Evolution in action
The poaching of elephants for ivory is simply deplorable. Even since the banning on the trade of ivory in 1989, we’re still losing around 8% of elephants to illegal poaching- nothing we have implemented has stopped this cruelty. So, elephants have taken the matter into their own hands.
Elephants all over the world have begun selecting against having tusks. Previously, Asian male elephants were born without tusks in only around 2% of cases. By 2005, this figure had grown to between 5 and 10%. In Africa, one national park estimated the number of their elephants born without tusks was as high as 38%. What we are seeing here is natural selection in action. It is uncertain whether female elephants are choosing to breed with non-tusk bearing elephants more frequently or simply that elephants without tusks have a greater chance of reaching the age of breeding- probably a combination of both.
There are many horrible aspects to this story, but perhaps the most appalling is the fact that tusk are important; they are weapons and tools that benefit elephants. Losing them means that nature has decided that poachers are a greater threat to the elephant’s existence than its diminished ability to fight and forage. Sad.
image: African elephants on the safari by Corbis
For further reading:
(BBC) British Broadcasting Corporation. 1998. World: Africa Elephants ‘ditch tusks’ to survive.
Whitehouse, A.M. 2002. Tusklessness in the elephant population of the Addo Elephant National Park, South Africa. J. Zool. 257: 249-254. http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=108817&fileId=S0952836902000845
Steenkamp, G., S.M. Ferreira, and M.N. Bester. 2007. Tusklessness and tusk fractures in free-ranging African savanna elephants (Loxodonta Africana). J. S. Afr. Vet. Assoc. 78: 75-80 http://reference.sabinet.co.za/sa_epublication_article/savet_v78_n2_a6.