Info from Wikipedia:

This myth was born from the stories of dolphins protecting shipwrecked sailors from sharks. The Mythbusters built an animatronic replica of a dolphin and took it to the shark infested waters of South Africa. They tested the waters by throwing in a seal-shaped lure only to have it attacked by a great white shark just barely five seconds after it hit the water. They then placed the fake dolphin in the water with the lure. The sharks approached the lure, but when they saw the dolphin, opted not to attack. The Mythbusters replaced the lure with actual bait, but the results were the same, and the sharks appeared reluctant to attack. However, once they removed the dolphin, the sharks immediately began attacking the lures and bait again. With these results and with plenty of ancedotal evidence, the Mythbusters decided that the myth was plausible.

Being that a shark is cold blooded and operates on feeding by means of short bursts of energy. A probable explanation for their unwillingness to go toe-to-toe (fin-to-fin) with an animal such as the dolphin that has far more stamina and rarely travels alone is a simple case of risk assessment and conservation of energy on the shark's behalf.

...there's plenty of other fish in the sea

I don't trust anything that breaths from an asshole in the top of its head.

*nature

Adding video to channels (Nature) - requested by ant.

"help the helpless"... Altruism. Pure altruism is giving without regard to reward or the benefits of recognition.

Gotta love dolphin! Way to go, my atheist little cousin

This must be the crappiest and most unreliable test these guys have ever done.

Does that mean you don't trust me, qualm?

for that definition of altruism...

...what about the personal feeling of reward coming from your brain's chemical reward system by means of dopamine? Does that count as a reward? Would anybody be altruistic without this reward system?

i thought sharks relied on smell and hearing rather than sight. not sure a shark would find an animatronic dolphin very appetizing.

the dopamine "reward" systemis not always what makes people do altruistic things. If I've already eaten and I opt to make diner for the family, trust me, I'm not getting any kind of "good feeling" or dopamine; I'm doing my responsibility. The dopamine "reward" system is only in place for things you don't normally do or are new to you; over time and repetition, the surge of dopamine is no longer necessary for the person to perform the task. Otherwise we'd constantly be doing "altruistic" things whether they needed to be done or not.
Sorry, it's a pet peeve of mine when people try that whole "there is no such thing as altruism" argument; it's fallacious. People actually do perform unpleasant tasks merely because it is "right" or their perceived resonsibility. THere isn't always a good feeling to spur them on. Ask any parent of a newborn on the second week of 2am feedings and diaper changes.

sillma, care to propose a better one?

*dead

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