Although often confused, camels and dromedaries have clear distinctions that can be observed through the number of humps, physical build, and coat type. Furthermore, they inhabit distinct ecosystems.
Both are classified as camels because they belong to the same genus, Camelus. However, in popular Portuguese vocabulary, the term 'camel' refers to the two-humped species, also known as the Bactrian camel. These animals are part of the camelid family, which originated in North America approximately 40 million years ago. The ancestors of the genus Camelus only migrated to Eurasia about 6 to 7 million years ago, using the ancient land bridge of the Bering Strait.
The camel, specifically *Camelus bactrianus*, is characterized by having two humps and inhabiting exclusively Central and Eastern Asia, including nations such as Mongolia, China, and Kazakhstan. Its robust and heavy body is covered with thick and long fur on the neck, top of the head, humps, and upper parts of the front legs. This fur functions as an essential adaptation to extreme climate deserts, such as the Gobi, where temperatures vary drastically, from -40 °C to over 40 °C. During spring, these camels shed their coat. They are considered excellent pack animals, capable of advancing about 5 km/h in a caravan and covering between 30 and 50 kilometers daily.
There is also a variation of this camel, the wild Bactrian camel (*Camelus ferus*), which survives only in regions of the Gobi and is under severe risk of extinction.
In contrast, the dromedary (*Camelus dromedarius*), also called the Arabian camel, has only one hump. Its geographical distribution covers North Africa, the Sahel, the Horn of Africa, the Middle East, and certain areas of South Asia, such as India and Pakistan. Additionally, there is a considerable population in Australia, descended from animals introduced to the country during the 19th century.
Due to its longer legs and leaner body, the dromedary demonstrates greater speed compared to the Bactrian camel. Trained animals can maintain a pace of 16 km/h for up to 18 hours, making them suitable for fast travel.
Both camels and dromedaries play a fundamental role in desert environments. They are used as means of transport and provide valuable products such as milk, meat, leather, and wool. One of their most notable capabilities is the ability to survive long periods without ingesting water. In hot conditions, they can endure up to about two weeks without drinking, while in winter, when there is moist vegetation, they can go months without water.
When finding water sources, they can consume more than 100 liters in a short period. It is important to note that the humps do not store water, but rather fat, which serves as an energy reserve. Resistance to dehydration is sustained by other physiological processes, such as highly efficient kidneys in concentrating urine, the production of very dry feces, a body temperature variation of up to 6 °C throughout the day, which minimizes sweating, and tolerance to losing up to 30% of body weight relative to water.
Genetically, camels and dromedaries are very close and can reproduce with each other. First-generation hybrids are fertile and generally exhibit greater size and strength than their parents; however, subsequent crosses between these hybrids tend to result in less vigorous individuals.
These two types are the best known within the camelid family, which also includes South American relatives, such as the llama, alpaca, guanaco, and vicuña.