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Elephants stand as magnificent creatures, holding the title of the largest terrestrial beings.
Elephants, being colossal creatures weighing up to 7 tons and herbivores, spend a remarkable 16 hours a day feeding. They consume about 150 kg of grass, small branches, leaves, fruits, and gulp down 160 to 300 liters of water every day to sustain their immense energy needs.
Elephants claim the title of the largest land mammals. African savanna elephants are the largest among them, with adult males reaching shoulder heights of 304–336 cm and weighing between 5.2–6.9 tons, while females stand at 247–273 cm and weigh 2.6–3.5 tons.
Why is it said that elephants have no natural enemies in the wild? On one hand, even a newborn elephant can be perceived as a colossal marvel. With a pregnancy lasting 22 months, double that of humans, a newborn elephant weighs about 120 kg, rivaling or surpassing the size of many carnivorous species in the wild.
On the other hand, elephants are highly social animals with strong family bonds and remarkable intelligence. Newborn elephants are fiercely protected by their parents and siblings. Whether foraging, drinking, or resting, the herd ensures the safety and central position of the young elephants.
Recent independent studies reveal that the elephant's genome harbors numerous copies of genes encoding cancer-resistant proteins, surpassing the human genome. Consequently, the incidence of cancer in elephants remains consistently below 4.8%, in stark contrast to humans where it ranges between 11% to 25%.
Over the span of millions of years since elephants first appeared, they have never truly faced natural predators (with humans being their only natural threat).
Through extensive research, scientists have uncovered a fascinating trait in elephants that might spark envy in humans - elephants are virtually cancer-free!
In the 1970s, Richard Peto, a scientist from the University of Oxford, United Kingdom, pointed out that, theoretically, the larger and longer-lived an animal is, the more cell divisions it undergoes, increasing the risk of cancer. However, in reality, cancer rates seem unrelated to the lifespan and body size of animals.
Subsequently, scientists identified a gene named P53 present in both human and animal bodies. This gene can repair DNA mutations and inhibit cancer, earning it the nickname 'tumor suppressor gene.'
Elephants, mammals belonging to the Elephantidae family, hold the title of the largest land animals today. Currently recognized as three species: the African bush elephant, the African forest elephant, and the Asian elephant.
In the human body, there's only one copy of the P53 gene. When it malfunctions, humans are susceptible to cancer. Interestingly, elephants have 20 copies of the P53 gene, and even if some are faulty, others can still function normally. Theoretically, elephants have a low risk of developing cancer, and there's no recorded instance of an elephant dying from cancer.
With no natural predators and a resistance to cancer, elephants have an impressive average lifespan, comparable to modern humans. In the wild, elephants live on average from 60 to 80 years. In captivity, they can live up to 100 years.
It's peculiar that elephants, with their long lifespan, have never been observed to die of natural old age.
Elephants typically have 26 teeth: tusks, 12 front milk teeth, and 12 molars.
The mystery lies in the intricate dental structure of elephants. When we refer to their 'teeth,' it's not just the long tusks but the molars inside their mouths.
Similar to humans, elephants undergo the process of shedding their milk teeth and growing new ones. When born, elephants have four molars and milk teeth. Around the age of two, these four molars and milk teeth fall out, and new molars emerge.
Unlike humans, an elephant's molars change every few years. Throughout an elephant's life, it will go through a total of six molar changes. The sixth set of molars grows in around the ages of 30 to 40, accompanying the elephant into the latter half of its life.
In contrast to most mammals, which grow milk teeth and replace them with a single permanent set, elephants are multi-set tooth animals, constantly replacing teeth throughout their lives. The molars are replaced six times in a typical elephant's lifetime.
The first five sets of molars in an elephant all have round and flat tips, but the sixth set has pointed tips. After growing the sixth set of molars, if an elephant chews on hard foods like tree bark, nuts, or thorns, the molars will wear down quickly.
Once the sixth set of molars is worn out, the elephant can no longer chew food, leading to starvation. In the wild, despite their theoretically long lifespan, elephants never die of old age. Instead, they often succumb to starvation due to their inability to chew food.
Additionally, elephants possess a unique ability—they can predict impending death. When sensing that their time is near, they quietly leave the herd and go to a secluded place, awaiting the inevitable toll of the death knell. After the elephant dies, it becomes a feast for carnivores like wild dogs, wolves, lions, tigers, hyenas, and jackals until only the bones remain. This, perhaps, is nature's cycle of rebirth.
Source: Zhihu, a wellspring of knowledge
