Loopy, the new "top streamer" of emojis, still has to act according to the mood of the river in real life...

Recently, Loopy from the Korean animation "Pororo" has become a hot topic on the Internet. Her cute appearance coupled with her frustrated, distorted or weird expressions has struck a chord with many netizens, and she has quickly become their "spiritual substitute" and spread on the Internet.

Loopy emoticon package pictures are collected from the Internet

In the animation, Loopy's prototype is a shy beaver that lives in a hollowed-out tree trunk. In the real world, beavers also like wood materials. They use their sharp teeth to bite off trees and other vegetation. In addition to eating them, they also use them to build dams and homes. Their construction ability is at the ceiling level among mammals , and they are also known as "natural dam engineers."

Image source: Istock/Dan Pepper

Beaver family belongs to the Beaver suborder under the Rodentia order. Today, there is only one genus Beaver left under the Beaver family, which includes two species: the Eurasian beaver and the American beaver .

The American beaver on the left and the Eurasian beaver on the right. Image credit: Gilles Delhaye

In 1758, the taxonomist Carl Linnaeus coined the scientific name castor for beavers and the specific name C. fiber for the Eurasian beaver. The specific name C. canadensis for the American beaver was coined by German zoologist Heinrich Kuhl in 1820.

Although they are called different names, for a long time scientists were unclear whether the two were independent species or subspecies. It was not until chromosome examination that they discovered that the Eurasian beaver has 48 chromosomes, while the American beaver has only 40. The chromosomal differences prevented the two species from getting together.

Further geographical clues also reveal the relationship between the Eurasian beaver and the American beaver. About 8 million years ago, a group of beavers originally living in Eurasia migrated from the Bering Strait to America and settled on this continent. Since then, the beaver families in Eurasia and America have parted ways.

Eat some "tree" bars. Image source: california

Compared to the American beaver, the Eurasian beaver has a longer skull, a more pronounced triangular opening in the nasal bone, lighter fur, and a shorter body.

Eurasian beaver Image source: Hangsna

Among existing rodents, besides the capybara we wrote about before , the second largest is the beaver. Their body length is between 110cm-170cm (including the tail), they can reach a height of 60cm, and weigh 11~30kg. They look like an enlarged version of a "rat", but like the capybara, this "big rat" looks... weirdly cute.

One of the most notable features of beavers is their four large incisors , which are made more resistant to acid erosion and hard enough to chew through trees because of the iron compounds in their tooth enamel.

Beaver's incisors. This bright orange-red color is given by the element iron. Image credit: Megan Fellman

It is used like a carpenter's chisel, which can cut a thick tree into small thin poles bit by bit, and finally borrow a little force from the wind, and the big tree will fall to the ground with a loud bang.

The tree fell down due to the cooperation of beavers and wind. Image source: BBC

As a semi-aquatic creature, beavers are a bit clumsy on land, but they can fly very fast in water. There are webbed fingers between the beaver's hind paws, and they can propel themselves by crossing their hind limbs. When swimming underwater, they can reach speeds of 8km/h and can easily escape the pursuit of natural enemies such as bears and wolves.

"Swimming Athlete" Beaver Photo Source BBC

In order to live more safely and comfortably in the water, beavers have also mastered the art of building dams to protect themselves from natural enemies.

Every beaver that is about to become an adult faces a huge challenge: building a home of its own. For a novice beaver that has just left its family and has insufficient experience in the wild, this nest is not only related to its own survival, but also a powerful bargaining chip to attract future mates.

To build a home, you must build a "dam", which has been the unchanged ancestral precept of the beaver family for thousands of years. In the selection of the site of the dam, beavers generally have two requirements. First, there must be water, which is convenient for beavers to quickly escape to the water when they encounter danger. Second, there must be forests to provide them with food and building materials.

A beaver standing in the water to eat feels very safe. Image source: BBC

Generally speaking, river banks are the most common settlements for beavers (as the name suggests), because there are usually abundant aquatic plants and trees growing on both sides of the rivers.

When building a dam on a river, it is important to follow the will of nature. If the river water rises sharply and the current is rapid, it means that the river is in its flood season. The water contains turbulent energy, which can easily destroy the dam under construction.

Dam destroyed by floods (Source: BBC)

Therefore, beavers will also identify the "mood" of the river before construction, and choose to start construction when the river is not so turbulent. First, beavers will bite off large trees as the base, and then bite off smaller branches with their teeth and drag them to the base. As branches are stacked together, the prototype of the dam begins to emerge.

Dam built with branches Image source: BBC

The next step is to reinforce the dam. At this time, their flexible forelimbs play an important role. The beaver's forelimbs can carry stones from the riverbed and press them on branches, and can also bring soil to reinforce the gaps. After several days of work, the dam is finally built.

Moving stones to strengthen the dam. Image source: see watermark

The built dam can slow down the flow of the river, thereby collecting more water and turning it into a small pond. The beaver's home is built in the small pond or on the bank, made of a mixture of branches, grass, mud and moss. The several holes leading to the hut are hidden in the water. Since the water in the pond is deep enough, it can avoid the pursuit of land predators.

Beaver House Image Source Slice

At the same time, as the river overflows the river channel and covers the woods on the shore, beavers can get closer to their food sources more safely. In addition, under the pond, beavers have also established a well-developed canal network connecting dams, homes and food storage rooms, which helps them transport food or materials to the corresponding places.

Underwater channel image source BBC

The dams built by beavers are not only beneficial to themselves, but the wetlands evolved from small ponds are also good habitats for some birds and mammals. However, this behavior (biting trees and building dams) has interfered with people's use of land in some areas.

Image source: BBC

Historically, the number of beavers in North America once reached 60 million, but by the 1980s, the number had dropped sharply to 10 million. In addition to being hunted by humans due to "illegally built" dams, beavers' fur and glands also have high economic value, so they are also hunted by local residents and fur hunters.

Fortunately, with the rise of environmental protection concepts, the demand for beaver products has gradually disappeared, and large-scale beaver hunting no longer exists. Today in the Americas, beavers are continuing to build their homes.

References:

1.Horn S, Durka W, Wolf R, Ermala A, Stubbe A, et al. (2011) Mitochondrial Genomes Reveal Slow Rates of Molecular Evolution and the Timing of Speciation in Beavers (Castor), One of the Largest Rodent Species. PLOS ONE 6(1): e14622. https://doi.org/10.1371/journal.pone.0014622

2.Lyle M. Gordon et al.,Amorphous intergranular phases control the properties of rodent tooth enamel.Science347,746-750(2015).DOI:10.1126/science.1258950

Editor: Guru