Growing fangs

On a recent visit to the George C. Page Museum, better known as Rancho La Brea, I examined a series of sabertooth skulls (Smilodon fatalis).

[milk teeth of a very young baby sabertooth]

In an ongoing effort to calculate the growth rate of the elongate upper canine of this species, I am working with Dr. Robert Feranec of the New York State Museum on correlating degree of tooth eruption versus enamel isotopic signals of growth. We are re-examining a growth series of sabertooth specimens originally described by Chris Shaw, the resident carnivore man at Rancho La Brea.

[another young individual, with some tooth wear]

By measuring the canine length erupted and the location of the line of enamelization, we could then calculate the rate of enamel deposition by dividing the metric differences in enamel length between young and older individuals by the already analyzed duration represented per unit enamel length acquired from isotope studies.

[a young sabertooth with fully erupted milk dentition]

Then, with an assumption of identical rates of growth between tooth eruption and enamelization, we could estimate the total time it took for the complete growth of an adult sabertooth canine.

[a specimen showing replacement of milk dentition by permanent teeth]

The calculations and measurements are still underway! Stay tuned for our results.

[a full adult Smilodon fatalis, with a saber measured at 163 millimetres (6.4 inches)!]