Scientists say that due to hunting by humans over the past century, the horns of rhinos have become shorter.
Decades of poaching of the big-horned rhinos means that only the small-horned rhinos remain and pass on their genes to the next generation.
Published in the journal People and Nature, the results of the research by Cambridge University experts are based on a review of photographs of rhinos taken over a period of 140 years. These images are of all species of rhinoceros including black, white, Indian, Javan and Sumatran rhinos.
The study’s lead author, Oscar Wilson, said the scientists were pleased to have found evidence in the images that rhinos’ horns have shortened over time.
He said that working on these animals is probably the most difficult task because of security issues.
Oscar Wilson said that rhinos grew their horns for a special reason. Different species used them in different ways such as to help in obtaining food or to defend against predators. Therefore, scientists believe that having small horns would be detrimental to their survival.
The researchers measured the horns of 80 rhinos photographed between 1886 and 2018.
