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New study confirms four distinct giraffe species, unlocking crucial insights for conservation efforts

New study confirms four distinct giraffe species, unlocking crucial insights for conservation efforts
A baby Southern giraffe baby.(Photo: Giraffe Conservation Foundation)
Julia Evans
By Julia Evans
9 Jan 2025
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Historically, giraffes were thought to belong to a single species. A new UCT study confirms the startling truth that there are, in fact, four distinct giraffe species.

Groundbreaking genetic research in 2016 revealed an unexpected truth: there are, in fact, four distinct giraffe species. Much as there are three elephant species (African savanna elephant, African forest elephant and the Asian elephant), there are four giraffe species.


While there were theories of differences in the appearance of different giraffe species, no study had ever analysed this systematically before.

But now, a new study by the University of Cape Town (UCT) and Giraffe Conservation Foundation has added another critical piece to the puzzle, using 3D scanning technology to confirm these genetic findings through skull morphology. 

The study, Heads up – Four Giraffa species have distinct cranial morphology, published in December 2024, is the most extensive of its kind, involving 3D scans of 515 giraffe skulls sourced from African national parks, museums, game farms, and taxidermists. 

Led by UCT researchers and the Giraffe Conservation Foundation, with key collaborators from the Universidad Autónoma de Madrid, other European universities, and many African government partners, this ambitious project spanned multiple continents and years.

It utilised advanced 3D geometric morphometrics, a powerful tool that allowed scientists to map and compare the intricate structures of giraffe skulls with unparalleled precision.

Skull shape the key 


Researchers were quite surprised that the results confirmed the existence of four distinct giraffe species in line with previous genetic analysis. The four genetically distinct giraffe species have distinct cranial morphologies, largely linked to their ossicones (the bony horn-like structures on their skulls).

“Initially, I thought a giraffe was just a giraffe. The distinct differences in their skull shapes were a revelation,” said Dr Nikolaos Kargopoulos, lead author and post-doctoral fellow at UCT and the Giraffe Conservation Foundation, who travelled the world to 3D scan giraffe skulls.

Dr Kargopoulos explained to Daily Maverick that researchers had known that there were four individual giraffe species since 2016, with genetic studies showing the first true data. 

“But there is no consensus of when a cluster is unique enough to be called a species — so apart from DNA we need more evidence to show they’re not just different clusters, but different species.”

Southern giraffe in Northwest Namibia. (Photo: Giraffe Conservation Foundation)



Northern giraffe in Murchison Falls National Park, Uganda. (Photo: Giraffe Conservation Foundation)



He said the true problem was that we didn’t have a consensus on what a species was: “Species is one of the most fundamental concepts in biology, but we don’t have a perfect way to describe it.”

Kargopoulos continued: “Is it two animals that look the same? Is it a group of organisms that cluster together in DNA analysis? Is it a population that reproduces successfully and is isolated?

"So the only true way to tell that two animals or two plants or two bacteria are different is to approach this from many perspectives. Some people are working on genetics, some others are working on ecology, some on coat patterns, some others are working on skeletons.

“That’s why it’s important what we did because it’s another piece of the puzzle that was missing.”

The reason this is important is for conservation


There are 117,000 giraffes remaining in the wild in Africa. The problem is, if you group that as one species, their conservation status is not as severe.

The International Union for Conservation of Nature (IUCN) assesses the conservation status of species through its Red List,  and is an important resource for informing conservation policies. Currently the union lists giraffes as a single species with a “vulnerable” status.

“But what if what we are seeing is not one species, but four. And these four are not grouped in equal numbers,” said Kargopoulos, emphasising that the northern giraffe and the reticulated giraffe species numbers were very low.

The taxonomic and conservation status of all four giraffe species is constantly updated by the Giraffe Conservation Foundation, in close communication with the committees of the union’s Red List. Its current knowledge on the four species can be summarised as:

  • Southern giraffe: Least Concern (49,850 left)

  • Masai giraffe: Endangered (45,400 left)

  • Reticulated giraffe: Endangered (15,950)

  • Northern giraffe: Critically Endangered (5,900)


“For almost a decade our genetic research has proven that four giraffe species exist, and now our collaborative morphological research has further confirmed this,” said  Dr Julian Fennessy, director of conservation at the Giraffe Conservation Foundation, and co-author.

“It is 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 hang on to.”

Fenessy added: “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.”

Stephanie Fennessy, executive director at the Giraffe conservation Foundation and co-author, concluded: “Ultimately, the old adage remains true: we can only save what we know.”

Unlocking the secrets of the ossicones


One of the study’s key insights lay in the ossicones.

Giraffes have three large Ossicones (bony horn-like structures atop their skulls) — there are two that develop above their eyes, but they also have a central one between their eyes and nose. Males have more distinctive ossicones than females, and the researchers found the most striking differences in the central ossicones in males throughout the four species.

“As we go from South Africa to Niger, this third (central) ossicone grows,” said Kargopoulos.

Giraffe distribution map. (Image: Giraffe Conservation Foundation)



“So in South Africa this skull is very flat in the central forehead (in this point), but as you go up through Tanzania and Zambia and into Kenya, you will see in the Masai giraffe, the ossicone becomes bigger, and then in northern Kenya, the reticulated giraffe, it’s bigger, and the biggest difference is in the Northern giraffe, to Chad and Niger.”

Kargopoulos explained that, as is the case with all mammals that had cranial ornaments like horns or ossicones, these were very important for reproduction.

Larger ossicones in males make them more intimidating during fights with other males over territory, and more appealing to females looking for a mate — so ossicones enable males to be dominant over other males in a territory, and they are an evolutionary factor that could potentially give some species distinctive value.

Technology expediting conservation


“If we had decided to work on this project 20 years ago, we would have a very different result, because the tools that we would have used would have been much simpler, and they wouldn’t show us what we see now,” said Kargopoulos. 

A male Masai giraffe. (Photo: Giraffe Conservation Foundation)



A female southern giraffe in Kruger National Park, Limpopo, South Africa. (Photo: Julia Evans)



A female Masai giraffe. (Photo: Billy Dodson / Giraffe Conservation Foundation)



A baby southern giraffe. (Photo: Giraffe Conservation Foundation)



A similar analysis of giraffe skulls was conducted over 20 years ago as part of a PhD project. While an excellent state-of-the-art study for the time, it reflected the tools of the time, and relied on 2D geometric morphometrics using photographs.

Over the past 25 years, the development of advanced software and the rise of 3D modelling have transformed the field. Researchers can now choose more precise landmarks for comparison, analyse overlapping structures, and apply complex statistical tests to identify significant differences in shape. 

Kargopoulos emphasised that this leap forward had made it possible to distinguish subtle differences that were previously unclear due to technological limitations.

The geometric morphometrics method involves creating 3D models of skulls, not just 2D photos, which allows researchers to standardise and compare shapes with more precision. Kargopoulos explained that the process began by scanning skulls with a 3D scanner to generate digital models. Then specific points, known as landmarks, were identified on each skull to capture critical features for comparison. The models were then scaled, rotated, and aligned, ensuring that differences in size or orientation were minimised, leaving only the variations in shape for analysis.



“The question wasn’t if there were differences, but if it was statistically significant,” said Kargopoulos, and to his surprise — it was. DM

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