A study has found that rhinoceros horns have shrunk over the past century, with experts warning this is a direct result of poachers and hunters targeting bigger and bigger prizes.
Research published in the Journal of People and Nature showed that the phenomenon can be seen across all species of rhinos, as the animals with shorter horns are less likely to be killed by poachers, so they are more likely to survive hunts and reproduce. Rhinoceros horns are popular among trophy hunters as well as being used for medicines in Vietnam and China.
“Preferential hunting selection for individuals with larger horns or tusks resulted in individuals with smaller features surviving and reproducing more, passing on these traits to future generations, and resulting in an evolutionary change,” the researchers wrote.
The researchers came to their conclusion after studying photos of a variety of species from the past 140 years.
Oscar Wilson, the study’s lead author, fears that the widespread existence of shorter horns will lead to both more rhinos being killed to make up the shortfall as well as making it harder for the animals to defend themselves.
“This is bad news for hunters obviously, but unfortunately it’s bad news for rhinos as well, because if the hunters want the same amount of horn, they’re going to have to shoot more rhinos,” Wilson said.
“Rhinos do actually use their horns for a lot of different things, like defending their territory or finding a mate. We think this must have some effect on the way rhinos will live their lives.”
Rhinos have been designated as an endangered species by the World Wildlife Foundation, with the black rhino considered critically endangered. There are fewer than 30,000 rhinos currently in the wild.