Monday, February 3, 2014

Dominance in Elephants: Who is in Charge Here?

by Lisa Barrett


Imagine your great grandmother always picking which restaurants your sisters, aunts, and mother will go to while your teenage brother leaves the family and joins a group of other men…

How do elephants pick a leader? Who is next in the chain of command? This blog will answer your questions about dominance in elephants.

Like many animals, elephants form a hierarchy within their social structure, thereby reducing conflict over resources (such as food, water, and space).  In elephants, a matriarch (the oldest and wisest female) leads her bond group of related females to find food and water and to avoid predators. If the herd becomes too large for the available food or water supply, some of the females might split off from the herd and form their own groups, each headed by an older relative. In this way, we know that elephants live in fission-fusion societies. However, scientists are still investigating the complexities of elephant social structure. 


Matriarchs have great memories for where water is located.

Dominance in males is a little different than that in females, or cows. Males, or bulls, form bachelor herds when they reach sexual maturity. For example, while the dominant cow is the herd leader, the dominant bull is usually the individual that mates with the most females and beats out other males in contests of strength. Interestingly, dominant bulls who are in musth tend to remain in musth (and maintain a higher production of testosterone) longer than younger, less dominant bulls. Read more about musth here: http://bit.ly/1eJSCyj.


Male elephants may become aggressive when they go into musth.

Photo by: Lisa Barrett

In male elephants, there is a possibility of a takeover. Bulls who enter musth but are lower-ranking may challenge the dominant individual to gain a temporary access to females who are in estrus. In fact, being in musth gives males an advantage over non-musth males, because a chemical secretion signals to females that they are ready to mate. This process, in which different bulls enter musth and get access to females, allows for a fair system of which males get to mate and also makes the population genetically diverse. Interestingly, an alternative reproductive strategy has evolved in which males enter musth when dominant males are not in musth.

Fighting over access to females is risky. It usually involves two males clashing together their long, ivory tusks, rearing on top of one another, and perhaps sustaining injury (including breakage of tusks) or even death. The winner usually gains priority access to females—talk about making sacrifices in the name of love!


Two male African elephants fight with their tusks.

Photo by: Caitlin O'Connell and Timothy Rodwell

It is important for conservationists to remember that poaching wild elephants not only causes a traumatic instant for the families of the elephants being killed, but it also has devastating, long-term consequences. After all, if the eldest female (or male) elephant is no longer part of the herd, she cannot impart her knowledge to her family members, and so younger elephants have no leader from which to learn. This has already proven to be catastrophic for young male African elephants who, without an older male to guide them, became highly aggressive and attacked many humans and rhinoceroses. Therefore, the wisdom of dominant individuals is critical for the rest of the herd to learn how to behave and survive. 

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