New test could help preserve endangered gibbon populations

A Leicester geneticist working with ape specialists at Twycross Zoo has developed a test which could help preserve highly vulnerable Gibbon populations from extinction. 

Almost all 20 species of gibbon are either endangered or critically endangered with their main threats being habitat loss and the exotic pet trade. Although captive breeding programmes exist, it is extremely difficult to tell some species apart from another, with unknown hybrids unable to be released into the wild. 

Now geneticist Dr Lauren Lansdowne, while a PhD student at the University of Leicester, supervised by Dr Richard Badge, Associate Professor in Bioinformatics, has developed a genetic test to reliably determine the species of an individual gibbon. The results have now been published in Conservation Genetics Resources.

Dr Lansdowne collaborated with researchers at Twycross Zoo, the University of Tokyo and 19 other zoos across Europe so that she had large scale samples from over 200 gibbons to work with. 

Her simple genetic test was able to confirm the species of gibbons in European zoos, and identified a few individuals who may have hybrid ancestry.

 

Dr Lansdowne, who spent three months on placement as part of her PhD at Twycross Zoo, said: “Gibbons are highly charismatic small apes, closely related to the great apes but face extinction. Although captive breeding programmes ensure populations are maintained away from the threats in the wild, it is vital that these populations are healthy.”

The test entails extracting DNA from a biological sample (such as hair or blood), and sequencing a small section of DNA which is highly variable between species, allowing identification based on the DNA sequence.  

Twycross Zoo was among those who provided gibbon samples.

Dr Lansdowne said: “Some species of gibbon are able to interbreed and produce hybrid offspring. If this happens, it potentially threatens the genetic integrity of the population(s). Historically, records of wild-caught animals sold to zoos were not always complete or accurate, and a particular difficulty with gibbons is that some species look very similar to each other, making it challenging to tell them apart. This means there could be unknown hybrids in captive populations. 

“This is similarly a problem for wildlife rescue centres. Confiscated gibbons usually have little or no documentation about where they came from or what species they are. Unscrupulous traders may breed different species together, creating hybrids. If rescue centres cannot be certain what species an individual is, or if it is a hybrid, it cannot be released back in to the wild. Instead, it faces a lifetime in a rescue centre, placing considerable strain on the centre’s resources as gibbons can live for over 25 years in captivity.

“This test provides an easy way for zoos and rescue centres to assess their gibbon populations, providing important information to help guide future breeding, release, and welfare decisions.”

Dr Badge said: "Dr Lansdowne's study, one chapter of her PhD thesis, is an excellent example of how research by students in the Department of Genetics, Genomics and Cancer Sciences at the University is having real world impact for the protection of endangered species, both in the wild, and their genetically informed management in captivity. We really hope this simple test will make a difference in protecting our smallest ape relatives."

Lynsey Bugg, Twycross Zoo Director, added: “Genetic research like this is a powerful tool in helping us understand and protect endangered species. At Twycross Zoo, we’re proud to play a role in safeguarding gibbons, and studies like this support our efforts to preserve healthy, sustainable populations for the future.”