Camels are highly evolved mammals that originated from a primitive soft-footed ungulate in North America around 55 million years ago.
Today, the dromedary camel typically inhabits hotter climates, while the Bactrian camel is commonly found in the high desert regions of Asia. Compared to the one-humped camel, the Bactrian camel is stronger, has greater endurance, can carry more cargo, and is particularly suited for long-distance travel across deserts.
With their tall stature, camels have relatively small heads, thick and long necks that are curved like a swan’s. They possess a split upper lip, which aids in foraging. Camels have long, slender legs and large hooves, allowing them to avoid the scorching desert ground.
About 10 million years ago, the ancestors of camels crossed the Bering Strait from Alaska in North America to Asia and even Africa, evolving into both the Bactrian camel and the domesticated dromedary camel.
The fur of camels is generally brown and very thick. During freezing winters, their thick fur effectively retains heat, making camels relatively cold-resistant. In the scorching summer, their thick fur not only reflects a portion of sunlight but also provides insulation, allowing camels to better withstand the heat.
Although camels are also warm-blooded animals, their body temperature can vary significantly between day and night. At night, their body temperature is around 34°C, while during the day, it can rise to as high as 41°C.
Those unfamiliar with camels may be surprised by the meaty ball that protrudes from a camel’s mouth, and many might find it unpleasant to observe. So, what is this meaty ball actually?
Although camels have relatively large tongues, the size of the tongue differs between females and males. Typically, the tongue of female camels is much smaller than that of males.
Some people think it’s a camel’s meat pouch, while others believe it’s the camel’s stomach, but both of these are incorrect. It is the tongue of the male camel during mating season.
In fact, camels, like many other animals in nature, practice a “polygynous” mating system. During the breeding season, male camels mate with multiple females, focusing on quantity rather than the quality and survival rate of the offspring.
In contrast to male camels, females are only concerned with the quality of their offspring. This is because the gestation period for female camels is as long as 13 months, and typically only one offspring is born at a time. Furthermore, female camels only conceive every two years. With such limited opportunities to give birth, it is no surprise that female camels prioritize the quality of their young, making them particularly selective in choosing mates.
Camel papillae consist of keratin, a material similar to human nails. According to Luis Padilla, director of animal health at the Saint Louis Zoo, this structure can feel like plastic. Healthy papillae protect the cheeks and mouth from scratches and injuries; if these papillae become ulcerated or dull, it may indicate that the camel is ill.
Like most female animals, female camels prioritize males with the strongest genes and the healthiest physiques as mates. So, what characteristics do male camels need to meet these criteria?
Of course, the ideal male camel is one that can produce the largest meaty ball from its mouth. As mentioned earlier, this meaty ball is actually the tongue of the male camel (it takes on a bulbous shape when the male camel inflates it).
We all know that camels are dubbed the “ships of the desert,” being the most loyal and reliable companions for humans in desert settings. Camels have the ability to withstand hunger, endure thirst, and adapt to their environment; they are simply born for desert life.
The tongue of a camel is covered by a thick layer of “calluses,” effectively preventing injuries from thorns.
The upper and lower jaws of camels are also covered with spines, which can break the thorns of plants like cacti. Their salivary glands are highly developed, producing a viscous saliva that can counteract the thorns of desert vegetation.
With such a pair of “iron jaws and steel tongues,” male camels fearlessly face the harsh desert environment. In the eyes of female camels, a male that can expel a larger meaty ball signifies a stronger chance of survival and superior genes compared to other males.
In addition to their ability to chew cacti, the hump of camels can store a large amount of fat, which can be converted into energy to sustain bodily functions when food is scarce. Furthermore, camels can also reduce their metabolic rate during times of food scarcity.
The tongue of a camel is also covered with spines, which have very few pain receptors, thus preventing pain sensation.
The nasal cavity of camels is very large, containing numerous thin and curved tubes. When the camel’s body experiences severe dehydration, these tubes stop secreting fluids, forming a hard layer on the surface of the tubes. Using these layers, camels can absorb water through respiration without losing moisture from their bodies. In this way, camels minimize their own water loss.
The stomach of a camel is filled with bubbles that help it store a significant amount of water. An adult camel can store tens of liters of water in a single drink.
From this perspective, the evolutionary level of camels can even be compared to that of humans.
