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This content will become publicly available on February 1, 2026

Title: Additional analyses of stem catarrhine and hominoid dental morphology support Kapi ramnagarensis as a stem hylobatid
Fossil gibbons are exceedingly rare, with much of the hylobatid fossil record and, consequently, hylobatid evolutionary history remaining unknown. Kapi ramnagarensis was described as a stem hylobatid on the basis of an isolated lower right M3 from ~13.0-12.5 Ma deposits surrounding Ramnagar (J&K), India. This interpretation was recently challenged, with alternative hypotheses suggesting that it is instead a stem catarrhine or a strangely derived pliopithecoid that has converged on hylobatid morphology. A series of morphological features were said to distinguish Kapi from fossil and extant hylobatids; notably, however, none of these features were examined or compared using quantitative analyses. Here, we further examine the dental morphology of Kapi, providing quantitative analyses to critically evaluate the hypothesis that Kapi represents a stem catarrhine or pliopithecoid rather than a stem hylobatid. Results demonstrate that none of the claimed differences between Kapi and hylobatids hold up under closer scrutiny, and multivariate discriminant analyses taking size and shape into account strongly support Kapi as a hylobatid with high posterior probabilities. Although only represented by a single lower molar, Kapi remains the most compelling candidate for the earliest known hylobatid in the fossil record and thus likely documents the simultaneous arrival of lesser and great apes to Asia during the Middle Miocene.  more » « less
Award ID(s):
1945618 1945736
PAR ID:
10618487
Author(s) / Creator(s):
; ; ; ; ; ; ;
Publisher / Repository:
Elsevier
Date Published:
Journal Name:
Journal of Human Evolution
Volume:
199
Issue:
C
ISSN:
0047-2484
Page Range / eLocation ID:
103628
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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