Parents screamed, children cried and I looked on in horror at the scene unraveling around me in the Shamu tank at the San Diego Sea World in February 2010.

Death was up to his usual tricks.

The stadium was packed and the trainers were putting the whales through their paces. Birds circled above, eyeing the fish the trainers were using as rewards for Shamu and his pals performing their tricks

But then, a lone brown pelican, about the size of a poodle, landed on the far side of the tank to take advantage of the bounty.

The trainers didn’t notice. But Shamu did.

In an instant, Shamu dove under the water, swam up under the bird, opened his mouth and, with a splash, dragged it down. The trainers realized what happened when the carcass floated to the surface and the whales began fighting over the prize. They immediately stopped the show.

Instinct had trumped training, and Shamu was sent for the killer whale equivalent of a time-out.

A week later at Sea World in Florida, instinct won over conditioning yet again. Only this time, the victim was a female trainer. According to news sources, while the trainer lay down in a shallow area leading into the tank, her ponytail was floating and attracted the whale’s attention. And, as like with the pelican, the whale sought to explore with the only tactile source available: his teeth.

The allegations against the whale were horrible, calling it malicious or evil, and that the whale somehow planned the attack as an act of revenge

But it was not a meticulously thought out plan for revenge, the whale just did what came natural. The whale reacted, and all the training in the world could not override millions of years of evolution.

The whale was trained using a method known as operant conditioning through positive reinforcement, pioneered by the famous American psychologist B.F. Skinner.

Skinner used what is known as a "Skinner Box" to train lab rats and pigeons to learn certain behaviors.  He would place the animal in a box with two buttons: one that brought food, and the other did nothing.

Positive reinforcement occurs when a specific behavior, such as pressing a button, results in a reward, which then reinforces that behavior to occur again and again until it becomes ingrained in the animal’s mind. That is how the whales are trained at Sea World, except that once the trick is learned through positive reinforcement, it is then paired with some sort of gesture, like a hand movement.  This allows the trainers to dictate what trick the animals will perform throughout the show, without the audience being aware, while allowing the animal to perform the required trick to earn its treat.

The process is repeated daily for weeks or months to make the response so ingrained into the animal's personality, that the behavior becomes simply second nature.

And that’s the key: second nature.

The fact is, no matter how well you train an animal to behave, you cannot possibly override its natural instinct. Dogs will still bite, cats will still scratch, and animals that hunt will continue to kill.

Animals are, regardless of how well they are trained, still wild animals, and care should be taken whenever they interact with people. And I know that more than most.

I’ve been bitten by snakes and dogs, clawed at by an owl, pecked at by birds, scratched by cats, almost mauled by an angry crocodile and almost lost a hand to a snapping turtle as big as a truck tire.

Instinct and evolution will always trump behavior and conditioning.

All it takes is time.