few comments. Omega 3's were more prevalent in Paleolithic diets since we ate more seeds and the animals we ate only ate other animals, seeds and grasses unlike the grain fed livestock today.
We need more omega 3's today due to the high refined carbo diet (omega 3's activate PPARs which help reduce insulin resistance) and we need them to compete with the high level of omega 6's. The 3's and 6's compete in the body in generating different prostaglandins (the 3's are anti-inflammatory and vasodilatory and the 6s are the opposite).
www.OmegaBrite.com is a source of super pure incredibley high EPA fish oils. It is owned by a pair of Harvard docs.