A note about The Cuddlywumps Chronicles

This blog is written and maintained by Miss Cuddlywumps, a fluffy-tailed calico cat who is both classically educated and familiar with mysteries. Comments or complaints should be addressed to Miss C rather than to author Roby Sweet. Ms. Sweet accepts no responsibility for Miss C's opinions.

Friday, July 3, 2015

How Long Did It Take for a Saber-Toothed Cat to Grow Its Saber Teeth?



We are reaching deep into feline history today, all the way back to the Pleistocene epoch (2.5 million to 11,500 years ago, give or take), to learn something about our long-lost cousin the saber-toothed cat (that’s Smilodon fatalis if you want to be scientific). Why? Well, because, thanks to a new study, we now know how long it took these animals to grow their huge canine teeth, and we think that's pretty interesting.


Here, kitty kitty—not!
Saber-toothed cat illustration on signage at the
Cincinnati Museum of Natural History & Science,
Cincinnati, Ohio.
Photo by James St. John
[CC BY 2.0], via Wikimedia Commons. 

A bit about the saber-toothed cat

Saber-toothed cats lived in North America and parts of South America until they went extinct 13,000 years ago. They probably weighed from 350 pounds to just over 600 pounds and stood nearly 40 inches tall at the shoulder. Oh, and those teeth we’re so interested in could be seven inches long and were serrated on both edges. (This is not a cat you’d want to have napping on your couch.)


Saber-tooth cat skull at the
Regional Museum of Guadalajara
in Guadalajara, Mexico.
Photo by Thelmadatter (Own work)
[Public domain], via Wikimedia Commons.

Growing those saber teeth

Perhaps not surprisingly, it took a while for those big canine teeth to fully erupt, or push through the gums. According to a brand-new study using fossils from Rancho La Brea in southern California, permanent canine teeth began to erupt when saber-tooth cubs were between one and one and a half years old. The teeth erupted at about six millimeters (just under a quarter of an inch) per month, faster than the rate for modern lions, and a little more than half as fast as human hair grows.

At that rate, the saber teeth weren't fully erupted and at full size until the cats were about three years old.

To give you a little perspective, modern domestic cats have all their adult teeth ready to go when they’re about six months old.

Baby canines and adult sabers side by side

The saber-tooth’s baby (or deciduous) canines finished erupting when the cat was about a year to a year and half old (the same time the adult sabers began to erupt). Then, as the permanent saber teeth erupted, the baby teeth remained in place for almost a year, possibly to keep the saber teeth from being broken.

Young saber-tooth cubs rare at Rancho La Brea

Using the tooth data to estimate ages of saber-toothed cats found at Rancho La Brea, the researchers found that cubs under four to seven months old were rarely preserved there. This makes sense when you consider that those younger cubs wouldn’t have had fully erupted baby canine teeth yet. Until they were well-equipped for defense, the cubs were probably kept closer to the den to keep them away from predators.

For more on prehistoric cats, see Meet the Cat of All Cats: He's 25 Million Years Old.

Sources

Wysocki MA, Feranec RS, Tseng ZJ, Bjornsson CS (2015) Using a Novel Absolute Ontogenetic Age Determination Technique to Calculate the Timing of Tooth Eruption in the Saber-Toothed Cat, Smilodon fatalis. PLoS ONE 10(7): e0129847.

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