Flatulosaurus Heats Up the Mesozoic

A new Current Biology paper proposes that the accumulated output of dinosaur flatulence could have changed the global climate during the age of the dinosaurs. Insert dinosaur fart joke here. No, seriously, this is a real report in an actual scientific journal. It just happens to be on a subject that the news media could not resist blowing out of proportion on their best day. Given that much of the CO2 in Earth's atmosphere was emitted by some form of living creature this is a serious area for study by environmental scientists. So after giving the chattering media magpies some time to calm down, here is a more serious take on this heady topic.

Forget T-Rex, fear the Flatulosaurus—particularly if you are afraid of global warming. You may have already heard this story, scientists say that dinosaur farts had a part in warming the ancient Earth. Published online on the Cell web site, the story quickly broke in The Telegraph. A story too perfect and too funny to be ignored, the news flashed across the internet, appearing everywhere from Slash Dot to The Huffington Post.

While gushing erroneous reports that the dinosaurs farted and belched themselves into extinction, the world's entire news gathering community turned into a bunch of snickering school boys. Right-wing talk radio personality, Rush Limbaugh said it was just another attempt to bolster the argument of global warming, no matter how absurd it may seem. Some in the scientific community looked askance at the mirthful media reports. On the Smithsonian's web site, in an article entitled “Media Blows Hot Air About Dinosaur Flatulence,” the low mindedness of the news media was described this way:

In the past month we’ve had vapid reports of aquatic dinosaurs and alien dinosaurs, but at least three news sources decided to up the ante with additional bad reporting. Fox News led off with “Dinosaurs may have farted themselves to extinction, according to a new study from British scientists.” Wrong right out of the gate. Wilkinson and co-authors didn’t say a thing about dinosaur extinction in their paper. Not to mention that the idea doesn’t make any sense. Titanic sauropods were around for about 130 million years. If their gases were so deadly, why did it take so long for the world to be overwhelmed? The Fox News gloss isn’t even a misrepresentation of what the researcher said. The story’s headline and lead are outright fabrications. And the same fiction was repeated on the network’s late-night roundtable of chattering commentators, Red Eye.

Hey, I like Red Eye, and this is precisely the kind of humor that would appeal to host Greg Gutfeld. Just what did they expect? To be fair, the sophomoric guffawing was not limited to Fox: Gawker and the Daily Mail also received a fair dollop of opprobrium. No matter, there is serious science to be examined here.


Was that you, mate?.

The Smithsonian article went on to explain that, for a long time, the digestive biology of sauropods has confounded paleontologists. From their fossilized remains it is known that Sauropods had small teeth good for cropping and harvesting plants. Unfortunately, their dino dentition was not well suited for chewing or mashing up their food. How they broke down the masses of plant food they must have ingested (estimated at 520 million tons per year) remains a mystery.

Large swallowed stones called gastroliths, often found within the skeletons of herbivorous dinosaur fossils, were thought to be used to grind up the creatures food post ingestion. They would be similar to gizzard stones used by some modern birds. This would be a natural assumption since scientists think birds descended from the dinosaurs. Unfortunately, recent reviews of the evidence have failed to turn up any indication that sauropod's stones were used to grind up food.

Instead, some paleontologists have put forth the idea that sauropods were hosts to vast communities of microscopic organisms in their stomachs. In effect, the herbivorous dinosaurs were walking, microorganism-assisted fermentation vats that broke down the ingested vegetation. Such fermentation could have produced large quantities of methane, and as Wilkinson et al. point out, the end result would have been copious sauropod farts. As David M. Wilkinson, Euan G. Nisbet and Graeme D. Ruxton reported in their paper:

Mesozoic sauropods, like many modern herbivores, are likely to have hosted microbial methanogenic symbionts for the fermentative digestion of their plant food. Today methane from livestock is a significant component of the global methane budget. Sauropod methane emission would probably also have been considerable. Here, we use a simple quantitative approach to estimate the magnitude of such methane production and show that the production of the ‘greenhouse’ gas methane by sauropods could have been an important factor in warm Mesozoic climates.

