Taxonomic status of the extinct Canary Islands Oystercatcher Haematopus meadewaldoi

Mitochondrial genes were sequenced from four specimens of the extinct Canary Islands Oystercatcher Haematopus meadewaldoi and compared with African Oystercatcher Haematopus moquini, Eurasian Oystercatcher Haematopus ostralegus and an old unidentified extralimital ‘black’ oystercatcher specimen from The Gambia. At these loci, H. meadewaldoi was approximately 99.65% identical to multiple Eurasian Oystercatcher samples and in phylogenetic trees fell within the range of genetic variation observed in that species. The mystery Gambian bird was resolved as an extralimital H. moquini. We conclude that H. meadewaldoi was most likely a recently diverged melanistic morph or subspecies of H.ostralegus, although further genomic studies will be required to determine whether there has been a period of isolation followed by introgression

Inferring Deleterious-Mutation Parameters in Natural Daphnia Populations

Deng and Lynch (1, 2) proposed to characterize deleterious genomic mutations from changes in the mean and genetic variance of fitness traits upon selfing in outcrossing populations. Such observations can be readily acquired in cyclical parthenogens. Selfing and life-table experiments were performed for two such Daphnia populations. A significant inbreeding depression and an increase of genetic variance for all traits analyzed were observed. Deng and Lynch's (2) procedures were employed to estimate the genomic mutation rate (U), mean dominance coefficient ( [Image: see text] ), mean selection coefficient ( [Image: see text] ), and scaled genomic mutational variance ( [Image: see text] ). On average, [Image: see text] , [Image: see text] , [Image: see text] and [Image: see text] (^ indicates an estimate) are 0.84, 0.30, 0.14 and 4.6E-4 respectively. For the true values, the [Image: see text] and [Image: see text] are lower bounds, and [Image: see text] and [Image: see text] upper bounds

Community and the creation of provincial identities: a re-interpretation of the aisled building at North Warnborough

The aisled hall at North Warnborough has attracted attention as one of a handful of examples frequently included in surveys and analyses of this common architectural type as well as for arguments related to the gendered use of space. This article presents a new architectural analysis of this building and attempts to set it within its immediate and wider archaeological and geological landscape context. A theoretically informed interpretation of the social significance of this site is offered, which has broader implications for the studies of Romano-British architecture, rural settlement, and landscape

IODP Expeditions 309 and 312 drill an intact section of upper oceanic basement into gabbros

The Integrated Ocean Drilling Program's (IODP) Expeditions 309 and 312 successfully completed the first sampling of an intact section of upper oceanic crust, through lavas and the sheeted dikes into the uppermost gabbros. Hole 1256D, which was initiated on the Ocean Drilling Program's (ODP) Leg 206, now penetrates to >1500 mbsf and >1250 m sub-basement. The first gabbroic rocks were encountered at 1407 mbsf. Below this, the hole penetrates 3c100 m into a complex zone of fractionated gabbros intruded into contact metamorphosed dikes