taxonID	type	description	language	source
EB5CD717CC68FFE00CA6A018FBC8F87A.taxon	description	DENTAL IRREGULARITIES 109 out of the 516 specimens in the dataset exhibited deviations from the standard dental morphology. These deviations included total absence of teeth, alternations in the orientation of one or more teeth, differences in cusp morphology (including the presence / absence of cusps), irregular dental wear patterns, and fractures. These variations are described in detail below. Absence of teeth This relatively rare phenomenon was observed only three times in our sample: twice for P 2 (106) (in NHMUK-ZD- 1902.11.13.2, G. c. camelopardalis, male, age class F, South Sudan, Fig. 2 A; and in NHMW- 5575, G. camelopardalis subsp., male, age class G, Sudan) and once for M 3 (bilaterally 111 and 211) (SMNS-Z-MAM- 45425, Giraffa sp., female, age class F, Zoo Wilhelma, Fig. 2 B). In both cases the surface of the maxilla where the tooth was missing appeared faintly rugose, but did not show any signs of trauma (e. g., breakage, secondary ossification, or any sign of healing). This suggests that the teeth were not lost, but likely never erupted. Misaligned teeth Several cases of teeth that were rotated in the maxilla were observed. In these specimens the teeth were not perfectly aligned on a smooth arch but showed positioning deviations. In most cases, only one tooth was aberrant, but occasionally multiple teeth were affected. Single-tooth deviations were seen in the P 2 (106 / 206) (n = 5), P 3 (107 / 207) (n = 2), P 4 (108 / 208) (n = 3), and M 3 (111 / 211) (n = 3; Fig. 2 C), while deviations in more than one tooth were seen in three specimens. In NHMUK-ZD- 1873.8.29.7 (G. c. camelopardalis, female, age class E, Ethiopia) only the premolars were affected, whereas in NHMW- 974 (G. t. tippelskirchi, female, age class G, Kenya) both the molars and the premolars were affected to a considerable degree. In the latter specimen the P 4 (108) was lost (Fig. 2 D), but it was not possible to ascertain whether the two irregularities were related. Irregular dental wear Nine specimens showed uncommon dental wear patterns. In six instances, a single maxillary cheek tooth was considerably worn more than the others of the toothrow. In these cases, this tooth was also much more worn than in other specimens of the same age class. In particular, this was observed on the P 2 (206) (ZIM-TCI- 181 a, G. g. giraffa, male, age class E, Zimbabwe), the P 3 (207) (FMNH- 34425, G. g. giraffa, male, age class G, Botswana), the P 4 (208) (ZIM-TCI- 472, G. g. giraffa, male, age class E, Zimbabwe), and the M 1 (109 / 209) (n = 4) (Fig. 2 E). Additionally, three individuals showed deviations in the dental wear of only parts of specific teeth. RMCA-RG- 3748 (G. c. antiquorum, female, age class E, D. R. Congo) showed an early dentine connection between the lingual and the buccal cusps, which is unusual considering the dental wear stage shown on the other teeth. Finally, ZSM- 1911 - 2446 (G. t. tippelskirchi, female, age class F, Tanzania) and USNM- 304613 (G. r. reticulata, male, age class F, Washington Zoo) showed an irregular wear pattern on the left M 1 (209), with the distal half worn more than the mesial one (Fig. 2 F). While this was more evident on the left side of the skull, the right M 1 (109) also showed a milder version of such irregular wear pattern. In general, six specimens showed such deviations on the left side of the maxilla, two on the right, and just one on both sides. Irregular dental morphology Common dental irregularities observed in the sample related to the morphological range of the cusps of the upper cheek teeth. This rarely involved the premolars, with n = 3 for P 2 (106 / 206) (with unusual cristae in two specimens and an additional lingual cusp-like structure in FMNH- 32901, G. r. reticulata, female, adult, Ethiopia; Fig. 3 A), and two specimens for P 3 (107 / 207) (USNM- 162018, male, age class F, Kenya, as well as FMNH- 32901). The specimen FMNH- 32901 also had an additional P 4 (108 / 208) cusp-like structure on both sides of the maxilla (Fig. 3 A). Two more specimens showed irregular morphology of the P 4 cristae (SI 1). Three specimens presented uncommon morphology on the M 1 (109 / 209) and one on the M 2 (110 / 210) (SMNS-Z-MAM- 45425, Giraffa sp., female, age class F, Zoo Wilhelma; Fig. 2 B). On the M 1, AMNH-M- 53549 (G. c. antiquorum, female, age class D, D. R. Congo; Fig. 3 B) retained a barrier between the mesostyle and the metacone, RMCA-RG- 3749 (G. c. antiquorum, female, age class