Only children have a harder time – this also applies to Asian elephants like these wrangling young animals. If the elephant calves have older siblings, their chances of survival increase significantly, as a study confirms.
Siblings have a formative influence on our lives: Whether we grow up as an only child or have older or younger brothers and sisters influences our personality and psyche, but also our health, as many studies have shown. A study of Asian elephants in Myanmar shows that this is no different with animals either. There, researchers working with Vérane Berger from the University of Turku followed the careers of 2,344 elephant calves that were recovered between 1945 and 2018.
The elephants examined live semi-wild in Myanmar: during the day they are used for forest work or as draft animals and pack animals, at night they can roam freely in the forest. There they also interact with wild animals and mate with them. The elephant calves stay in the forest with their mothers until they are five years old, only then are they caught and trained for work.
“Because these elephants live in their natural habitats, there are many similarities with wild elephants, such as foraging for food and free reproduction,” explains Berger’s colleague Mirkka Lahdenperä. “Because there are more similarities than differences, we assume that some of the relationships that we found in our study also apply to wild elephants.”
The evaluation of the data on the elephant calves showed that it definitely made a difference whether the young elephants grew up as only children or with older siblings. If there were older brothers or sisters, this increased the calves’ chances of survival. The older sisters in particular proved to be helpful for female young animals: If they existed, the young elephant cows later produced their first calf an average of two years earlier and lived longer. Male elephant calves put on more weight early on when they had older sisters.
“Our research confirms that sibling relationships shape the lives of individuals,” explains Berger. “This is especially true for social species like elephants, where cooperative behavior is essential for the development, survival and reproductive potential of the individual animals.”