Fossils do not arrive with names attached. A skull fragment from one country and a limb bone from another may receive different names before researchers have enough overlapping material to compare them. Later discoveries can reveal that the apparent diversity lies partly in the history of collecting and description.
That is the problem Kostantis Laskos and Dimitris S. Kostopoulos addressed for the last European giraffid, a member of the wider giraffe family known as Palaeotragus inexspectatus. In a study first published online in 2024, they described additional Greek remains and revisited earlier finds. Similarities across skulls, teeth and limb bones strengthened the case that almost all the relevant Eurasian material represented one species, despite its several historical names.
The argument did not depend on every fossil looking identical. It depended on whether the differences were strong and consistent enough to justify separating animals that otherwise shared a recognizable anatomical pattern.
More names than complete skeletons
Earlier researchers had described remains from Romania, Greece, Tajikistan and the northern Black Sea region under names including Mitilanotherium, Macedonitherium, Sogdianotherium and Palaeotragus. Subsequent comparisons had already proposed bringing some or all of them together. The new paper tested and extended that interpretation with more material; it did not invent the single-species hypothesis from nothing.
Laskos and Kostopoulos studied new or previously undescribed material from Dafnero-3, Volax, Tsiotra Vryssi and Krimni-3, and redescribed remains from Dafnero-1. The Greek sites span different parts of the Early Pleistocene, with Dafnero around 2.3 million years old and some of the younger material around 1.5 million years old.
The specimens offered different pieces of the comparison. A partial skull preserved its ossicones, the bony head projections of giraffids. Jaws retained adult or juvenile teeth. Limb bones supplied joint surfaces, shaft proportions and the shapes of ridges and grooves. Together, they allowed the authors to ask whether a repeated combination of features appeared across sites.
The skulls agreed despite their damage
The Greek skull material showed important similarities. The ossicones were widely separated, positioned above the eye sockets and inclined forward. The roof of the skull was concave between them, while the part behind the eyes was elongated. Several of these features could also be compared with material from other Eurasian localities.
Ossicone length varied, but the shafts had similar overall form and broadly comparable basal dimensions. A complete ossicone from Tsiotra Vryssi was longer than others in the comparison. That difference did not, by itself, establish another species when the shape and the rest of the anatomy agreed.
Preservation imposed limits. Some skulls were badly damaged or distorted, and one locality’s material might preserve a feature that another lacked. The authors therefore did not treat the absence of a visible feature on a broken specimen as straightforward evidence that the living animal lacked it.
This is one reason the rest of the skeleton mattered. A conclusion based on one distorted skull is less secure than an interpretation supported by several independent anatomical regions.
Teeth and limbs added a second check
The teeth supplied further agreement in size and form. In particular, some lower premolars—the cheek teeth in front of the molars—had a partly molar-like construction. Comparable arrangements occurred in both adult and juvenile dental material, making the pattern more informative than an unusual feature on a single worn tooth.
One adult lower jaw also revealed a conspicuously short premolar row relative to its molar row: the former was about 56% of the latter’s length. That proportion helped refine the species’ diagnosis and distinguish it from several earlier Palaeotragus forms. But the paper’s comparison graph makes the limitation visible: the value for this species came from one jaw. It is a useful observation, not a fully sampled range of variation.
The limbs provided another set of matching details. Forearm bones shared the form of a roughened attachment area and the relative positions of their wrist-joint surfaces. The long lower-limb bones had recurring patterns of grooves and joint facets. The ankle bones also shared a comparatively square, symmetrical shape.
The researchers assessed proportions as well as absolute size. For a long bone, they compared shaft breadth with overall length to describe how robust it was. This helps distinguish a generally larger specimen from one whose proportions are different. Their single-species interpretation rested on the combined morphological and measurement evidence, rather than one size threshold.
Two uncertainties that remained separate
The study found some hints that younger Greek limb bones were shorter and more robust than older examples. The authors considered a possible change through time, but judged the sample too limited for a firm hypothesis. Calling the material one species did not require pretending that no variation existed within it.
The Iberian remains received a more cautious treatment. They were scarce, some upper premolars lacked a fold seen in other samples, and a metatarsal was unusually elongated. The authors retained Palaeotragus cf. inexspectatus: a qualified identification indicating comparison with the species while leaving room for uncertainty.
There was also a separate question about the genus. Even if the Eurasian samples belong to one species, where should that species sit among earlier giraffids? Laskos and Kostopoulos favored Palaeotragus, based on the overall combination of skull, dental and skeletal features. Other researchers have favored retaining Mitilanotherium. The paper acknowledged that a comprehensive phylogenetic analysis was still needed.
Why a revised name changes the story
Grouping fossils differently changes the diversity one infers from the record. Several named forms can suggest multiple lineages; one broadly distributed species suggests a different evolutionary history. That is why the anatomical comparisons must come before sweeping claims about diversification or extinction.
The paper also discussed ancestry, diet and eventual disappearance, but those broader interpretations do not acquire equal certainty merely because the taxonomic case becomes stronger. Nor does assigning these fossils to the giraffe family make them demonstrated direct ancestors of living giraffes.
Our giraffe science library follows that family through a much richer fossil record than the living species alone suggest. This study clarifies one late part of it by showing how new bones can reduce apparent diversity: the decisive evidence was the repeated agreement of many anatomical details, while the exceptions remained visible in the classification.
Sources
Kostantis Laskos and Dimitris S. Kostopoulos (2024, online; 2025, issue). “On the last European giraffe, Palaeotragus inexspectatus (Mammalia: Giraffidae); new remains from the Early Pleistocene of Greece and a review of the species.” Zoological Journal of the Linnean Society 203, zlae056. Full paper.
