We all know about global warming, and we all want to save the planet. The average person on the planet is responsible for about four tons of carbon dioxide emissions per year, for a total of about 25 gigatons (thousand billion tons) (http://timeforchange.org/CO2-emissions-by-country). Seems like a lot.
Surprisingly, however, although it gets almost all of the press, maybe carbon dioxide emissions aren’t the biggest problem. Consider the cow, which burps and farts huge quantities of methane, a much more powerful greenhouse gas than carbon dioxide.
A United Nations report concluded that “the livestock sector generates more greenhouse gas emissions as measured in carbon dioxide equivalent than transport.” (http://change.nature.org/2011/04/01/no-fooling-cow-burps-and-farts-contribute-to-climate-change/) Yes, eating those MacBurgers might be worse for the environment than driving that SUV. As Robin says to Batman, “Holy Cow!”
To better understand the problem we have to dig deep into the bowels of the subject. Amazingly, it turns out that people have about ten times more bacterial cells than human cells. What?? Yes, it is true (http://www.sciencedaily.com/releases/2008/06/080603085914.htm). Bacterial cells are very small, and our guts are crammed full of them. So, in the end, each of us actually has far more bacterial cells than people cells. The same sort of ratio is also true for cows. Like us, they are loaded with bacteria.
And therein lies the rub. The bacteria are very useful for the cows, converting otherwise worthless plant material into functional food. Unfortunately this fermentation process creates methane. A quick look at the fart chart shows that California tops the list, producing about 350,000 tons of methane a year, with Wisconsin coming in at number two (http://milk.procon.org/view.resource.php?resourceID=001154#methodology).
And how can we solve this problem? Researchers in Argentina have connected gas bags to cows, finding that each one produces around a thousand liters a day http://www.dailymail.co.uk/sciencetech/article-1033656/Reducing-cow-burping-key-tackling-climate-change.html. If we could only harvest this energy source to power our cities! Alas, this seems unlikely.
Some studies have suggested that a change of diet could help. Less Mexican and more Beano? Or, maybe just more alfalfa and clover.
Of course one option would be for us all to go vegan. Just stop eating cows and drinking their milk. There are some reasons to think this might be the best route. Cows are mammals like us, and have almost the same set of genes. From an evolutionary perspective eating a cow is sort of like eating your cousin. But, darn it, they taste so good!
Thank heaven there has recently been a major breakthrough in cow fart research. It turns out that kangaroos are relatively methane free. So maybe we should kill the cows and switch to roos. But there could be some nasty consequences. Imagine enormous numbers of kangaroos jumping over fences, crashing into cars, and creating massive carnage. No, there must be a better way.
It turns out that marsupials have different bacteria in their guts, that produce succinate as a by product instead of methane (http://news.sciencemag.org/sciencenow/2011/06/scienceshot-why-wallabies-dont.html?etoc&elq=5629ef59290a47bd9fa324c28c66377c). So all we need to do is convert the population of bacteria in the cow gut over to the kangaroo type. We need a cow probiotic. The easiest way to do this would seem to be to collect a lot of kangaroo poop and spread it on the cow hay and see what happens.
In order to conduct these vital experiments I’m planning a roo poop collecting expedition to Australia. If you’d like to contribute, and thereby save the world, please mail me a check. Or, better yet, cash.
About the Author: Steve Potter, PhD, is a Professor of Pediatrics, in the Division of Developmental Biology, at Children’s Hospital Medical Center in Cincinnati. He has authored Designer Genes: A New Era in the Evolution of Man, published by Random House 2010. In addition he has written over one hundred science papers, and co-authored the third edition of the medical school textbook, Larsen’s Human Embryology.