China’s Giant Pandas are known for being fussy eaters. Pretty much the only thing they snack on is bamboo. And “snack on” is putting it lightly. Many experts have said that Giant Pandas appear to be spending so much eating bamboo (they can consume up to 83 pounds per day), only so they can gather the energy to keep eating. But a new study has found an explanation.
The study, published earlier this week, on Friday (July 10, 2015), in the journal Science, has revealed that the Giant Panda’s lazy attitude and lifestyle are a direct consequence of their dietary choices.
It turns out that the adorable animals don’t get the energy that they need from bamboo, which causes their metabolic rates to be low, and in order to manage the situation they end up using a lot less energy that an animal their size should.
The Giant Panda was a carnivorous creature millions of years ago, and researchers believe that their gut microbes have still not adapted to the change in diet. On top of everything, their digestive system isn’t well designed to break down plants either.
For their study, a group of researchers from China and Scotland have teamed up to measure how much energy is being expanded by Giant Pandas. They monitored five (5) captive pandas, and three (3) wild pandas, and injected them with a shot of “doubly labeled water”, a formula enriched with hydrogen, oxygen and certain isotopes. They then spent the next two (2) weeks taking blood samples from the animals so that they could determine the rate at which the animals’ bodies eliminated the doubly labeled water.
What they found was that the captive bears only used roughly 38 percent (38%) of the energy an animal their size should, while the wild bears used roughly 45 percent (45%) of the energy an animal their size should. On average, the pandas 4.6 megajoules of energy each day, which translates to burning roughly 1,100 kilocalories. The researchers said this was very low, as the average Giant Panda weights somewhere around 200 pounds.
The researchers also mentioned that the pandas didn’t move all that much. On average, wild pandas were physically active 49 percent (49%) of the time, and when they did move, their speeds were slow. The captive pandas moved even less, an average of 33 percent (33%).
Because bamboo is high in fiber and low on calories, the Giant Pandas have to eat up to 83 pounds of it each day in order to muster up enough energy to get through their day. Another study published a few months ago, in May, has found that the creatures only digest roughly 17 percent (17%) of the bamboo that they consume throughout the day.
The research team wrote a statement saying that “Giant pandas have exceptionally low [daily energy expenditure], which may facilitate survival on their diet of bamboo”.
An additional explanation is that Giant Pandas have under-active thyroid glands and much smaller livers, kidneys and brains than other massive mammals, and thus require less energy. Sci-News informs that the animal’s thyroid hormone levels are just a fraction of what they should be.
It’s worth noting that the Giant Panda’s low metabolic rate is not an indication that the animal is constantly cold. Its thick fur serves to maintain high body temperature.
Image Source: nouahsark.com