- Researchers study populations of Asian elephants in Myanmar, Southeast Asia
- Elephant siblings affect young offspring from early life to late life
- In males, survival rates were lower with older sisters but higher body weight
If you’ve ever felt held back in life by your older brother, a new study suggests that humans aren’t the only ones.
Today, scientists report that elephants benefit more from having older sisters than older brothers when they grow up.
Academics studied semi-captive populations of the Asian elephant (Elephas maximus) in Southeast Asia in Myanmar.
They found that female calves raised with older sisters lived longer and reproduced two years earlier than brothers, although it is not certain why.
Pictured, Asian elephant siblings. Overall, the presence of an older sibling of either sex in the Asian elephant (Elephas maximus) population in Myanmar increased the long-term survival of the calf compared to the absence of a sibling, researchers report.
Situation In danger
population less than 50,000
scientific name the biggest elephant
Height 6.5–11.5 feet
Weight about 11,000 pounds
Length about 21 feet
Overall, Asian elephant siblings affect their young offspring from early life, when they are calves, until late life, academics claim.
Growing up with older siblings increased the longevity of calves, the experts found—but older sisters had a bigger impact in this regard than older brothers.
The study has been conducted by researchers from universities in Finland, UK and Myanmar and is published in the British Ecological Society Journal of Animal Ecology.
“Our research confirms that sibling relationships shape individual life, particularly in social species, such as elephants, where cooperative behaviors are essential to the growth, survival and fertility of individuals,” Lead author Dr. Finland.
Researchers used a large, multi-generational dataset of state-owned, semi-captive Asian elephants to look at the effect of older siblings’ presence and gender on body mass, reproduction, sex and next-calf survival. .
Study of semi-captive Asian elephants in Myanmar finds that calves benefit from having older sisters than older brothers
The records included information on breeding and longevity of 2,344 calves born between 1945 and 2018.
In female elephants, those raised with older sisters are more likely to live longer and breed for the first time an average of two years earlier than older brothers.
Reproduction at an earlier age is generally associated with more offspring during an elephant’s lifetime.
Researchers found that in male elephants, older sisters had lower survival rates but higher body weight
Among male elephants, those raised with older sisters had a lower survival rate, but a higher body weight than those raised with older brothers.
For males with older sisters, it may be that the positive initial increase in body mass may outweigh the cost of living later in life.
As the study was correlative, influences of external factors outside sibling effects, such as the quality of maternal care and the workload and management of the elephants, cannot be excluded.
“By collecting more information about mothers’ body mass at birth, we hope to separate maternal effects from sibling effects,” Berger said.
‘More data will allow us to explore the effects of the environment on sibling relationships and go into greater detail on the effects of siblings on specific aspects of small calf health, such as immunity, muscle function and hormonal variations.
‘We can also examine the effect of gender on the life history trajectory of the large calf and the appearance of small calves.’
The study was conducted on state-owned Myanmar wood elephants that live in forest camps distributed across the country and are considered ‘semi-captive’.
Elephants are used during the day as riding, transport and draft animals. At night they remain unprotected in the woods and can interact and mate with both wild and domesticated elephants.
The calves are reared by their mother until the age of five, when they are trained for work. The Myanmar Timber Enterprise (MTE) enforces rules on the daily and annual workloads of elephants.
UnfortunatelyThe Asian elephant is classified as endangered on the IUCN Red List of Threatened Species.
According to the Zoological Society of London (ZSL), it is under increasing pressure in the wild due to habitat destruction through human population growth.
As human populations continue to grow, elephants naturally have less living space and are forced into smaller areas and more conflict incidents with people.
The African savannah elephant (Loxodonta africana) is also being driven to extinction due to hunting and is currently listed as ‘Vulnerable’ on the IUCN Red List.
African savanna: the largest land mammal in the world
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As they walk, they push trees to reach their branches and roots, help maintain grasslands, and they use their teeth and trunks to dig for water. , giving many other animals what they need to survive.
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