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Panda's lazy lifestyle explained
#1
Why are pandas so chilled? The clue is in the bamboo 

Hoops and hurdles
There are few animals on the planet as iconic as the giant panda. Its role as the logo for the World Wide Fund for nature, the perilous nature of its existence in the wild and the fact that it has been exported worldwide as a symbol of Chinese political friendship for decades, continue to sustain its status.
Despite this phenomenal popularity, its political importance and threatened conservation status make it extremely difficult to do research on pandas. There are many, and justified, hurdles to jump to do scientific work on animals in general, but they are even higher when it comes to pandas. 
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For this reason, there are many fundamental measurements that have been made on other species but that are lacking for pandas. However, we are slowly starting to fill in these gaps.


Gut of a lion …
One bit of biology that many of us are familiar with is that the panda is a carnivore that became a vegetarian. The mammalian order Carnivora includes several families of animals including the canids (wolves, dogs and foxes), felids (cats), mustelids (weasels and so on), pinnipeds (seals, walruses and sea-lions) and ursids (bears). All these groups apart from the bears subsist by killing and eating other animals.
Because meat is easily digested these animals have short digestive tracts. Apart from the polar bear, many bears include various amounts of vegetable material into their diets. The panda has taken this to the extreme: eating almost exclusively bamboo.
Although pandas have many adaptations for eating bamboo (like an extra “thumb” to help hold the shoots) these do not include a long digestive tract. The panda also has the guts of a lion: ideal for digesting meat, but very inefficient for digesting bamboo. So they have to eat lots of it, perhaps as much as 10-20kgs per day. Scientists have long speculated that to survive on such a low-quality food pandas must have a low rate of metabolism.
However, until now nobody had managed to measure exactly how much energy they use. To do this, we used a technique called the doubly-labelled water method, which measures the rate at which animals eliminate stable isotopes from their bodies. We did this for five captive pandas at Beijing zoo and three wild pandas living in the Foping nature reserve.
We found that the pandas’ metabolic rate is exceptionally low. Corrected for their body weight of about 92kg (203lbs), it is substantially lower than almost all other mammals. In fact, the rate is closer to what would be predicted for a 90kg reptile.

… mobility of a sloth?
How they achieve such low rates of energy use was the focus of the second part of our paper, published in the journal Science. Much of the energy that our bodies use is burned up in relatively few organs, including the brains, kidneys, heart and liver. Using historical autopsy data we found that pandas have small organs for their body size.
Their brains are only 82% of the expected size, their kidneys only 74.5% and their livers a remarkable 62.8% of the expected size for a 90kg mammal. Plus if you ever went to see a panda in a zoo you will know that they are not the most active of animals. Indeed using GPS loggers we found that in the wild pandas move on average at just 26.9 metres per hour.
A key physiological system involved in regulating our metabolism is the thyroid hormone system. We suspected that pandas might have something unusual going on with their thyroid hormones – a hunch that turned out to be correct.
Pandas have very low levels of the main thyroid hormones T4 and T3. We were able to trace these low hormone levels to a unique mutation in the panda genome, which affects a critical gene involved in thyroid hormone synthesis. People who have low thyroid hormone levels often complain that they feel cold. This is potentially because their lowered metabolic rate is insufficient to keep them warm.
[Image: image-20150708-31563-ll6zjq.jpeg?ixlib=r...4&fit=clip] I’m cool and I know it. Yonggang Nie, Author provided
So how does the panda manage to keep warm? Despite living in semitropical habitats, it does have a really thick fur coat. This serves to trap what little heat their metabolism produces inside their bodies. A direct consequence of this is that their surface temperature (measured using a thermal imaging camera) is about 10°C cooler than the surface of other black and white animals like the zebra. Pandas, it seems, are literally cool.


Source: https://theconversation.com/why-are-pand...mboo-44435

Ursus21 Wrote:Giant Pandas' Lazy Lifestyle Justified by Science

Giant pandas have an insatiable hankering for bamboo, but scientists have long wondered how the bears survive on such a fibrous and low-nutrient plant. Now, a new study finds that giant pandas have clever ways to conserve energy, including having lazy lifestyles, small organs and special genes.

The researchers followed five captive and three wild giant pandas (Ailuropoda melanoleuca) for about a year. By using GPS trackers and analyzing chemicals excreted in the pandas' poop, they were able to measure the amount of energy the pandas spent each day. Surprisingly, the pandas expended only about 38 percent of the energy that an animal with the same body mass would require.

"We thought the metabolism of the panda would be low because the bamboo diet contains low energy," said senior author Fuwen Wei, a professor of zoology at the Chinese Academy of Sciences in Beijing. "But it is very surprising that it is this exceptionally low, equal to the three-toed sloth, and much lower than the koala."

The only known mammals that have a lower daily energy usage than the giant panda are the Australian rock rat (Zyzomys argurus), which spends 21 percent of its expected energy per day, and the golden mole (Eremitalpa namibensis), which spends 26 percent of its expected energy per day, the researchers wrote in the study. However, while it's unknown how the rock rat and golden mole conserve energy, the researchers found several ways that pandas save calories.

For starters, the GPS recordings showed that pandas are a lazy bunch; they don't move a lot, and when they do, they move slowly. Captive pandas spent just a third of their time, and wild pandas about half of their time, moving around, the researchers found. Furthermore, wild pandas forage at an average speed of 50 feet (15.5 meters) an hour, a rate that is "very low," the researchers wrote in the study.

The researchers also reviewed giant panda autopsy data, and found that relative to their size, the animals have a smaller brain, liver and kidneys than other bears. These small organs likely require less energy to function, saving the pandas precious calories, the researchers said.

Finally, the research team looked at the giant panda's thyroid hormones, which regulate metabolism. A hormone sample taken from the captive pandas showed that levels of two thyroid hormones — thyroxine and triiodothyronine — were about half of what is seen in mammals with the same body mass, the researchers found.

In fact, these hormone levels were even lower than those seen in hibernating black bears (Ursus americanus), they said. Interestingly, giant pandas have thyroid hormone levels comparable to the gray seal (Halichoerus grypus), which lowers its metabolism while diving to conserve energy, the researchers said.

Source: Giant Pandas' Lazy Lifestyle Justified by Science
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#2
Damn pandas not.looking for work and living off welfare. Anyway, that was a pretty intresting article Caninecanis. I have no idea why it just occurred to me that Pandas are carnivores gone vegan...kinda amazing to be honest.
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