E, D. R. Congo) had a double crista only on the left M 1 (209), while ZIM-TCI-X 3 (G. g. giraffa, male, age class F, Zimbabwe; Fig. 3 C) had a lingually expanded protocone. Interestingly, the M 3 (111 / 211) was the most commonly affected tooth. There were four cases in which this tooth had a rather peculiar morphology that differed markedly from the standard phenotype. Possibly the most extreme case is evident in specimen SMNS-Z-MAM- 49722 (Giraffa sp., female, age class I, Wilhelma Zoo), in which the left M 3 (211) was rounded, enlarged and with just faint signs of its cristae and cusps (Fig. 3 D). The most frequently observed irregularity was the reduction of the hypocone. In 56 specimens the M 3 (111 / 211) hypocone was reduced in size, having approximately half the size of the protocone (Fig. 3 E). In 12 other specimens, the hypocone was vestigial or nearly absent (Fig. 3 F). In total, 68 specimens (13.2 %) showed a reduced M 3 hypocone. Additional dental irregularities In addition to the aforementioned dental deviations, some other dental irregularities were observed. Specimen NHMZ- 20382 (G. t. thornicrofti, male, age class E, Zambia) exhibited a diastema between the left P 2 (206) and P 3 (207), which was not present in any of the other studied specimens. Ten specimens showed evidence of broken molars with a smooth surface indicating further use after the breakage (e. g., NAM-NYA- 3, G. g. angolensis, male, age class F, Namibia; NHMZ- 26178, G. g. giraffa, male, age class F, Zimbabwe) (Fig. 3 G). In two female specimens of G. t. tippelskirchi (ZSM- 1911 - 2446, age class F, Tanzania; NHMW- 974, age class G, Kenya) only the right P 4 (108) was lost due to localized malformations or deformations of the maxilla. In addition, three skulls (NHMW- 5575, G. camelopardalis subsp., male, age class G, Sudan; NAM-TAU- 32, G. g. angolensis, male, age class F, Namibia; USNM- 163324, G. r. reticulata, female, age class G, Kenya) showed discoloured molars that likely underlie severe tooth decay (Fig. 3 H). CRANIAL IRREGULARITIES Numerous deviations from the ‘ normal’ cranial anatomy were observed in the dataset. These included maxillary erosions, asymmetrical ossicones, evidence of periosteal growth likely associated with male necking behaviour and / or trauma, congenital malformations, and possible neoplasia. Maxillary erosions The most commonly observed pathology was focal erosions of the maxillary alveolar bone, identified in varying stages across 206 specimens (39.9 % of the total sample). The affected area appeared pitted, and gradually deteriorated, revealing the alveolar cavities and exposed tooth roots. This was more evident on the buccal aspect of the maxilla, but also observed on the lingual aspect, within the alveoli, and also between the alveoli. These erosions typically affected multiple maxillary teeth, however, in some cases only one tooth was affected. In particular, single-tooth erosions were observed in P 2 (106 / 206) (n = 11), P 3 (107) (n = 1), P 4 (108 / 208) (n = 5), M 1 (109 / 209) (n = 31), M 2 (110 / 210) (n = 6), and M 3 (110 / 210) (n = 3) (Fig. 4 A). The erosions were confined to the premolars in some specimens (Fig. 4 B), while in others they were restricted to the molars. Even more frequently, usually in individuals of relatively old age, the erosions were extended and affected most of the teeth (n = 109; 21.1 %). In some specimens of old age this was also linked to extreme dental wear, exposed dental cavities and broken teeth (Fig. 4 C). Finally, there were many specimens that did not retain any teeth. Judging from the morphology of the remaining alveolar surfaces, this may have been caused (at least in part) by bone decay undermining the implantation of the teeth in the maxilla. Ossicone asymmetry Many giraffe skulls showed signs of asymmetry in terms of ossicone size and orientation. Sixteen specimens showed shorter left ossicones, whereas 21 specimens showed shorter right ossicones (Fig. 5 A). Such height difference was also linked to differences in diameter and rugosity. Different shapes of the terminal end of the ossicones were observed, some narrowing towards the tip and not displaying the widening or bulging as seen in most cases. Additionally, four specimens showed signs of bilateral bending of the ossicones, with both facing towards the same direction. However, the same morphology was also seen unilaterally in eleven specimens, in which only one of the ossicones deviated from its standard angle (Fig. 5 B). Potential Trauma Multiple specimens showed signs of