James H. Dickson

Partitioning and diversity of nuclear and organelle markers in native and introduced populations of Epipactis helleborine (Orchidaceae)

Variability of allozymes (1170 individuals, 47 populations) and chloroplast DNA (692 individuals, 29 populations) was examined in native European and introduced North American populations of Epipactis helleborine (Orchidaceae). At the species level, the percentage of allozyme loci that were polymorphic (P(99)) was 67%, with a mean of 2.11 alleles (A) per locus, and an expected heterozygosity (H(exp)) of 0.294. At the population level, mean P(99) = 56%, mean A = 1.81, and mean H(exp) = 0.231. Although field observations suggest that self-pollination occurs frequently, populations had a genetic structure consistent with Hardy-Weinberg expectations and random mating (mean F(IS) = 0.002). There was significant deviation from panmixia associated with population differentiation (mean F(ST) = 0.206). The distribution of two chloroplast haplotypes showed that 15 of the 29 populations were polymorphic. Using both nuclear and organelle F(ST) estimates, a pollen to seed flow ratio of 1.43 : 1 was calculated. This is very low compared with published estimates for other plant groups, consistent with the high dispersability of orchid seeds. Finally, there was no evidence for a genetic bottleneck associated with the introduction of E. helleborine to North America.

Evidence concerning the roman military diet at Bearsden, Scotland, in the 2nd Century AD

Abstract Analyses of sterols and biological studies have shown that a Roman defensive ditch was also a cesspit. The plant debris includes wheat fragments dispersed from defecated bread or other farinaceous food. These techniques may reveal ancient diets in a detail previously impossible to achieve.

MIDDLE MIDLANDIAN FRESHWATER SERIES AT DERRYVREE, MAGUIRESBRIDGE, COUNTY FERMANAGH, NORTHERN IRELAND

During February and March 1969 road excavations in Derryvree townland (H 361390),§ Co. Fermanagh, cut obliquely through a north-east to south-west trending drumlin 2 km north-east of Maguiresbridge (figure 1). The excavations revealed a freshwater deposit of silts and fine sands between two thick and distinct till sheets which formed the drumlin. The organic silts and fine sands contained a flora and fauna of full glacial aspect, which have given a 14C date of 30 500+1170-1030 years B.P. (Birm.166). The flora and fauna indicate that open tundra vegetation and a periglacial climatic régime prevailed in the area at this time.

Flora, fauna and climate of Scotland during the Weichselian Middle Pleniglacial ^ palynological, macrofossil and coleopteran investigations

Thin lenses of organic-rich material, on the upper surface of a layer of glacio-fluvial deposits have been studied in an open cast coal-mine near Sourlie, western Scotland. Radiocarbon dates on antler fragments, plant debris and bulk organic matter from silt, showed that the sediments accumulated between ca. 33 500 and 29 000 14C yr BP, during a period when this part of western Scotland was free of glaciers. The organic-rich sediments yielded a very rich flora and fauna and in total about 160 plant taxa and 61 coleopteran taxa were recorded together with other invertebrates. The Sourlie flora is one of the richest late Middle Weichselian floras yet studied within the British Isles. Leg bones of Coelodonta antiquitatis (woolly rhinoceros) and Rangifer tarandus (reindeer) were also found at the site. During this period, the landscape was treeless and the vegetation could be characterised as an intermediate between a low shrub tundra and sedge–grass–moss tundra. Both the flora and arthropod fauna suggest that during formation of the organic-rich layers at Sourlie, mean July temperatures were 9–10°C. The flora suggests also that at the beginning of formation of these layers, minimum mean July temperatures increased from 7 to 9–10°C, but later dropped again to 7–8°C. A possible time correlation with one of the warmer periods of the Dansgaard–Oeschger cycles in the stable oxygen isotope record of the Greenland ice cores during this period is proposed. The arthropod fauna suggests that mean January temperatures were somewhere between −34 and −11°C. Mean annual temperatures lay probably between −1 and −10°C, which implies the possible presence of discontinuous or continuous permafrost in the area. During winter, a protective snow cover of varying thickness probably enabled perennial plants, especially shrubs, to survive.

