The dehorning of rhinos began in 1989, making Namibia the first country to use it as an anti-poaching method. There remains a lot of conjecture surrounding the possible implications of dehorning rhinos. While the benefits of such an exercise have long been proved, some sceptics believe it could have some effect on rhino behaviour and biology. But now, new research conducted by the University of Bristol Vet School, the Namibian environment ministry and the Save the Rhino Trust has found that there are no statistically significant differences in key factors of population growth such as breeding, birth, survival, life span and death between dehorned and horned black rhinos. The study looked into four sub-populations of black rhinos in Namibia - of which three had been subjected to some level of dehorning at least once. Researchers looked closely at the age of females birthing their first calf, the average time between the birth of calves of each female, birth sex ratios, calf survival, life span and cause of death. It found that there seemed to be no evidence that dehorning harms black rhinos, which it said is extremely encouraging for the continued use of dehorning as an anti-poaching technique.