisms of endochondral ossification are conserved across growth plates, which increases covariation in size and shape among bones, and in turn may lead to correlated changes in skeletal traits not under direct selection. We used micro-CT and geometric morphometrics to characterize shape changes in the cranium of the Longshanks mouse, which was selectively bred for longer tibiae. We show that Longshanks skulls became longer, flatter, and narrower in a stepwise process. Moreover, we show that these morphological changes likely resulted from developmental changes in the growth plates of the Longshanks cranial base, mirroring changes observed in its tibia. Thus, indirect and non-adaptive morphological changes can occur due to developmental overlap among distant skeletal elements, with important implications for interpreting the evolutionary history of vertebrate skeletal form.

中文翻译：

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通过平行改变发育机制来选择增加小鼠胫骨长度的方式来改变颅骨形状

脊椎动物颅底和四肢骨骼中的骨骼通过软骨板的骨化作用在生长板的控制下生长。软骨板骨化的机制在整个生长板中均保持不变，这增加了骨骼之间大小和形状的协变，进而可能导致骨骼特征的相关变化，而不是直接选择。我们使用micro-CT和几何形态计量学来表征Longshanks小鼠颅骨的形状变化，这是有选择地繁殖的更长胫骨。我们显示，Longshanks头骨在逐步的过程中变长，变平和变窄。此外，我们表明，这些形态变化可能是由于长柄颅底生长板的发育变化引起的，反映了其胫骨中观察到的变化。因此，