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In contrast to the rich collections of articulated spiny-rayed fishes from early Late Cretaceous and Eocene Lagerstätten, similar skeletal remains are sparse in Maastrichtian-Paleocene strata. Here we coin this poorly understood span "Patterson's Gap" and review known articulated skeletons from it, summarizing available information on their phylogenetic affinities, age, and environmental context. Roughly fifty percent of taxa in both the Maastrichtian and Paleocene come from Europe and North America, with percomorphs representing around 60% of the skeletal acanthomorph taxa in each interval. This is higher than the only pre-Maastrichtian assemblage with a reasonable sample of percomorphs, but lower than most Eocene and younger sites. Fossils from Patterson's Gap show a steady accumulation of the principal lineages of spiny-rayed fishes. Material from Paleocene or older strata provides evidence for most of the roughly 20 major acanthomorph divisions recovered by molecular studies. Many fossils from Patterson's Gap remain undescribed and unnamed, and almost none have been included within formal phylogenetic analyses. Revision of existing material, combined with additional fieldwork, should be a priority for future efforts seeking to clarify this murky but significant interval in the evolutionary history of a major vertebrate radiation. [ABSTRACT FROM AUTHOR]

The history of the infilling of the North Sea is outlined, with particular focus on sediment sources and river inputs. In simple terms (for the detail is complex), these sources changed from domination by northwesterly sources from the Shetland area (Paleocene to Eocene), to a geographically more uniform basin-centred pattern, and then northerly input following Fennoscandian uplift (Oligocene and Neogene). Baltic inputs followed via an 'Eridanos (Baltic) River' (Miocene), with cold-climate coarser sediment inputs, and lacustrine episodes resulting from ice damming (Pleistocene). River styles in each of these phases are discussed, with the Cenozoic at first being dominated by low energy fluvial deposition (channel sands, chemically weathered clays, and organic sedimentation) in fluctuating climates. Cold climates in the latest Neogene and Quaternary are seen as major determinant of a change in fluvial style, though these are also associated with tectonic effects, as in Scandinavia. The mediating role of vegetation, relating also to temperature and precipitation, is also likely to have been significant. Narrow valley incision followed the Middle Pleistocene Transition, as well as an increasing importance of Rhine-Meuse sources that had begun earlier. [ABSTRACT FROM AUTHOR]