Institut für Zoologie, Rheinische Friedrich-Wilhelms-Universität Bonn, Poppelsdorfer Schloss, 53115 Bonn, Germany.
Abteilung Paläontologie, Institut für Geowissenschaften, Rheinische Friedrich-Wilhelms-Universität Bonn, Nussallee 8, 53115 Bonn, Germany.
Proc Biol Sci. 2021 Jul 28;288(1955):20211166. doi: 10.1098/rspb.2021.1166. Epub 2021 Jul 21.
Histology-based skeletochronology is a widely used approach to determine the age of an individual, and is based on the assumption that temporal cessations or decelerations of bone growth lead to incremental growth marks (GM), reflecting annual cycles. We studied the reliability of histology-based skeletochronology in a variety of extant tetrapods by comparing two different approaches: petrographic ground sections versus stained microtomized sections. Each bone was cut into two corresponding halves at its growth centre in order to apply both approaches to one and the same sample. None of the samples unequivocally revealed the actual age of the specimens, but truly concerning is the fact that the majority of samples even led to conflicting age estimates between the two approaches. Although the microtomized sections tended to yield more GM and thus indicated an older age than the ground sections, the contrary also occurred. Such a pronounced ambiguity in skeletochronological data strongly challenges the value of the respective age determinations for both extant and extinct animals. We conclude that much more research on the fundamental methodological side of skeletochronology-especially regarding the general nature and microscopic recognition of GM-is required.
组织学骨骼年代学是一种广泛用于确定个体年龄的方法，其基于这样的假设，即骨骼生长的暂时停止或减速会导致递增生长标记（GM），反映出年度周期。我们通过比较两种不同的方法——岩相学地面切片与染色微切片——来研究现生四足动物组织学骨骼年代学的可靠性。为了将两种方法应用于同一个样本，每个骨骼在生长中心被切成两半。没有一个样本明确揭示了标本的实际年龄，但更令人担忧的是，大多数样本甚至导致两种方法之间的年龄估计相互矛盾。尽管微切片往往产生更多的 GM，因此表明比地面切片更老的年龄，但反之亦然。骨骼年代学数据中的这种明显的模糊性强烈挑战了对现生和已灭绝动物的相应年龄测定的价值。我们得出结论，需要对骨骼年代学的基本方法学方面进行更多的研究，特别是关于 GM 的一般性质和微观识别。
