What role does 'wrinkle' on the skin of African elephant play?

by Magda Ehlers

African elephant wrinkles are like a crack in a dry ground and stand out, but for a long time no one researcher unravels the mystery of "Why is African elephant's body deep wrinkles?" . However, the paper published by the research team of the University of Geneva and the Swiss Biotechnology Informatics Institute reports that it is clear what role African elephant wrinkles play.

Locally-curved geometry generation bending cracks in the African elephant skin | Nature Communications
https://www.nature.com/articles/s41467-018-06257-3*

Why Do Elephants Have Wrinkled Skin? New Study on Cracks Solves Old Mystery | Inverse
https://www.inverse.com/article/49479-why-do-elephants-have-wrinkled-cracked-skin

Michael Millikovic 's laboratory at the University of Geneva, who led the research, is studying the developmental and evolutionary mechanisms of diverse life on the planet. Among them, Mr. Millikovic is interested in the process of forming the form of the living things, and in 2013 "The skin of the crocodile's face is formed by a process similar to cracking of the chilled porcelain "We announced the result of the study. Since then, Mr. Mirnkovic decided to study the process of skin formation of other organisms, and he began research on the process of forming deep wrinkles on the skin of African elephant.

The researchers used microscopic observation and computer modeling to analyze the functions of African elephant wrinkles. Mr. Milnikovic says, "Although it is skin of African elephant that seems to be only cluttered wrinkle at first glance, if it is examined carefully, each crack is connected by very fine wrinkle and forms a complicated network I understand. "

by Pixabay

The wrinkles of African elephants are connected by a network of micro cracks, and as rain falls, water touches the skin and at the same time it plays a role of spreading water throughout the skin like a canal. "This beautiful wrinkle pattern prevents moist dirt from falling off the skin and can diffuse and hold 5 to 10 times more moisture throughout the skin than smooth skin," Milnikovic said , African elephant wrinkles are helping to control body temperature efficiently by heat of vaporization.

In the dry African land, you need to take full advantage of a small amount of moisture from rain that sometimes goes down. Therefore, African elephants are taking a mud not only playing, but also have the meaning of allowing moisture to spread to the skin to protect themselves from the harsh environment. It paints mud on the skin, keeps moisture, and at the same time it protects you from the harsh sun and parasites.

by Pixabay

Even with the same elephant, the skin of Asian elephant is not engraved with deeper wrinkles than the skin of African elephant, and if you know even the features you can easily distinguish them. The research team examined samples of skin provided by scientists and museums to find that it is the outermost stratum corneum of the skin that forms wrinkles in African elephants.

When the research team examined the process of skin formation, it turned out that African elephant wrinkles are not carved not by contracting the skin, but by curling by extending the skin beyond the surface area. According to computer model analysis, the research team found that a young African elephant is subjected to a force to bend the surface of the skin as it grows and a deep crack is carved. African elephant wrinkles are extremely hard and keratinised and are rich in keratin like human nails and hair.

This discovery also revealed the mystery "why there is no deep wrinkle in the newborn African elephant baby?" The skin of the baby elephant is still soft and dead wrinkle is carved so that it is not keratinizing. The surface of the African elephant's skin will become harder as it grows and the wrinkles necessary to survive savanna will increase.

Milkhkovic says that there are deep wrinkles only in African elephants and that the reason why Asian elephant has no wrinkles can be explained by the inhabiting environment. Asia elephant lives in a humid climate area, so you can get enough water without wrinkles. On the other hand, skin wrinkles are very useful for African elephants who need to efficiently dissipate heat from the body in a situation with low moisture and deal with the heat.

by Harvey Sapir

In addition, Mr. Mirnkovic found that there is similarity to the wrinkled skin of African elephant and human skin having genetic disorder called vulgaris ichthyosis . Even in the case of vulgaris ichthyosis, hard and thick skin is formed like African elephant, but in the case of African elephant it is not necessary for human being even though it is the trait necessary for survival.

Mr. Milnikovic said, "Despite similar phenomena occurring in the skin of African elephants and humans, it is not beneficial in the former and in the latter evolved as an adaptation necessary for survival." I think that it can be an attractive research subject. "The example of wrinkles in African elephants is a very beautiful example that the form of animals was caused by a physical process," he said.