Parasitoid sex ratios can be greatly influenced by mating and dispersal behaviour. Many sex ratio models assume that mating is strictly local (only mated females disperse from the natal patch) and that a single male is sufficient to inseminate all females in a brood. Bethylids (acukdte parasitoids) have been used to test predictions of these models, but less attention has been paid to testing their underlying assumptions. We investigated the timing of eclosion, mating and dispersal in mixed-sex and single-sex broods of the bethylid wasp Goniozus nephanridis. In mixed-sex broods, almost all females mate before dispersal and a single male is sufficient to inseminate virtually all females, even when brood sizes are large. Males disperse from both mixed-sex and all-male broods, but males in all-male broods disperse more slowly. Virgin females disperse from all-female broods, which are common. Virgin females can produce a brood, mate with their own sons and subsequently produce mixed-sex broods, but their Success rate is very low. Virgin females could potentially circumvent sex allocation constraints by superparasitizing mixed-sex broods, but when presented with hosts bearing mixed-sex broods they destroy all members of the initial brood before ovipositing. Because of the high prevalence of singlesex broods and dispersal of both sexes, the mating structure of C. nephantidk is unlikely to conform to the assumption of strict local mating.

Compared to using constant RBE, the variable RBE models predicted increased biological doses to the rectum, bladder and prostate, which in turn lead to substantially higher estimated rectum and bladder NTCPs.

There is mounting evidence for the non-analogue nature of Late Glacial ecosystems. This period also witnessed several dispersal episodes of human forager groups moving, for the first time, into previously uninhabitable glacial or periglacial landscapes. In palaearctic northern Europe, these dispersals are associated with a succession of archaeological technocomplexes that are traditionally thought to reflect changing adaptation strategies synchronised with contemporaneous environmental changes. Recent investigations into ecological disequilibrium dynamics suggest, however, that there may be a greater degree of mismatch between organisms and their environments, especially in arctic-type environments and during times of rapidly changing climate. We link these climatic changes to cultural changes via demographic inference. Based on recent dating evidence, environmental analyses and preliminary 2 morphometric and technological analyses of lithic material, we here develop the argument that these Late Glacial Palearctic foragers were similarly at disequilibrium and that coupled with their very low population densities were prone to regional extinction episodes. We focus in particular on the so-called 'Hamburgian culture' and its potentially failed dispersal into southern Scandinavia.

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