Plainware ceramics from Sāmoa: Insights into ceramic chronology,cultural transmission,and selection among colonizing populations

The first people in Sāmoa produced a varied ceramic archaeological record including a single deposit with decorated Lapita ceramics on the island of ‘Upolu in the west of the archipelago and a nearly contemporaneous plainware deposit over 250 km to the east on Ofu Island. Post-Lapita ceramic change across Sāmoa is similar with almost no decoration, local ceramic production, limited vessel form diversity, and changing frequencies of thin- and thick-wares. This Sāmoan ceramic record is different from nearby Tonga and Fiji where early decorated Lapita ceramics are widely distributed, there are no thickness-defined ware types, and for Fiji, post-Lapita ceramics are more variable. Here we investigate the apparent uniqueness of the Sāmoan ceramic record through an analysis of early plainware ceramics, the second oldest after the Ofu deposits, from Tutuila Island in the center of the Sāmoan archipelago. Our assemblage-specific findings are similar to other Sāmoan plainware analyses, but we suggest the ceramic and other archaeological evidence from Sāmoa and the region indicates Sāmoa was colonized by a few isolated groups and that within the context of cultural transmission of ceramic variants, selection explains thickness variation and likely other aspects of Sāmoan ceramic change.     

A radiocarbon chronology for Sāmoan prehistory

The corpus of radiocarbon dates for Sāmoan archaeology has grown exponentially since the pioneering work of Green and Davidson in the 1960s, enabling us to re-analyze the archipelago's cultural chronology. A reliable and valid radiocarbon chronology forms the basis for describing and explaining cultural variability and change in the central Pacific. Towards that end, in this paper we compile the available radiocarbon dates from published and unpublished (“grey literature”) sources. We critically evaluate 236 radiocarbon dates following a chronometric hygiene protocol to identify the most secure and reliable age estimates. We accept 147 dates (62.3%) as a means of addressing two significant issues for Sāmoan prehistory: (1) the chronology of settlement and human expansion across the archipelago pre-2000 cal BP, which relates to issues of Lapita colonization, and the effect of island geomorphology on settlement; and (2) analysis of the so-called “Dark Ages” (ca. 1500–1000 cal BP), a period relevant to issues of social complexity and East Polynesian settlement. Our research highlights the need for a rigorous sampling protocol for radiocarbon dating.     

The architecture of cancellous bone in the hindlimb of moa (Aves: Dinornithiformes), with implications for stance and gait

Bishop, P.J., Scofield, R.P. & Hocknull, S.A. 6 May 2019. The architecture of cancellous bone in the hindlimb of moa (Aves: Dinornithiformes), with implications for stance and gait.. The architecture of cancellous bone in the hindlimb of moa (Aves: Dinornithiformes), with implications for stance and gait. Alcheringa XXX, X–X. ISSN 0311-5518.0311-5518.

P.J. Bishop* [pbishop@rvc.ac.uk], Structure and Motion Laboratory, Department of Comparative Biomedical Sciences, Royal Veterinary College, Hawkshead Lane, Hatfield AL9 7TA, UK; R.P. Scofield? [pscofield@canterburymuseum.com], Canterbury Museum, Rolleston Avenue, Christchurch 8013, New Zealand; S.A. Hocknull? [scott.hocknull@qm.qld.gov.au], Geosciences Program, Queensland Museum, 122 Gerler Road, Hendra, Queensland 4011, Australia. *Also affiliated with: Geosciences Program, Queensland Museum, 122 Gerler Road, Hendra, Queensland 4011, Australia. ?Also affiliated with: Department of Geological Sciences, University of Canterbury, Christchurch 8140, New Zealand. ?Also affiliated with: School of Biosciences, University of Melbourne, Royal Parade, Parkville, Victoria 3052, Australia.

The extinct, flightless moa of New Zealand included some of the largest birds to have existed and possessed many distinguishing pelvic and hindlimb osteological features. These features may have influenced stance and gait in moa compared with extant birds. One means of assessing locomotor biomechanics, particularly for extinct species, is quantitative analysis of the architecture of cancellous bone, since this architecture is adapted to suit its mechanical environment with high sensitivity. This study investigated the three-dimensional architecture of cancellous bone in the femur, tibiotarsus and fibula of three moa species: Dinornis robustus, Pachyornis elephantopus and Megalapteryx didinus. Using computed tomographic X-ray scanning and previously developed fabric analysis techniques, the spatial variation in cancellous bone fabric patterns in moa was found to be largely comparable with that previously reported for extant birds, particularly large species. Moa hence likely used postures and kinematics similar to those employed by large extant bird species, but this interpretation is tentative on account of relatively small sample sizes. A point of major difference between moa and extant birds concerns the diaphyses; cancellous bone invades the medullary cavity in both groups, but the invasion is far more extensive in moa. Combined with previous assessments of cortical geometry, this further paints a picture of at least some moa species possessing very robust limb bones, for which a convincing explanation remains to be determined