Thursday, December 2, 2010

Younger White Sharks, Weak Jawed or Weak Willed?

The Nano Patents and Innovation Blog (yup, it exists) has an interesting look at sub adult white shark predation and the current thought about "one bite predation" in this group.

It's been long known that most white shark attacks on humans are "one bite affairs" that rarely lead to death, unless the target is unfortunate enough to have an artery severed.

Today's post in the NPI suggests that sub adult white sharks lack the actual jaw strength to complete a successful predation hence the one bite attacks.

Interesting stuff.

I have seen enough "repeated attacks" on the target prey species of sub adult white sharks to offer another analysis.

Weak Jawed or Weak Willed?

It would seem to me with millions of years of evolution behind them, white sharks go though a guided predatory evolution as they transition between sub adult and adult phases. It's a learning curve that is reward based. If the bite is successful, i.e something in the bite process fires off the evolutionary neurons in the sharks brain that says "aha, food" the attack continues. We see this with tuna and white sharks world wide. Even deeply frozen tuna that is as hard as granite.

If, on the other hand, the attack hits a surf board, or beer can, or floating seagull, those same neurons come into play and the attack becomes a "one bite affair".

Dr. Peter Klimley at California's U.C Davis spent years at the Farallone islands in the 80's testing this same hypothesis. Reward based predation.

While my analysis is based on years of face to face observations with white sharks using baits and decoys, I would lean towards an evolutionary process that guides the "one bite" sub adult conversation. Jaw strength might have something to do with it, but is it the driver?

As anyone who has been fortunate enough to watch sub adult white sharks savage an 80lb frozen tuna carcass will tell you, once the evolutionary tumblers in a white sharks brain have fallen into place, these magnificent predators are not to be deterred and weak jaw or not, they are in it to finish it.


Patric Douglas CEO

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