This kinda makes sense. For a rabbit or fly, food is plentiful and the biggest threat to your survival is predators, so it makes sense to have loads of offspring in the hope that some will survive. For a lion, predators are nonexistent but the biggest threat to survival is lack of food, so if you have too many children in the same territory you run the risk that they'll all starve.

Exception that "proves" the rule: frogs are incredibly fecund predators, but tadpoles are herbivores.

Hmm, I guess I'm forgetting spiders.

Another explanation could be that the decision to maintain physical strife, whether it was made consciously or not, could be the thing that has rescued their gene pool from wussification by their reliance on tech.

Apart from that, I wonder if this article's analyst would draw the same conclusion about a subculture that values suicide bombing?