Abstract
This study describes two new sacral specimens of Nacholapithecus kerioi, KNM-BG 42753I and KNM-BG 47687A, from the Aka Aiteputh Formation in Nachola, northern Kenya, excavated in 2002. They are of roughly equal size and are considered to belong to males. When scaled by body mass, the lumbosacral articular surface area of the better preserved specimen, KNM-BG 42753I, is smaller than that in Old World monkeys but similar to that in extant great apes and New World monkeys, as well as Proconsul nyanzae. The relatively narrow dimensions of the first sacral vertebral body in the transverse and sagittal planes are characteristics of N. kerioi and P. nyanzae and similar to those of extant great apes. In N. kerioi, lumbosacral surface area relative to body mass is small. This may simply be an extension of a trend from the previously reported small thoracolumbar vertebrae to the sacrum. The first sacral vertebrae of N. kerioi and Epipliopithecus vindobonensis have a higher craniocaudal vertebral body reduction (CVR; a higher CVR indicates a wider cranial width relative to a narrower caudal width), similar to that in Old World monkeys. Old World monkeys have a higher CVR, and usually have three sacral vertebrae, fewer than seen in extant great apes, which have a lower CVR and four to six (sometimes as many as eight) sacral vertebrae. New World monkeys have a lower CVR than Old World monkeys, but generally possess only three sacral vertebrae, and have a large caudal articular surface, which may be related, at least in the Atelidae, to the grasping ability of their tails. The possibility that N. kerioi had only three sacral vertebrae cannot be ruled out, because E. vindobonensis and Old World monkeys, with higher CVRs, have sacra consisting of three sacral vertebrae.
| Original language | English |
|---|---|
| Pages (from-to) | 117-125 |
| Number of pages | 9 |
| Journal | Journal of Human Evolution |
| Volume | 94 |
| DOIs | |
| Publication status | Published - 2016 May 1 |
Fingerprint
Keywords
- Ape
- Epipliopithecus
- Fossil
- Proconsul
- Vertebra
ASJC Scopus subject areas
- Ecology, Evolution, Behavior and Systematics
- Arts and Humanities (miscellaneous)
- Education
Cite this
Sacral vertebral remains of the Middle Miocene hominoid Nacholapithecus kerioi from northern Kenya. / Kikuchi, Yasuhiro; Nakatsukasa, Masato; Nakano, Yoshihiko; Kunimatsu, Yutaka; Shimizu, Daisuke; Ogihara, Naomichi; Tsujikawa, Hiroshi; Takano, Tomo; Ishida, Hidemi.
In: Journal of Human Evolution, Vol. 94, 01.05.2016, p. 117-125.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Sacral vertebral remains of the Middle Miocene hominoid Nacholapithecus kerioi from northern Kenya
AU - Kikuchi, Yasuhiro
AU - Nakatsukasa, Masato
AU - Nakano, Yoshihiko
AU - Kunimatsu, Yutaka
AU - Shimizu, Daisuke
AU - Ogihara, Naomichi
AU - Tsujikawa, Hiroshi
AU - Takano, Tomo
AU - Ishida, Hidemi
PY - 2016/5/1
Y1 - 2016/5/1
N2 - This study describes two new sacral specimens of Nacholapithecus kerioi, KNM-BG 42753I and KNM-BG 47687A, from the Aka Aiteputh Formation in Nachola, northern Kenya, excavated in 2002. They are of roughly equal size and are considered to belong to males. When scaled by body mass, the lumbosacral articular surface area of the better preserved specimen, KNM-BG 42753I, is smaller than that in Old World monkeys but similar to that in extant great apes and New World monkeys, as well as Proconsul nyanzae. The relatively narrow dimensions of the first sacral vertebral body in the transverse and sagittal planes are characteristics of N. kerioi and P. nyanzae and similar to those of extant great apes. In N. kerioi, lumbosacral surface area relative to body mass is small. This may simply be an extension of a trend from the previously reported small thoracolumbar vertebrae to the sacrum. The first sacral vertebrae of N. kerioi and Epipliopithecus vindobonensis have a higher craniocaudal vertebral body reduction (CVR; a higher CVR indicates a wider cranial width relative to a narrower caudal width), similar to that in Old World monkeys. Old World monkeys have a higher CVR, and usually have three sacral vertebrae, fewer than seen in extant great apes, which have a lower CVR and four to six (sometimes as many as eight) sacral vertebrae. New World monkeys have a lower CVR than Old World monkeys, but generally possess only three sacral vertebrae, and have a large caudal articular surface, which may be related, at least in the Atelidae, to the grasping ability of their tails. The possibility that N. kerioi had only three sacral vertebrae cannot be ruled out, because E. vindobonensis and Old World monkeys, with higher CVRs, have sacra consisting of three sacral vertebrae.
AB - This study describes two new sacral specimens of Nacholapithecus kerioi, KNM-BG 42753I and KNM-BG 47687A, from the Aka Aiteputh Formation in Nachola, northern Kenya, excavated in 2002. They are of roughly equal size and are considered to belong to males. When scaled by body mass, the lumbosacral articular surface area of the better preserved specimen, KNM-BG 42753I, is smaller than that in Old World monkeys but similar to that in extant great apes and New World monkeys, as well as Proconsul nyanzae. The relatively narrow dimensions of the first sacral vertebral body in the transverse and sagittal planes are characteristics of N. kerioi and P. nyanzae and similar to those of extant great apes. In N. kerioi, lumbosacral surface area relative to body mass is small. This may simply be an extension of a trend from the previously reported small thoracolumbar vertebrae to the sacrum. The first sacral vertebrae of N. kerioi and Epipliopithecus vindobonensis have a higher craniocaudal vertebral body reduction (CVR; a higher CVR indicates a wider cranial width relative to a narrower caudal width), similar to that in Old World monkeys. Old World monkeys have a higher CVR, and usually have three sacral vertebrae, fewer than seen in extant great apes, which have a lower CVR and four to six (sometimes as many as eight) sacral vertebrae. New World monkeys have a lower CVR than Old World monkeys, but generally possess only three sacral vertebrae, and have a large caudal articular surface, which may be related, at least in the Atelidae, to the grasping ability of their tails. The possibility that N. kerioi had only three sacral vertebrae cannot be ruled out, because E. vindobonensis and Old World monkeys, with higher CVRs, have sacra consisting of three sacral vertebrae.
KW - Ape
KW - Epipliopithecus
KW - Fossil
KW - Proconsul
KW - Vertebra
UR - http://www.scopus.com/inward/record.url?scp=84964562271&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84964562271&partnerID=8YFLogxK
U2 - 10.1016/j.jhevol.2016.03.006
DO - 10.1016/j.jhevol.2016.03.006
M3 - Article
C2 - 27178463
AN - SCOPUS:84964562271
VL - 94
SP - 117
EP - 125
JO - Journal of Human Evolution
JF - Journal of Human Evolution
SN - 0047-2484
ER -