There is no denying that zebras are one of the most bizarre and startling species of horses! But many questions revolve around these animals:
The first question: Is the zebra white with black stripes, or vice versa?
What is the importance of having this strange color pattern on their bodies?
It seems that the researchers have already confirmed their theory about these questions and reached the logical answers!
What color is the original zebra skin color?
In the Middle Ages, people believed that zebras had white bodies with black stripes. Evidence for this hypothesis lies in the fact that they have a white lower abdomen. That's logical. White, being a lighter color, will be the basis for dark black.
However, recent studies have proven otherwise. Zebras are black in color with white stripes!
The skin cells of most animals - including zebras and humans - produce a pigment called melanin. This gives humans our skin tone and hair color, and zebras their black color. However, in the case of a zebra, instead of being all black, some skin cells are asked not to produce melanin; Those are the white lines that we see.
Additionally, imaging of zebra fetuses has revealed that they are completely black. The white streaks appear during the last embryonic stage.
How were the white lines patterns formed on the bodies of zebras?
Lines are mainly formed due to selective pigmentation. As mentioned, zebra embryos are completely black, while white stripes appear in the last embryonic stage. Melanoma skin cells produce the pigments that give color to fur.
Some chemical correspondence identifies the melanocytes that transport melanin to specific filaments; Those that do not receive melanin appear black, while those that do not receive melanin appear white.
Pigmentation is controlled by activating or inhibiting specific genes. In the case of zebras, those areas with white stripes are where the pigmentation gene has been inhibited. Black is the actual color of fur, and white spots are simply areas where pigmentation is not present. The fact that the skin under the zebra's fur is black supports this conclusion.
This pattern of pigmentation is known as “selective pigmentation.” These differences in the stripe patterns are related to how cells differentiate, a process by which stem cells transform into other cells with a specific function (such as liver cells or skin cells) as the embryos develop.
During this development, a type of cell called neural crest cells moves around the developing embryo and forms different types of cells such as brain cells, bone, muscle, skin, or melanocytes. As these neuronal apex cells differentiate into melanocytes, many genes are turned on or off.
Depending on when these genes are turned on, the streak patterns form accordingly. Research has shown that the earlier melanocytes mature, the thicker the zebra stripes.
What is the purpose of zebra stripes?
This question does not have a single straight answer. There are several hypotheses:
Camouflage
Zebra stripes serve as camouflage to deter their primary predators: lions and hyenas. Because animals huddle together, experts believe the block of lines can confuse predators by acting as an optical illusion, effectively blending their shapes together. Therefore, a herd of zebras can create the optical illusion of a gigantic mass, thus deterring any predator.
Regulatin
ody temperature
Zebras spend a lot of time grazing on open plains, which means they must withstand the intense African heat for long periods. Zebras with more prominent stripes generally live in the northern equatorial region of their range, while those with less prominent stripes are found more commonly in the cooler southern regions of the range. This geographic distribution supports the utility of lines as thermoregulators.
Resistant to flies and pests
The tsetse fly is a major problem for animals in tropical Africa. These parasitic flies cause trypanosomiasis disease in both animals and humans. One hypothesis supported by some evidence is that zebra stripes confuse flies. A study published in 2014 in the journal Nature found that flies, which you might imagine being a common pest of zebra, are less likely to sit on black and white striped surfaces.
In 2019, Japanese researchers painted cows black and white and found that fly bites were reduced by 50%. They have proposed this method as a possible preventive method for the spread of disease through tsetse flies.
Here's the bottom line ... according to the principles of embryology, the original color of zebras is black. The white color is actually the stripes that surround the main black background of their bodies. There has always been a popular belief that the zebra is a white animal with black stripes, but scientifically, it turns out that the opposite is true.
Commentaires