UCT scientists lead study that uncovers four distinct giraffe species

In a ground-breaking research study, scientists uncovered four distinct species of Africa’s much-loved gentle giant: the giraffe, which is quite the opposite to the widely assumed notion that just one specie exists.

This distinction was confirmed in an interdisciplinary research study that analysed the skull morphology of giraffes. And with just 117 000 giraffes left in the African wild, these findings demonstrate the importance of shining a spotlight on the silent extinction of these gentle giants. The enormous collaborative research project was conducted by scientists at the University of Cape Town (UCT) in collaboration with partner institutions like the Giraffe Conservation Foundation, the Universidad Autónoma de Madrid, other European institutions, as well as African government partners.

Uncovering four species

During the research process, scientists studied and discussed giraffe taxonomy and evolution at length and different theories emerged. However, genomic research conducted by the Giraffe Conservation Foundation and the Senckenberg Biodiversity and Climate Research Centre, has shown the distinction of four giraffe species. They’ve been around for close to a decade and include the masai, northern, reticulated and southern giraffe.

In this study, researchers assembled the largest known dataset for any medium to large wildlife by 3D, scanning 515 giraffe skulls from African national parks, game farms, taxidermists, and museum collections globally. Using 3D geometric morphometric analysis, the study showed distinct differences between male and female giraffe skulls. And the four genetically distinct giraffe species also have different cranial morphologies largely linked to their ossicones (the bony horn-like structures on their skulls).

“This study is a fantastic example of successful interdisciplinary collaboration in science that has made an important contribution to giraffe conservation.”

“This study is a fantastic example of successful interdisciplinary collaboration in science that has made an important contribution to giraffe conservation and will hopefully go a long way to saving giraffes in Africa,” said Professor Anusuya Chinsamy-Turan, a palaeobiologist in UCT’s Department of Biological Sciences and one of the study’s co-authors.

The value of science

For Dr Nikolaos Kargopoulos, the study’s lead author and a postdoctoral fellow in the Department of Biological Sciences, who travelled the world to 3D scan giraffe skulls, the findings highlight the value of science to increase scientists’ understanding of the natural world.

“When I embarked on this project, I did not expect to find such clear differences in the skull shapes of giraffe. Before I started looking closely, I thought a giraffe is just a giraffe,” Dr Kargopoulos said.

Interestingly, the development and evolutionary significance of the ossicones is key to understanding giraffe diversity and the dynamics between the different taxa. And according to Dr Jesús Marugán-Lobón from the Universidad Autónoma de Madrid, the study demonstrates that ossicone variation in each species is closely linked to the giraffe’s eye sockets, which tells scientists that ossicones and field of vision likely evolved together.

Scientists believe that the four distinct giraffe species have clear implications for their conservation and the findings play an integral role with understanding the science behind it – a step towards applying these findings in biodiversity conservation.

Dr Julian Fennessy, director of Conservation at the Giraffe Conservation Foundation and study co-author, said for almost a decade scientists genetic research proved that the four species exist, and finally the collaborative morphological research confirmed this.

“It’s about time that the world stands tall for giraffes, in particular the International Union for Conservation of Nature and changes the outdated taxonomy of giraffe that some still hold on to,” Dr Fennessy said.

“Conservation efforts need to urgently target all four giraffe species – in particular those with precariously low numbers – before it is too late.”

“Conservation efforts need to urgently target all four giraffe species – in particular those with precariously low numbers – before it is too late. Science is science and facts are facts. I hope that any debate around giraffe taxonomy is now finally put to bed, as we must act now to save each of these iconic giraffe species and the Giraffe Conservation Foundation will remain on the forefront of this battle.”