What adaptation keeps hippos from getting sunburned?
The Correct Answer and Explanation is:
Correct Answer:
Hippos secrete a natural oily substance from their skin, often called “blood sweat,” which acts as a sunscreen to protect them from sunburn.
Explanation
Hippopotamuses are large semi-aquatic mammals that spend a significant portion of their time submerged in water. This behavior helps regulate their body temperature and protects their skin from the harsh effects of the sun. However, when exposed to sunlight, especially during basking periods, their skin becomes vulnerable to sunburn and dehydration. To address this challenge, hippos have developed a unique and effective adaptation: the secretion of a natural oily substance from specialized glands in their skin.
This secretion, commonly referred to as “blood sweat” due to its reddish or pinkish color, is neither blood nor sweat. It is a type of mucous fluid that acts as a natural sunscreen. The secretion contains two main pigments: one red (hipposudoric acid) and one orange (norhipposudoric acid). These pigments absorb ultraviolet rays and provide a protective layer over the skin, reducing the risk of sunburn. Additionally, this fluid has antibacterial properties, which also help in preventing infections, especially when hippos get wounded.
The secretion begins to ooze from the skin soon after birth, indicating its vital protective function throughout the animal’s life. When the oily layer is exposed to air and sunlight, it darkens, forming a visible coating over the body. This adaptation is particularly important because the hippo’s skin is very sensitive and can dry out or crack easily when left unprotected under direct sunlight.
This dual-purpose fluid not only prevents damage from UV radiation but also helps in keeping the skin moist and protected from harmful microbes. Through this natural adaptation, hippos manage to thrive in their hot, sunny environments without suffering the harmful effects of prolonged sun exposure.