Kwäday Dän Ts'ìnchì, the first ancient body of a man from a North American glacier: reconstructing his last days by intestinal and biomolecular analyses

We report on scientific analyses of the only well-preserved ancient human body ever recovered from a North American glacier. The body was found high in the mountains of northwest British Columbia at about 80 km from the nearest point of the strongly indented coast of southern Alaska. The geographical location suggests that the young man, aged about 20 years, could have lived either on the mild coast or in the continental interior. Preliminary environmental scanning electron microscopy (ESEM) and light microscope studies of the contents of the digestive tract reveal pollen of an intertidal salt-marsh plant and pieces of a marine crustacean. Remains of coastal zone plants (a fruit of a flowering plant and a needle of a coniferous tree) had adhered to the deceaseds robe. Stable isotope analyses of bone and muscle show that more than 90% of the dietary protein was from marine sources. We conclude that this individual had strong coastal connections during his life and had been on the coast shortly before he died about 550 to 600 years ago.

The fauna, flora and palaeoenvironmental significance of deposits beneath the low terrace of the River Great Ouse at Radwell, Bedfordshire, England

Pits in the lowest terrace of the Great Ouse near the village of the Radwell, Bedfordshire exposed sections in sand and gravel together with channel fills of organic mud. This fill contains remains of molluscs, ostracods, insects and plant macro-fossils. Interpretation of the remains suggest environmental change under interstadial conditions, probably in the Mid-Devensian sub-stage. Problems of interpreting local and regional environments from faunal and fossil indicators contained within fluviatile deposits are discussed.

Mosses and the Tyrolean Iceman's Southern Provenance

The Tyrolean Iceman’s clothes have yielded remains of a total of 30 different bryophytes (mosses and liverworts), at least nine of which could not have grown at the great altitude of the death site. Most crucial are the two low altitude woodland mosses Neckera complanata and N. crispa. Their distribution patterns in Tyrol indicate strongly that the Iceman came from the south (modern Italy) rather than the north (Austria).

Scottish woodlands: Their ancient past and precarious present

Summary The highly complex history of Pinus sylvestris in Scotland is outlined and new radiocarbon ages for stumps in west central Scotland are published. What Roman and later authors meant by the Great Wood of Caledon is critically appraised. Contrary to the long held and often repeated belief, the Romans marched into a lowland Scotland already largely cleared of woodland. There are oak woodlands in Scotland, such as Mugdock and Garscadden Woods, that show very clear signs of ancient woodmanship, as discussed for England by Rackham. Enthusiasts for the reconstruction of the wildwood in Scotland face a very difficult task; they need to take account of period, place and plants other than trees.

Epilogue: The search for explanations and future developments

In the initial phase of research into the Iceman, four hypotheses — the hunter, shaman, metal prospector and shepherd theories — were proposed to explain the find in its entirety (Egg et al., 1993). On the basis of the detailed scientific investigations conducted in the meantime, however, the assumption that the Iceman was in some way involved in an early form of transhumance has now gained general acceptance.

Vegetational history of central Scotland

Summary The vegetation history of central Scotland has been summarized from information obtained primarily from pollen analysed sites in the region. Open ground taxa began to be replaced by a dwarf shrub community during the late-glacial period but this process was reversed by the Loch Lomond glacial readvance. Following this cold period dwarf shrubs again migrated into the area. These were gradually followed by the major tree taxa until, by the time of maximum woodland expansion, central Scotland was covered by mixed deciduous woodland with small amounts of Scots pine growing on drier areas of peat bog. The expansion of the human population led to increasing woodland clearance and by the Iron Age extensive clearance of the woodlands of central Scotland was underway. Over the last 2000 yr changes in population have resulted in corresponding changes in the wood-land cover of central Scotland and have led to the deforested landscape seen today.