In 1977, a female rhino named Nasi was born at Dvůr Králové Zoo. Her birth was surprising because her mother, a northern white rhino named Nasima, had only mated with a different species. Nasi stood out as the only known hybrid between northern and southern white rhinos. Sadly, northern white rhinos are now critically endangered, with only two females left: Najin and her daughter, Fatu.
In 2023, scientists made a significant leap in conservation by successfully performing in-vitro fertilization (IVF) to create a rhino embryo. They initially used eggs from Elenor, a southern white rhino, which were implanted into a southern white rhino named Curra in Kenya. However, tragedy struck when Curra fell ill due to a bacterial infection. Doctors found a 70-day-old fetus during her necropsy, proving that the IVF process worked.
Despite the heartbreak, there’s hope. The team plans to use eggs from Fatu for another IVF attempt. This situation raises a question: Will transferring embryos between the two species complicate things? Jan Stejskal, a coordinator of the BioRescue project, believes the success of a hybrid like Nasi gives reason to believe in the viability of southern white rhinos as surrogates for northern whites.
Stejskal stated, “We don’t know if there might be some barrier. But, given that we had Nasi born, it gives us a good indication.” The goal is clear: create healthy northern white rhinos, despite the challenges of dwindling genetic diversity.
Northern white rhinos have faced drastic population losses, which greatly reduces genetic variability. This is a significant issue because genetic diversity helps populations survive diseases and adapt to changes. As Matt James from Colossal Biosciences pointed out, “When you lose a lot of your population, you lose a lot of genetic diversity.”
To counteract this, the BioRescue team is exploring the genes of historical northern white rhinos. By examining what traits they had, scientists aim to restore some lost genetics through gene editing. This could improve adaptability and resistance to diseases.
The overall approach involves collaboration between multiple organizations, showing a multi-faceted attempt to save one of Africa’s iconic species. It’s a narrative that mixes hope with innovation, and the hope is that soon, we’ll hear the sound of baby northern white rhinos.
For more on the challenges of conserving endangered species, you can check out the BioRescue project.
