Human burials at the Kisese II rockshelter, Tanzania

Abstract

Objectives: The Late Pleistocene and early Holocene in eastern Africa are associated with complex evolutionary and demographic processes that contributed to the population variability observed in the region today. However, there are relatively few human skeletal remains from this time period. Here we describe six individuals from the Kisese II rockshelter in Tanzania that were excavated in 1956, present a radiocarbon date for one of the individuals, and compare craniodental morphological diversity among eastern African populations.

Materials and methods: This study used standard biometric analyses to assess the age, sex, and stature of the Kisese II individuals. Eastern African craniodental morphological variation was assessed using measures of dental size and a subset of Howells' cranial measurements for the Kisese II individuals as well as early Holocene, early pastoralist, Pastoral Neolithic, and modern African individuals.

Results: Our results suggest a minimum of six individuals from the Kisese II collections with two adults and four juveniles. While the dating for most of the burials is uncertain, one individual is directly radiocarbon dated to ~7.1 ka indicating that at least one burial is early Holocene in age. Craniodental metric comparisons indicate that the Kisese II individuals extend the amount of human morphological diversity among Holocene eastern Africans.

Conclusions: Our findings contribute to a growing body of evidence that Late Pleistocene and early Holocene eastern Africans exhibited relatively high amounts of morphological diversity. However, the Kisese II individuals suggest morphological similarity at localized sites potentially supporting increased regionalization during the early Holocene.

Keywords: early Holocene; eastern Africa; morphological variation.

FIGURE 1

Map and Inskeep photos (a) a map of eastern Africa with the location of Kisese II. (b) Kisese II in 2018, and (c) the area approximately corresponding with the area shown in (d–g); photos by Samantha Porter. Photos (d–f) are of Inskeep's excavation of “burial III/IV” and show at least two individuals in spit VII. Ostrich eggshell C¹⁴ dates obtained from spit VII suggest two calibrated age ranges that provide minimum age estimates: 12.87–12.15 and 42.79–41.73 ka. The cranium on the right shows fracture patterns and partially‐healed cranial trauma that matches juvenile KNM‐KX 9 (Figure S3). Notes associated with the skeletal material suggest KNM‐KX 1 is also shown in the burial III/IV photo, although the fracture patterns on the ossa coxae visible in the photographs do not precisely match KNM‐KX 1. (g) Inskeep's photos show one other burial labeled “burial 2” that contains an older juvenile or adult buried on their side

FIGURE 2

Cranial remains of KNM‐KX 1. The cranium is shown in (a) anterior, (b) posterior, (c) superior, (d) inferior, (e) left lateral, and (f) right lateral views. The mandible is shown in (g) superior and (h) inferior views. Left (i and j) and right (m and n) zygomatic fragments, with some frontal and maxilla, are shown in anterior and posterior views. Right (k) and left (l) maxillary fragments are shown in lateral view. Right (o) and left (p) scapulae are shown in posterior view. The left (q and r) and right (s and t) ossa coxae are shown in medial and laterial views. The maxillae, scapula, and ossa coxae are not numbered

FIGURE 3

Cranial remains associated with KNM‐KX 2. The cranium is shown in (a) anterior, (b) posterior, (c) superior, (d) inferior, (e) left lateral, and (f) right lateral views. The mandible is shown in (g) superior, (h) inferior, (i) left lateral, and (j) right lateral views. The right and left ossa coxae are shown in (k and m) medial and (l and n) lateral views. The mandible and ossa coxae are not numbered

FIGURE 4

Cranial and dental metric comparisons. Boxplots showing mandibular (a) and maxillary (b) buccolingual widths. Boxplots of the ratio of maximum cranial breadth to length (c) and nasal breadth to length (d). Boxplots showing the ratios maximum cranial breadth to length (e) and nasal breadth to length (f) in the early Holocene later stone age (LSA) and pastoral Neolithic samples. For all plots, the upper and lower bound of the boxes corresponds with the 25th and 75th percentiles and the whiskers extend 1.5 times the interquartile range in either direction. The median is represented by a horizontal line inside the boxes