No abstract

DNA was extracted from the remains of 35 ground sloths from various parts of North and South America. Two specimens of Mylodon darwinii, a species that went extinct at the end of the last glaciation, yielded amplifiable DNA. However, of the total DNA extracted, only -1/1000 originated from the sloth, whereas a substantial part of the remainder was of bacterial and fungal origin. In spite of this, >1100 bp of sloth mitochondrial rDNA sequences could be reconstructed from short amplification products. Phylogenetic analyses using homologous sequences from all extant edentate groups suggest that Mylodon darwinii was more closely related to the two-toed than the three-toed sloths and, thus, that an arboreal life-style has evolved at least twice among sloths. The divergence of Mylodon and the two-toed sloth furthermore allows a date for the radiation of armadillos, anteaters, and sloths to be estimated. This result shows that the edentates differ from other mammalian orders in that they contain lineages that diverged before the end of the Cretaceous Period.

A series of distinctive mammalian assemblages spanning much of the British Late Pleistocene is defined on the basis of type localities and a formal biozonation proposed. The Joint Mitnor Cave mammal assemblage-zone includes the famous ''Hippopotamus fauna'' of the early part of the Last Interglacial complex (Oxygen Isotope Substage 5e). This is succeeded by the Bacon Hole mammal assemblage-zone in which hippopotamus is no longer present and species like mammoth, roe deer and northern vole re-enter the British region. This assemblage-zone appears to represent the later substages of OIS 5. A faunal grouping dominated by bison and reindeer is named the Banwell Bone Cave mammal assemblage-zone and is believed to correlate closely with the Early Devensian (OIS 4). The Pin Hole mammal assemblage-zone includes the familiar mammoth-steppe faunas of the Middle Devensian (OIS 3) dominated by horse, woolly rhinoceros and mammoth. The Lateglacial Interstadial is characterized by the Gough's Cave mammal assemblage-zone in which horse, red deer and humans are well represented (part of OIS 2). No definitive evidence for human activity can be found for a period spanning the Last Interglacial complex (OIS 5) and the Early Devensian (OIS 4). Human populations return to Britain with the Pin Hole mammal assemblage-zone fauna during the Middle Devensian (OIS 3) and reappear after the Dimlington Stadial during the Late Devensian (OIS 2) but in a different faunal association. r

The acheulian site at Boxgrove contains one of the most extensive areas of in situ fauna and flintwork yet discovered in Britain. This material is found in a complex sequence of sediments which represent depositional conditions from a 42 m sea level rise to the onset of a full periglacial climate. Excavation of the archaeological horizon has been accompanied by a programme of multidisciplinary research examining site formation processes, palaeolandscape and palaeoecological development, using sedimentological and environmental reconstruction techniques. Dating of the site is tentative as no absolute dates are available at present. However, comparative analysis with other British sites would suggest a position for the Boxgrove sequence within the Middle Pleistocene. The archaeological horizon is interpreted as being deposited towards the latter part of an interglacial or an interstadial period.

In December 1998, we presented a Special section on great finds and publications of 1848. The discovery of the Gibraltar skull was in that famous year. Now, 150 years later new excavations and a recent conference have once again focused interest on this, the first place where Neanderthal remains were found.