Fig 1.
Beluga tooth basic histology and Growth Layer Groups.
(A), half tooth (2014LDL8T4), cut longitudinally and polished, GLGs marked with white double-headed arrows in magnified view delimited by red box; (B), ground section (2014LDL8T3) with histological features labeled; (C-D), demineralized sections (2012LDL8T2), GLGs marked with yellow double-headed arrows; (C), stained with Mayer’s hematoxylin; (D), and Bielschowsky’s silver stain.
Table 1.
Specimen information and tabulated measurements.
Fig 2.
(A-D), daily incremental lines (yellow arrows) in beluga dentin. (A), incremental lines following the contours of calcospheres (c), demineralized section (2012LDL8T2), Bielschowsky’s silver stain, monotone photomicrograph; (B), ground section (2014LDL8T3), differential interference contrast, monotone photomicrograph; (C), Incremental lines and dentin tubules (white arrows) demineralized section (2012LDL3T6), Mayer’s hematoxylin, monotone photomicrograph; (D), Incremental lines demineralized section (2012LDL8T2), Bielschowsky’s silver stain, monotone photomicrograph.
Table 2.
Estimated and predicted values.
Fig 3.
(A), distribution of short-period incremental lines plotted against distance from start of the GLG (2012LDL8-c); (B), mean incremental line spacing (triangles) plotted against GLG width, error bars show 3σSE, solid red line represents expected spacing if GLG represents one year (1GLG/yr), solid blue line represents the expected spacing if two GLGs are deposited in a year (2GLG/yr), green diamond shows the mean of all seven GLGs; (C), estimated number of days represented in each GLG, solid lines represent expected number of days for 1GLG/yr and 2GLG/yr, green diamond shows the mean of all seven GLGs.