The paper goes on to outline the authors' assumptions and resulting calculations. Citing recent estimates of the biomass density of herbivorous dinosaurs of 80,000–90,000 kg/km2, some 7–24 times the biomass of extant large-bodied herbivorous mammals (~28,000 kg/km2), they calculate methane emission of 2675 liters per day for one animal under the standard temperature and pressure conditions. A world full of sauropods would emit as much as 520 million metric tons, far more than the frequently maligned modern cow population.


Comparison of estimated sauropod methane emissions.

“A simple mathematical model suggests that the microbes living in sauropod dinosaurs may have produced enough methane to have an important effect on the Mesozoic climate,” said co-author David Wilkinson of Liverpool John Moore's University. “In fact, our calculations suggest these dinosaurs may have produced more methane than all the modern sources, natural and human, put together.”

This level of methane production—methane being a much more potent greenhouse gas than carbon dioxide—could have be enough to cause a 10°C rise in global temperatures during the Jurassic. “Even reducing our estimate by half still predicts a major role for sauropod methane in the Mesozoic,” the authors' conclude. In fact, they think we might take some solace from knowing we are not the only species accused of causing global warming. Contrary to what some misanthropes say about adverse human impacts on the ecosystem, humanity might find cover in this new work.

“Although dinosaurs are unique in the large body sizes they achieved, there may have been other occasions in the past where animal produced methane contributed substantially to global environmental gas composition: for example, it has been speculated that the extinction of megafauna coincident with human colonization of the Americas may be related to a reduction of atmospheric methane levels,” the paper explains. So our Paleo-Indian ancestors could claim that they were not just slaughtering native North American megafauna for food, they were fighting global warming.

Be safe, enjoy the interglacial and stay skeptical.

Flatulosaurus Heats Up the Mesozoic - just conjecture.

Yet again I see pseudoscience dressed up as fact.
We may estimate what was eaten by these historical beast millions of years ago but we have virtually no knowledge of their internal working.
What nutrients did their require?
What did they expel what was not solid?
Who can say how they digested their food?
It is not known and probably will never be known!
Do we have any facts for their basic physiology. In deed arguments still abound over very basic things like their weight and mobility, so to say we know how they digested food is more than a stretch.
No, the entire article is conjecture - and little else.

Global warming

The same happens today with the difference that today it is the cows that produce the gas.
Henrik

Don't diss the cows

I guess you didn't see the barchart in the article above, today's natural methane emissions are no where near the predicted dionsaur level. According to the EPA: "Globally, ruminant livestock produce about 80 million metric tons of methane annually, accounting for about 28% of global methane emissions from human-related activities. An adult cow may be a very small source by itself, emitting only 80-110 kgs of methane, but with about 100 million cattle in the U.S. and 1.2 billion large ruminants in the world, ruminants are one of the largest methane sources. In the U.S., cattle emit about 5.5 million metric tons of methane per year into the atmosphere, accounting for 20% of U.S. methane emissions."

Emissions of methane from natural sources are largely determined by environmental variables such as temperature and precipitation. The best available information indicates that global methane emissions from natural sources are around 208 Tg per year. However, the value is highly uncertain. (Source: from data contained in EPA Methane and Nitrous Oxide Emissions From Natural Sources, April 2010 (PDF)).

