Wearing a helmet for ice and snow sports, a multicolored "ice ribbon" surrounds his face, and wears a freely transforming "ice crystal suit", the overall image resembles an astronaut. This is the mascot of the new "top stream" and the worldwide winter Olympics mascot - "ice pier". Its prototype is the giant panda.
As one of the most adorable animals in the world, the giant panda is a rare animal unique to the mainland, with round cheeks, large dark circles, a chubby body, and an iconic inner figure eight walking style.
Image source: pixabay
The giant panda belongs to the carnivorous order, is the only mammal in the genus of giant pandas, and although it retains the typical carnivorous digestive method, it eats almost only bamboo in its daily diet.
So, can giant pandas eat meat? The answer, of course, is yes. And it can break down and digest meat food very thoroughly. It's just that the giant pandas are no longer interested in meat and have begun to "picky eaters".
The reason is that according to the researchers, the giant panda's umami receptor gene TAS1R1 lost its normal function, resulting in the giant panda not being able to perceive the umami taste in the meat food. Therefore, when the meat food enters the mouth of the giant panda, it will feel "taste the same as chewing wax".
At the same time, the researchers also found that the time in giant pandas that the gene lost function coincided with the time when the giant pandas changed from meat to plant food. It is speculated that the loss of this gene function may be one of the driving forces behind the dietary changes in giant pandas.
In addition, there are also some genetic changes that are also beneficial to the survival of giant pandas, on the one hand, to help giant pandas improve the efficiency of vitamin A utilization, to meet the needs of maintaining the dark vision of giant pandas, on the other hand, it can alleviate the physiological impact of vitamin B12 deficiency.
Interestingly, the researchers also found that the above genetic changes also occurred in red pandas. Due to the long-term adaptation of these two animals to similar living environments, similar changes in genes have evolved into similar morphological characteristics or structures, showing us the most amazing evolutionary phenomenon in nature - convergent evolution.
How exactly do pandas make full use of the limited nutrients in bamboo? By comparing the genomes of giant pandas, polar bears, ferrets, dogs, tigers, people, and mice, the researchers found that the genes involved in limb development produced changes, which synergistically promoted the development of the panda's pseudo-thumb, and observed that there was a relative uniqueness in the changes in such genes. At the same time, the three genes involved in protein digestion have also changed, which can help giant pandas improve the efficiency of lysine and arginine release in dietary proteins, and promote the circulation of amino acids, so as to make full use of the limited nutrients in bamboo.
Source: Popular Science Times
Author: Liu Yunfeng, 2021 master's student, School of Basic Medical Sciences, Dalian Medical University; Supervisor: Professor Sui Hongjin, Department of Anatomy, Dalian Medical University
Editor: Mao Mengyuan
Review: Wang Fei
Final Judge: Chen Lei