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We report eight new accelerator-mass spectrometer (AMS) radiocarbon ( 14 C) dates performed directly on individual bones of extirpated species from Crooked Island, The Bahamas. Three dates from the hutia (Geocapromys ingrahami), recovered from a culturally derived bone assemblage in , all broadly overlap from AD 1450 to 1620, which encompasses the time of first European contact with the Lucayan on Crooked Island (AD 1492). Marine fish and hutia dominate the bone assemblage at McKay's Bluff Cave, shedding light on vertebrate consumption by the Lucayans just before their demise. A fourth AMS 14 C date on a hutia bone, from a non-cultural surface context in Crossbed Cave (site CR-25), is similar (AD 1465 to 1645) to those from McKay's Bluff Cave. From Pittstown Landing (site CR-14), an open coastal archaeological site, a femur of the Cuban crocodile (Crocodylus rhombifer) yielded an AMS 14 C date of AD ∼1050-1250, which is early in the Lucayan cultural sequence. From a humerus in a non-cultural surface context in 1702 Cave (site

Some of the earliest studies of phylogenetic concordance involve native plants from the Pacific Northwest where many taxa showed clear genetic breaks between southern and northern populations. To test whether similar breaks also occur in invertebrate species with low dispersal capacities, genetic data from two mitochondrial genes are assembled for individuals of the arionid slug Prophysaon coeruleum throughout the species' range. Bayesian inference revealed three major clades and a total of eight subclades. It is argued that the demographic and genealogical past of P. coeruleum has resulted in a deep and shallow phylogeographical structure. The deep structure is at least 2.6-5.9 million years old and therefore clearly predates the Pleistocene period. Superimposed on this structure is a shallow structure that is most likely less than 2 million years old and probably the result of Pleistocene perturbations. Molecular analyses revealed that the three known colour traits in P. coeruleum do not represent monophyletic groups and that they do not match the patterns of genetic structure found. It is argued that the colour traits are perhaps a response to different levels of UV-radiation. The study adds to the increasing evidence that the phylogeographical structure of some taxa is more complex than previously thought. Moreover, it shows that genealogical concordance should not be deduced from phylogeographical patterns alone but should be based on an understanding of timing and causes of historical processes that lead to those patterns.