  • Wetlands. Natural wetlands are responsible for the majority of global methane emissions from natural sources, accounting for about 170 Tg of methane per year (range 105-278 Tg per year). Wetlands provide a habitat conducive to methane-producing (methanogenic) bacteria that produce methane during the decomposition of organic material. These bacteria require environments with no oxygen and abundant organic matter, both of which are present in wetland conditions.
  • Termites. Global emissions of methane due to termites are estimated to be between 2 and 22 Tg per year, making them the second largest natural source of methane emissions. Methane is produced in termites as part of their normal digestive process.There are more than 2000 different species of termites and, though the amount of methane varries, each termite produces, on average, about half a microgram of methane per day. When this is multiplied by the world population of termites, global methane emission from termites is estimated to be about 20 million tonnes each year.
  • Oceans, Rivers, and Estuaries. Oceans, rivers, and estuaries are estimated to be responsible for approximately 9 Tg of methane per year (range 2-16 Tg per year). The source of methane from oceans is not entirely clear, but two identified sources include the anaerobic digestion in marine zooplankton and fish, and also from methanogenisis in sediments and drainage areas along coastal regions.
  • Hydrates. Global emissions from methane hydrates are estimated to be around 2 to 9 Tg of methane per year. Methane hydrates are solid deposits composed of cages of water molecules that contain molecules of methane. The solids can be found deep underground in polar regions and in ocean sediments of the outer continental margin throughout the world. Methane can be released from the hydrates with changes in temperature, pressure, salt concentrations, and other factors. Overall, the amount of methane stored in these hydrates globally is estimated to be very large with the potential for large releases of methane if there are significant breakdowns in the stability of the deposits. Because of this large potential for emissions, there is much ongoing scientific research related to analyzing and predicting how changes in the ocean environment affect the stability of hydrates.
  • Geologic. Geologic emissions are estimated to be between 42 and 64 Tg of methane per year. Geologic emissions are difficult to quantify because there are many small point sources all over the Earth. One of the dominant sources of geologic methane is mud volcanoes. These structures can be up to 10 kilometers in diameter, though most are much smaller, and often form on tectonic plate boundaries or near fossil fuel deposits. Over 1,000 such structures have been located on land or in shallow water. Mud volcanoes release methane gas from within the Earth, as well as smaller amounts of carbon dioxide, nitrogen and helium. Other structures which emit methane that would qualify as geologic sources include gryphons, steam vents and bubbling pools.
  • Wildfires. Wild fires are estimated to release between 2 and 5 Tg of methane per year. Methane is released during fires due to incomplete combustion of organic material. A large fraction of these emissions come from deforestation in tropical areas, however only the emissions from natural forest fires are considered here. In addition to emissions from direct combustion, fires can lead to the release of large amounts of methane from soil, especially in high latitude regions. Here, fires melt permafrost which traps methane in the soil. In addition, warmer soil temperatures after fire events lead to greater microbial activity. Greater microbial activity increases the diffusion of methane from soils to the atmosphere.
  • Wild animals. Another highly uncertain source of methane emissions is wild animals. Bison and buffaloes are examples of animals that release methane. Estimates of how much methane is emitted from wild animals can be derived based on estimates of the population of these species. Estimates have suggested the source strength of methane emissions from wild animals could be up to 15 Tg per year.

Dinosaur Flatulence

"Titanic sauropods were around for about 130 million years. If their gases were so deadly, why did it take so long for the world to be overwhelmed?"

They hadn't started using HFC's in their food until the end of that period??

In a more serious vein, we are told that domesticated animals are fed grains and corn that are much richer than their natural diet and cause the majority of their flatulence. If that is so, why would Dinos be different and make so much methane?!?!?!

For evolutionists, why would Dinos not have evolved to more efficiently utilize their food supply after 100 million years??

Wrong type of dinosaur?

The dinosaur at the beginning of the article looks like a meat eater. I thought the dino emissions were from plant eating dinosaurs?

Dino Flatulence

That is what happens when they eat mammals!!

Sauropod spotting

Yes, yes. The lead illustration is actually a T-Rex and not a herbivorous sauropod. The original illustration, by the marvelous artist Joe Tucciarone, was in a pose that made it easy to adapt. Call it opportunistic artistic license. My modified picture is based on original artwork copyright by Joe Tucciarone and used with permission of the artist.

Dino Farts

This theory sounds like a political statement from any number of Modern Politicians ALL HOT AIR and NO SUBSTANCE.CLIMATE CHANGE is NATURAL and CO2 is LIFE.Cheers