Table 1. Summary of samples used for experimental analyses.

Procedure	Sample size
Gross morphology	20 fish per age group
Radiography	4 x 1 year fish, 3 x 2 year fish, 5 x 3 year fish	Low power imaging of whole spines; high power imaging of cervical and trunk regions
MicroCT	3 fish per age group for each separate analysis	3 replicates (cervical vertebrae)
Histology		Serial sagittal sections (whole spines)
Electron Microscopy		Ultrathin sections at 3 different depths (cervical vertebrae)
Immunohistochemistry		3 replicates (mid-sagittal sections of whole spines)
RPIP-HPLC		3 replicates (whole spines)

RPIP-HPLC, Reverse Phase Ion Pair-High performance liquid chromatography.