The study authors supply plausible and completely ordinary explanations for weight gain in each of the populations. Why speculate beyond that? No reason excep

The study authors supply plausible and completely ordinary explanations for weight gain in each of the populations. Why speculate beyond that? No reason except that it's "intriguing." Though it is certainly not necessary that there be a single explanation for all of these population level increases nor even a single explanation for each individual population, it is intriguing to consider whether there are any factors that could conceivably account for weight increases in all of these populations. In other words, just more fuel for speculation about some alien contaminant, a pathogen or pollutant, that we can blame for the obesity epidemic. We have all the explanations for human obesity that we could possibly need, but we continue to wish for some cause that does not operate through our behavior.