National Museums Scotland

Abstract Leading biomedical resources rely on genome variation in Britain 1–3 , but the historical processes that shaped present-day fine-scale diversity remain debated 4–13 . Here we sequenced 1039 ancient shotgun genomes from Britain (median 1.4-fold coverage), primarily dating to the first millennium CE. We imputed ∼660 million variants in the UK Biobank 14–16 and employed genealogy-based ancestry reconstruction. We found an association between Iron Age consanguinity and matrilineal burial practices 17 , later disrupted following the Roman Conquest. Despite this societal impact, only 20% of Roman-period individuals carried detectable ancestry from outside Britain. In contrast, from the 6th century CE we detect widespread influx of ancestry in over 70% of individuals in southern’Anglo-Saxon’ Britain, with limited local admixture. We find previously underappreciated heterogeneity, with ancestries associated with Central and Southern Europe rising in prevalence from the 7th century CE. We demonstrate distinct Scandinavian-related ancestry in many Viking-associated contexts, but show that the population-level impact of the Viking Age in Britain was limited. Finally, we detect pre-medieval selection on variants linked with key immunity genes TLR10-TLR1 and IRF8 . These results identify population-level and selective processes that shape variation and disease risk in Britain today.

About 900 specific fig-fig wasp interactions are distributed throughout tropical ecosystems. Despite this ubiquity, floral mimicry of figs (inflorescences of Ficus spp.; Moraceae) has never been observed. Recently, we found a bizarre Apocynaceae, Heterostemma ficoides, bearing globose closed flowers that look similar to figs and are visited by a Kradibia wasp, the pollinator of Ficus heterophylla. Does the flower of H. ficoides mimic the fig to achieve its pollination success? We investigated floral visitors and their activities on H. ficoides flowers, compared chemical and physical cues between these flowers and F. heterophylla figs, then tested the attraction of the Kradibia wasps to floral volatiles of H. ficoides. Heterostemma ficoides flowers were visited by a community of Diptera and Hymenoptera, some of which breed in F. heterophylla figs. Pollination was mainly achieved by a Megaselia fly and secondarily by the Kradibia wasp. Floral volatiles of H. ficoides resembled those of F. heterophylla figs and attracted the Kradibia wasp. While the fly completed its cycle on H. ficoides flowers, the fig wasp could not. This system represents an unprecedented combination of two pollination modes and constitutes the first example in which a brood-site mutualism operates simultaneously with brood-site deception.

Abstract Dinosaur fossils from the Isle of Skye (Scotland, UK), particularly the abundant trace fossil record, provide a window into dinosaur evolution during the poorly known Middle Jurassic. Here we present a comprehensive description of the Duntulm tracksite from Cairidh Ghlumaig Bay, using aerial photography to provide whole site maps, catalogue the tracks, and identify trackways. The tracksite is located in rocks deposited in a shallow lagoonal environment and is dominated by small‐ to medium‐sized (<75 cm) sauropod footprints spanning several preservation styles, from casts with details of toes to impressions with less distinct features. Several short, narrow‐gauge trackways indicate that the sauropods were moving with a walking gait and the wide range of orientations of the trackways does not indicate any gregarious behaviour. Sparse, isolated theropod footprints are also present along the Duntulm coastline. The abundance of sauropod footprints at this locality prompts an examination of the substrate preferences of Skye's dinosaurs. We surveyed all currently known dinosaur tracks from the island and statistically analysed the relationship of trackmaker with substrate. This analysis indicates that Skye's sauropods had a preference for lagoonal substrates whereas ‘non‐sauropod’ dinosaurs (theropods, thyreophorans and ornithopods) are more abundant in subaerially exposed mudflats. We argue that this signal is robust, but this pattern can be further tested as more footprints are discovered on Skye.

Phenotypic changes in mammals, often observed following domestication, affect both pelage and skeletal structures. Our study focuses on morphological changes in a key skeletal element of the ungulate locomotor system-the metacarpal-following altered habitat and living status due to human management. We used three-dimensional geometric morphometrics to examine morphological variations in metacarpals within a primitive domestic sheep breed-Soay sheep (Ovis aries)-of which some populations experienced a translocation from a feral state on the mountainous island of St Kilda to living under closely managed conditions on flat paddocks in England. We first quantified the effects of sex and ontogeny on metacarpal morphology in the feral St Kilda population, establishing a baseline against which the variation in the managed English population was then evaluated. Our results reveal a phenotypic response in the translocated sheep, for which a plastic response in locomotor behaviour to the changed physical environment provides the most plausible explanation. Nevertheless, further tests integrating genetic analysis are still needed to clarify the genomic underpinnings of the observed variation. Our findings highlight the potential of bone morphology to trace the domestication process and reconstruct past human-animal-environment interactions in zooarchaeological contexts.