Can a 'Frozen Zoo' bring back the rhino?
In a small room in southern California lie the frozen ingredients which could resurrect an extinct species.
The 'Frozen Zoo' now has tens of thousands of samples safely stowed away but it's the 12 cell lines they have from the northern white rhino that are set to result in a world first.
For more than 40 years, a team at San Diego Safari Park has been collecting the cells from endangered animals and storing them in a deep freeze.
"We think it's the world's largest, most diverse ... and most utilized collection of its kind," says Dr Oliver Ryder, the director of genetics at the San Diego Institute of Conservation Research.
"We were very confident from the beginning that the purposes for such a collection could expand," says Dr Ryder. "Little did we know how much."
When the Frozen Zoo started in 1975, there were about 500 northern white rhinos in the wild. Initially found in east and central Africa, their numbers were already starting to dwindle at the hands of poachers.
By 1984, there were just 15.
Despite a massive conservation effort at Garamba National Park in the Democratic Republic of Congo that initially saw the sub-species' numbers double - a combination of ruthless poaching and two wars saw the rhinos presumed extinct from the wild by 2008.
Today just three northern whites remain in the world - a male, Sudan and two females, Najin and Fatu. They live at Ol Pejeta Conservancy in Kenya but sadly can no longer reproduce naturally.
As far as Dr Ryder is concerned, that means the northern white rhino is already extinct.
"The dictionary definition of extinction is when the last individual of a species dies," he says. "But to a geneticist, extinction takes place when there's no longer any possibility of reproduction. So you can have living animals but ... the future of the species is gone. That's what extinction is."
But if Dr Ryder and his team at the Frozen Zoo can help it, they won't be "genetically extinct" for long.
The plans are bold. The first is essentially mastering rhino IVF - work out how to safely extract eggs from Fatu and Najin and then fertilise them with frozen sperm.
"We're using some tried and true methods," says Dr Barbara Durrant, director of reproductive physiology.
"Some techniques that have been used for decades in cattle and horses, and pigs and humans but we're applying them for the first time to rhinos ... It's kind of a race against time... to collect eggs from those two females and to possibly collect sperm from the last male, Sudan."
The second plan to resurrect the northern white is considered a longer term goal - making stem cells from rhino skin tissue they already have stored and creating an embryo from that.
This incredible method was devised by Japanese scientist Shinya Yamanaka in 2006, who worked out how to reprogram any mature living cell into a stem cell. Prior to this breakthrough, it was only possible to get stem cells from embryos. Now, they can be grown from a skin biopsy.
Once there's a stem cell, they can be turned into any cell, such as eggs or sperm. However, while scientists have managed to turn rhino skin tissue into stem cells, beyond that has so far only been successful in mice.
"It's a huge step and we do recognise that a mouse is not necessarily the best model for a rhinoceros, but it's proof of principal," says Dr Durrant.
"We don't know how difficult it's going to be in the rhino, some of the problems will be different to those encountered when doing this with a mouse, but we know it can be done."
Whichever way these scientists get a northern white rhino embryo, the goal then is to implant it in a cousin of the sub-species, the southern white rhino.
San Diego Safari Park has brought over six reproductive females from Africa specifically to act as surrogates. Prior to this though, they also need to attempt and perfect embryo transfer in a rhino species.
"We can't take a chance in putting a Northern White Rhino into a Southern White Rhino and not know what we're doing and not know that we're going to be successful," says Dr Durrant.
"If everything went perfectly the first time ... we think we could have a Northern White Rhino calf on the ground in 7-10 years but that's given everything going perfectly the first time which we know will not happen."
"Realistically, I would be thrilled if we had a Northern White Calf in 10 years [but] we look at this project as very long term, at least a 20 year project if not longer."
Dr Ryder is optimistic, but also realistic about their chances of success.
"Will we be capable of de-extinction of the northern white rhino? I'd like to think we can beat the race and have a baby northern white rhino from the utilization of advanced genetic and cellular technologies before the last one born in the wild dies ... but I don't know whether that will be possible."
Of course this begs the obvious question — is there a potential for a real-life Jurassic Park?
"In a way ..." laughs Dr Durrant. "The cells that we have in the Frozen Zoo and other people have around the world that they've frozen can be used in this way to bring back species from the brink of extinction."
"To us it doesn't mean bringing back long extinct species, that's not something we're interested in doing ... People would love to see a dinosaur, a real dinosaur. The problem is there's not good DNA from dinosaurs ... But the bigger question in our minds is what would we do with them?"
Dr Ryder says this technology opens up many doors but there needs to be policy regarding its use.
"There will be a line and it's the people that are alive today that are going to start drawing it," says Dr Ryder. "The degree to which we're prepared to be humbled by nature or the degree in which we insist we command or control it."
More information about our story:
DR KES HILLMAN SMITH
To learn more about Dr Kes Hillman Smith and her efforts to save northern white rhinos in the wild, please head to www.Garamba.wix.com/GarambaConservation . There you can organise to purchase a copy of her book, Garamba: Conservation in Peace & War, which details not just her work with the rhinos but the story of Garamba National Park and all those who have fought to protect this incredible park and its wildlife. Or you can organise to buy a copy by emailing one of the other authors, Dr José Kalpers, who is based in Australia, at jkalpers@gmail.com.
SAVING THE NORTHERN WHITE RHINO
If you’d like to help scientists conceive a baby northern white rhino and save the species, please donate to the GoFundMe campaign raising funds to assist in the necessary research: http://www.gofundme.com/makearhino.
To plan a trip to see the world’s last three northern white rhinos or find out more information about Ol Pejeta, head to www.olpejetaconservancy.org. The conservancy is also the largest black rhino sanctuary in east Africa and the only place in Kenya to see chimpanzees.
You can also donate money to help care for baby southern white rhino Ringo, who drinks his way through $20 worth of milk every day and requires 24/7 care and attention. From the salaries required for his human parents, to the cost of gas to cook his oatmeal, Ol Pejeta needs your help to get this baby back to the wild in great health: www.olpejetaconservancy.org/ringo
To follow the efforts of the international team working to resurrect the northern white rhino in a lab, head to sandiegozoo.org/sdzglobal. There you can also learn more about the San Diego Zoo Institute for Conservation Research (home to the Frozen Zoo) or plan a visit to San Diego Safari Park and its Rhino Rescue Center. The new center was purpose-built for six female southern white rhinos slated to act as the surrogates for a northern white embryo.
SPECIAL THANKS
To wildlife filmmaker Alan Root for giving Sunday Night permission to use vision of from his documentary, Garamba: The Impossible Elephants in order to showcase Dr Kes Hillman-Smith’s work with northern white rhinos in the wild.
And also to filmmaker Michael Dalton for granting Sunday Night permission to use vision from his documentary series, Ol Pejeta Diaries, which followed the journey of the northern white rhinos transported from Dvur Kralove Zoo to Ol Pejeta in 2009.
