Commonly seen as the icon for the African savanna, the elephant silhouette is well-known and well-loved by people all over the world. But how would this silhouette look without tusks? A study from the 2000s reported that 98% of female elephants were without tusks in the Addo Elephant National Park. Here, Megan Huntley explores why this is occurring, and the wider impacts of this problem.
As with many conservation problems, the primary cause of this problem is poaching. Ivory, which tusks are made of, is still an extremely valuable commodity and has been used to fund weapons and ammunition in civil wars, such as that seen in Mozambique in 1977. Despite conservation efforts, poaching still remains prevalent, and now seems to be influencing the evolution of the elephants.
How is poaching influencing evolution?
The premise lies with the idea of natural selection, and the survival of the fittest. If elephants are targeted for their tusks, naturally it becomes an advantage to have the tuskless gene, which organically occurs in about 4% of elephants; these individuals are not targeted for ivory. Untargeted elephants then survive and pass on their tusklessness to the next generation. Over time, the tuskless gene has flourished amongst both African and Asian elephant populations.
What does this mean for the elephants?
To understand implications, it is first a good idea to look at how elephants use their tusks.
The most common uses for tusks are foraging, digging, stripping tree bark, moving vegetation and obstacles, battling others, attracting mates and fending off predators (mainly used by juveniles). Needless to say, tusks are a pretty useful tool.
Although there appear to be no negative health impacts of a lack of tusks, studying the above uses could suggest some problems.
A noticeable issue is the lack of ability for juvenile elephants to defend themselves from predators. This may lead to increase of infant mortality among elephants, something which could develop into a larger problem given the endangered status of elephant populations.
Eating habits may also have to change, influenced by a lesser ability to dig and strip tree bark. However, elephants are diverse in their foraging techniques, with their trunks playing a key role in reaching vegetation. So, diet change may not be so much of an issue. Changes in paternal and mating behaviours may also be observed.
What does this mean for the environment?
Elephants are known as “landscape architects”. We’ve all seen videos of elephants knocking over trees and pulling down branches with their trunks. Aside from being entertaining to watch, they play a vital role in the upkeep of ecosystems. Tusks are used to make clearings, allowing less dominant plant species to thrive, and maintaining the open structure of the savanna that is so familiar.
Elephants also use their tusks to dig for water during the dry season, creating water sources for other species. With the acceleration of global warming, the dry seasons of the savanna are likely to become more intense. A loss of tusks suggests a loss of opportunities for water sources, not only for the elephants, but reliant species too. This may cause greater species decline during these dry seasons.
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