A tiny report in The Times newspaper today indicates that something very serious is happening in terms of conservation of both the rhino and the elephant. The Times report states that rhino horns across all species have shrunk in the past century. Scientists believe that hunting is the probable cause.
The findings have been published in the journal People and Nature. They were based on an analysis of 140 years of photographs. The poachers target rhinos with longhorns. This results in the rhinos with shorter horns surviving with the opportunity to procreate and produce more rhinos with shorter horns and so on.
Artificial selection or rhinos and elephants
In effect, the poachers are engaged in artificial selection a.k.a. selective breeding of rhinos. And the same can be said about elephants.
This phenomenon occurred in Gorongosa National Park, Mozambique. It is another example of how human intervention interrupts the course of natural selection through artificial selection by culling certain types of elephant and rhinoceroses leaving the remainder to procreate and pass on their genes.
In both instances, the genes passed on are from elephants and rhinoceroses with shorter tusks or no tusks or shorter horns in the case of rhinos.
Long term future: rhinos without horns
An interesting observation is the obvious one namely that if poaching continues as it is of rhinos over a long time, there will come a time when rhinos no longer have horns. That would seem to be nature’s way of protecting the rhino.
The picture on this page comes from an article on the PHYS.ORG website. The colour photograph above is of an Indian rhino at Whipsnade Zoo, UK. The photograph is by Oscar Wilson.
The black-and-white photograph is in the public domain, and it is of Theodore Roosevelt standing behind a black rhino that he had just killed in 1911. You can see the enormous difference in the size of the horns.
As a consequence, researchers from the University of Cambridge who measured the horns of 80 rhinos decided that rhino horns had become smaller over time because of intensive hunting.
Oscar Wilson, formerly a researcher in the University of Cambridge’s Department of zoology and who wrote the report on the study said:
“We were really excited that we could find evidence from photographs that rhino horns have become shorter over time. They’re probably one of the hardest things to work on in natural history because of the security concern”.
Poaching hard to stop
You probably know that rhinos are heavily protected on the African continent but despite this sometimes poachers simply walk into reserves and national parks pretending that they are tourists having bought a ticket to the park and then shoot the rhinos and strip away their horns.
Harsher punishment of poachers is needed plus international pressure on Beijing.
Value of rhino horn
On the black-market rhino horn prices can fetch up to US $400,000 per kilogram for the Asian rhino and up to US$20,000 per kilogram for African rhino horns. The rarer the rhino the more valuable the horn and the more likely the animal will be killed. It is a vicious downward cycle.
Rhino horn is keratin
Rhino horn is made of keratin, the same material that our hair and our nails are made of. Rhino horn is used in Traditional Chinese Medicine based upon superstition. It is also used in Vietnam and possibly other Asian countries. My research indicates that there is little if no scientific support for any health benefit in eating rhino horn as you would expect as it is keratin.