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In this study, we explore the Late Pleistocene (LP) vertebrate faunal diversity in south-eastern Lesser Caucasus based on morphological and genetic identification of fossil bones from Karin Tak cave. For the first time in this under-studied region, we used a bulk bone metabarcoding genetic approach to complement traditional morphology-based taxonomic identifications that are hampered by highly fragmented fossil bones. Excellent ancient DNA (aDNA) preservation allowed for a successful species identification of many bone remains and improved paleoenvironmental interpretations for the region. The aDNA identification of fossil bones revealed a high diversity of animal taxa inhabiting the region between ca. > 42,000 and 25,683–24,803 calibrated years before present (cal. BP).

The human colonisation of New Zealand in the late thirteenth century AD led to catastrophic impacts on the local biota and is among the most compelling examples of human over-exploitation of native fauna, including megafauna. Nearly half of the species in New Zealand' s pre-human avifauna are now extinct, including all nine species of large, flightless moa (Aves: Dinornithiformes). The abundance of moa in early archaeological sites demonstrates the significance of these megaherbivores in the diet of the first New Zealanders. Combining moa assemblage data, based on DNA identification of eggshell and bone, with morphological identification of bone (literature and museum catalogued specimens), we present the most comprehensive audit of moa to date from several significant 13th-15th century AD archaeological deposits across the east coast of the South Island. Mitochondrial DNA (mtDNA) was amplified from 251 of 323 (78%) eggshell fragments and 22 of 27 (88%) bone samples, and the analyses revealed the presence of four moa species: Anomalopteryx didiformis; Dinornis robustus; Emeus crassus and Euryapteryx curtus. The mtDNA, along with polymorphic microsatellite markers, enabled an estimate of the minimum number of individual eggs consumed at each site. Remarkably, in one deposit over 50 individual eggs were identified - a number that likely represents a considerable proportion of the total reproductive output of moa in the area and emphasises that human predation of all life stages of moa was intense. Molecular sexing was conducted on bones (n = 11). Contrary to previous ancient DNA studies from natural sites that consistently report an excess of female moa, we observed an excess of males (2.7:1), suggestive that males were preferential targets. This could be related to different behaviour between the two highly size-dimorphic sexes in moa. Lastly, we investigated the moa species from recovered skeletal and eggshell remains from seven Wairau Bar burials, and identified the presence of only the larger species of moa, E. curtus and D. robustus.

Ancient DNA was isolated from the bones of 267 individuals of the extinct New Zealand moa (Aves: Dinornithiformes) from two late Holocene deposits [Pyramid Valley (PV) and Bell Hill Vineyard (BHV)] located 5.7 km apart in North Canterbury, South Island. The two sites' combined fossil record cover the last 3000 years of pre-human New Zealand and mitochondrial DNA confirmed that four species (Dinornis robustus, Euryapteryx curtus, Emeus crassus, and Pachyornis elephantopus) were sympatric in the region. However, the relative species compositions in the two deposits differed significantly with D. robustus and E. crassus being most abundant at PV while E. curtus outnumbered the other three moa taxa combined at BHV. A subsample of 227 individuals had sufficient nuclear DNA preservation to warrant the use of molecular sexing techniques, and the analyses uncovered a remarkable excess of females in both deposits with an overall male to female ratio of 1:5.1. Among juveniles of E. curtus, the only species which was represented by a substantial fraction of juveniles, the sex ratio was not skewed (10 ♂, 10 ♀), suggesting that the observed imbalance arose as a result of differential mortality during maturation. Surprisingly, sex ratios proved significantly different between sites with a 1:2.2 ratio at BHV (n = 90) and 1:14.2 at PV (n = 137). Given the mobility of large ratites, and the proximity of the two fossil assemblages in space and time, these differences in taxonomic and gender composition indicate that moa biology and the local environment have affected the fossil representation dramatically and several possible explanations are offered. Apart from adding to our understanding of moa biology, these discoveries reinforce the need for caution when basing interpretation of the fossil record on material from a single site.