Major categories of pit viper venom

Despite these categories, the clinical impacts on human morbidity and mortality are not what one would necessarily predict . Why? It’s not clear? Perhaps the Mojave Rattlesnake is not as deadly as venom analysis would suggest? Maybe the bites differ from predation to defense? Maybe there are differences in human biology? Possibly, it’s a combination of factors? Who knows; but an interesting area for future research.