non-aggressive periosteal reactive growth which may be related to trauma. Such exostoses were often distributed across areas that may have been impacted by fighting or necking behaviour, i. e. predominantly the ossicone (s), over the dorsal aspect of the orbits, and over the frontal bones. Three specimens (NHMZ- 29112, G. g. giraffa, male, age class G, Botswana; ZSM- 1914 - 1325, G. t. tippelskirchi, male, age class I, Tanzania; ZMB-MAM- 17381, G. t. tippelskirchi, male, age class I, Tanzania; Fig. 6 A, B) also had fenestrations surrounded by severe periosteal reactive bone growth. In addition, multiple specimens showed fractured ossicones with the majority being male (n = 10) versus female (n = 3) (Fig. 6 C, D). One specimen (NHMUK-ZD- 1938.7.8.22, G. c. antiquorum, male, age class F, Cameroon; Fig. 6 E, F) showed distinct signs of trauma, such as erosion and remodification on the left half of the distal part of the skull. Lesions were observed on the temporal bone, the paraoccipital and the mastoid / paracondylar processes, and along the left part of the nuchal crest, ending in an enlarged nuchal hill, which was much larger than that on the right. Secondary ossification was evident on the nuchal crest and the temporal bone. No further pathological evidence were seen on the ossicones or any other part of the cranium. An additional seven specimens showed signs of secondary ossification, periosteal reactions, or lesions in different parts of the skull. Congenital abnormalities Four potential cases of congenital abnormalities were observed in the dataset. A male skull displayed a moderate left lateral deviation of the nasal bones, most consistent with a condition known as campylorrhinus lateralis or wry nose (ZSM- 1914 - 0127, G. t. tippelskirchi, male, age class E; Fig. 7 A, B). Another skull belonged to a male giraffe, recently deceased from natural predation, that had a severe incomplete fusing of the nasal and frontal bones consistent with a midfacial cleft palate (Fig. 7 C-D). The skull exhibited severe damage from predation and local climate, making it unclear whether the defect also extended to the palatine bones of the oral cavity. A noticeable groove over the parietal bones ended between the ossicones, whilst the left ossicone was notably shorter than the right one. Two specimens (RMCA-RG- 25673, G. c. antiquorum, male, age class E, D. R. Congo, Fig. 7 E; NHMW- 5483, Giraffa sp., female, age class D, Schonbrun Zoo, born in Kenya, Fig. 7 F) show bilateral longitudinal fistulae in the nasal bones. In RMCA-RG- 25673 these fistulae were situated near the mesial end of the nasal bones, whereas in NHMW- 5483 they were located more distally, in the middle part of the bone. While present on both sides, they were not perfectly symmetrical in terms of length, width, and position. In the Kordofan specimen the borders of the piercings were faintly covered by secondary bone, whereas in NHMW- 5483 the borders retained the same form as the surrounding bone. These fistulae likely developed congenitally as there was no evidence of healing or bone remodelling to suggest a traumatic origin. However, their origin could not be determined without histological evaluation. Neoplasia One skull showed signs consistent with malignant bone alterations likely indicative of a neoplastic process. NHMZ- 22635 (G. t. thornicrofti, male, adult, Zambia; Fig. 8) had severe bone growth on the right part of the skull from the orbit to the ossicone. The right ossicone was ventrally and laterally deviated from the midline, while its base was noticeably thickened and irregular as compared to the left ossicone. Periosteal reactive growths were evident on the left side, most notably over the left orbit. Still, these changes were more consistent with exostoses resulting from trauma caused by aggression between males. The specimen included the mandible, and the right ramus appeared ‘ moth-eaten’ in some areas. Although suggestive of neoplasia, histopathologic investigation is needed to confirm this diagnosis.	en	Julian, Nikolaos Kargopoulos, Jesús, Julian Fennessy, Anusuya, Jesús Marugán-Lobón, Michael, Anusuya Chinsamy, Stephanie, Michael Brown, Arthur, Stephanie Fennessy, Bernard, Arthur Muneza, Agwanda, Bernard R., Moses, Ogeto Mwebi, Frederick, Moses Otiende, Alice, Frederick Lala, Sven, Alice Petzold, Abdoul, Sven Winter, Moussa, Abdoul Razack, Sara, Moussa Zabeirou, Ferguson, Sara (2026): Craniodental pathologies and irregularities in the giraffe (Giraffa spp.). Zoosystema 48 (19): 590-621, DOI: 10.5252/zoosystema2026v48a19
