Is there any way to determine the age of sharks?

It is necessary to establish a test program to determine the age of different kinds of fish according to intact or segmented vertebrae or other calcified parts (such as segmented vertebrae appearing in some cartilage groups). In addition, for different kinds of sharks, the visible growth increment area on the fish spine needs chemical staining and/or special illumination or X-ray micrograph to estimate and analyze the age of the fish.

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