Elephants actually suffer from cancer more often than previously thought, but they possess a unique secret that helps them cope.

Theoretically, large animals should get cancer more frequently than smaller ones, and for decades, biologists struggled to understand why this is not the case. Many researchers hoped that a solution for treating cancer in humans could be found in the elephant genome, but a new study claims that this line of research is actually diverting scientists from making discoveries, as reported by IFLScience.

In the new study, researchers found that large animals, particularly elephants, are indeed quite prone to cancer. Essentially, the larger the animal, the more cells it has in its body, and consequently, the more times these cells will divide. A longer lifespan also necessitates more cell divisions, and while an animal’s size does not always predict its lifespan, these two factors generally go hand in hand.

It is known that each cell division carries the risk of something going wrong, resulting in a mutation. Most mutations do not lead to cancer, but there are enough that increased cell division becomes a cancer risk. An observation made nearly 50 years ago that this does not happen was termed Peto's paradox, named after Sir Richard Peto, who first reported it.

The common belief that cancer is rare or absent in species such as elephants and sharks gives scientists hope for discovering effective treatments for humans. However, a team of researchers led by Professor Chris Venditti from the University of Reading concluded that these claims are incorrect.

During the study, the scientists compared cancer incidence rates across 263 species, including large species like elephants and giraffes, as well as some large reptiles. A similar study was conducted last year, but it yielded ambiguous results. On one hand, that work concluded that cancer incidence rates are higher among large animals, contradicting the paradox; on the other hand, this correlation was weak. Researchers also found that longer gestation periods are likely linked to lower cancer incidence rates.

According to Professor Venditti, he and his colleagues utilized data collected for the study and conducted their own analysis. The results indicate that larger animals, such as elephants, actually face higher cancer incidence rates. In the study, researchers examined the differences between birds and mammals and found that in both groups, larger species exhibit higher cancer incidence rates.

Nevertheless, scientists do not entirely dismiss the idea that elephants possess some form of immunity. Research shows that these animals indeed have a higher cancer incidence rate than mice, but they also resemble animals that weigh about ten times less—such as tigers. In simple terms, elephants likely have a few tricks up their sleeves.

According to co-author of the study, Dr. Joanna Baker, when species needed to grow larger, they seemingly also developed remarkable defenses against cancer. Researchers assert that elephants have developed complex biological tools to "keep cancer in check." Essentially, this adaptation is a prime example of how evolution finds solutions to complex problems.

Scientists are already aware of several tricks employed by certain species. For instance, elephants have about 20 copies of the TP53 gene, which suppresses tumors, whereas humans have just one, located on chromosome 17.