Plio-Pleistocene transition. The dating is primarily based on biostratigraphical correlation of lower marine fauna and a few fragments of terrestrial mammals. Although deposited in marine and coastal environments, the sediments contain abundant remains of terrestrial and limnic organisms. This paper examines macroscopic plant and insect remains. About 60 taxa of vascular plants and 120 insect taxa have so far been identified. Nearly all of the named insect species are extant, extralimital forms, generally of a recent subarctic/boreal and more or less circumpolar distribution. The species composition shows that upland areas were covered with forest-tundra and heathland and that mesotrophic, well-vegetated lakes and a number of other wetland localities existed in the area. The presence of arctic plants in the formation puts some time constraints on their origin.

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Terraces of different age in the Zackenberg delta, located at 74°N in northeast Greenland, have provided the opportunity for an interdisciplinary approach to the investigation of Holocene glacial, periglacial, pedological, biological and archaeological conditions that existed during and after delta deposition.The raised Zackenberg delta accumulated mainly during the Holocene Climatic Optimum, starting slightly prior to 9500 cal. yr BP (30 m a.s.l.) and continued until at least 6300 cal. yr BP (0.5 m a.s.l.). Evidence of sea-level change is based on conventional 14 C dates of shells from the marine delta bottomsets, 14 C AMS dating of macroscopic plant material from the foresets and of fluvial deposits. Arthropod and plant remains from 7960 cal. yr BP in the delta foresets include the oldest evidence of the arctic hare in Greenland and evidence of a rich herb flora slightly different from the modern flora. Empetrum nigrum and Salix herbacea remains indicate a summer temperature at least as high as today during delta deposition. Post-depositional nivation activity, dated by luminescence, lichenometry and Schmidt Hammer measurements indicate mainly late Holocene activity, at least since 2900 yr BP, including Little Ice Age (LIA) avalanche activity. Pedological analyses of fossil podsols in the Zackenberg delta, including 14 C AMS dating of selected organic rich B-horizons, show continued podsol development during the Holocene Climatic Optimum and into the subsequent colder period of the late Holocene, until 3000-2400 yr BP. A Neo-Eskimo house ruin found on the lower part of the delta, presently being eroded by the sea, is dated to AD 1800. It presumably was abandoned prior to AD 1869, and suggests that some of the last Eskimos that lived in northeast Greenland might have occupied the Zackenberg delta.

Marine Quaternary deposits, here named the Store Koldewey Formation, are found at $120 m above sea level in northeast Greenland (761N). The sequence is referred to the Olduvai normal polarity subchron at 1.95-1.78 Ma BP based on palaeomagnetic studies (palaeomagnetically reversed), amino acid epimerization ratios and evidence from marine and non-marine fossils. The sediments and the fauna show that the sequence was deposited on a mid or inner shelf, and some elements of the marine mollusc and foraminiferal assemblages indicate water temperatures between À1 and 111C and seasonal sea ice cover during deposition. Mean summer air temperatures were around 61C higher than at present, as demonstrated by the occurrence of southern extralimital terrestrial species. Wellpreserved remains of land plants indicate that the adjacent land area was dominated by sub-arctic forest-tundra with the trees Larix and Betula, shrubs, herbs and mosses. Most of the species represented as fossils have recent circumpolar geographical ranges. An extinct brachiopod species and an extinct gastropod species have been found, but the other macrofossils are referred to extant species. The brachiopod is erected as a new genus and species, Laugekochiana groenlandica.

Macrofossil plant and insect remains from nearshore marine sediments in Jameson Land, central East Greenland show that the land biotas of the last interglacial stage, the Langelandselv stage, were more diverse than those of the Holocene. Rich dwarf shrub heaths with a diverse assemblage of ericaceous plants occupied low land areas with copses of Betula pubescens on sheltered sites. Many southern extra‐limital species were present, and the mean summer temperature was c. 5°C higher than today. The subarctic bioclimatic zone was displaced from southernmost Greenland/Iceland to central East Greenland. The diverse beetle fauna was of palaearctic affinity and strikingly different from the Plio‐Pleistocene and the Holocene Greenlandic beetle faunas. A few fossil assemblages from the Hugin Sø Interstade, which is correlated with oxygen isotope stage 5c (early last glacial stage), point to poor, perhaps entirely herbaceous vegetation with a mean summer temperature that was perhaps 3 4°C lower than today.