Minerals and the Common Fund for Commodities

This paper reviews the role of minerals in the Integrated Programme for Commodities and the objectives and problems of the Second Account of the Common Fund for Commodities (CFC). It focuses on the least developed countries in Africa, providing specific suggestions for R&D to improve mineral exploration techniques in rain forest and savanna regions; to reduce mine exploration costs; to design equipment suitable for mining narrow veins; to improve concentrating methods for certain ores and to optimize byproduct recovery; to reduce environmental impacts; and to use the waste products of mining. It also discusses demand oriented CFC projects and their policy implications.     

Territory dynamics in a sage sparrow population: are shifts in site use adaptive?

Summary In 1981–1985, we studied territory dynamics in a southeastern Idaho sage sparrow population to evaluate the hypothesis that territory shifts represent adaptive adjustments in site use. We predicted that shifts should (1) result in changes in territory characteristics, (2) be influenced by previous reproductive success and result in greater success, and (3) decline in magnitude for individual males over time. Habitat features of territories changed little as a result of shifts, but territory size increased. Correspondingly, habitat features of territories were unrelated to reproductive success, whereas territory size was positively related. The magnitude of territory shifts was negatively correlated with preshift fledging success, and after shifts, males experienced greater average reproductive success than before. Successive territory shifts by individual males became progressively smaller. Thus, territory shifting by sage sparrows seems to be adaptive behavior aimed primarily at increasing territory size.     

Mating system of the hermaphroditic coral-reef fish,Serranus baldwini

Summary The lantern bass, Serranus baldwini, is a small hermaphroditic serranid found adjacent to coral reefs throughout the Caribbean. Data from gonad inspection, spawning behavior, and gamete release from individuals all confirm that populations consist of simultaneous hermaphrodites and males. This gender pattern appears to be sequential, with larger males derived from smaller hermaphrodites. The social system is haremic, with the male defending an area containing 1–7 hermaphrodites. The social system and gender pattern are similar to those of the eastern Pacific serranid, Serranus fasciatus. Males obtain disproportionately high mating success by being nearly the sole mates of hermaphrodites within their harems. Hermaphrodites obtain very low levels of mating success through male function. This pattern may result from female choice by hermaphrodites, mate sequestering tactics by males, or both. The serranids that change gender from hermaphrodite to male appear to have a higher environmental potential for polygyny than other simultaneous hermaphrodites in this family. Factors that may maintain male function in hermaphroditic S. baldwini are outlined, but none currently provides clear evidence for why this species has not evolved to protogyny.     

Temporal trends of organochlorine contamination in Black Guillemots in Iceland from 1976 to 1996

The levels of several different persistent organochlorines (OCs) in Black Guillemots Cepphus grylle, collected during the summers of 1976-1996 at Breioafj?rour in W-Iceland, were investigated. The levels of about 40 different organochlorines (PCBs, DDTs, chlordanes, toxaphenes, HCH, HCB) were compared with respect to age, sex, fat content, and year of collection. The levels of PCBs correlated very closely with those of DDE, indicating long-range transport as the major source of these contaminants in Iceland, with the ratio PCBs/DDE mostly in the range of 2-5. Unlike the Gyrfalcon Falco rusticolus, the organochlorine levels did not seem to accumulate substantially with age, neither in males nor females. The variation in the levels of OCs at the age of 2 years was even greater than the variation in OC levels over an age range of 12 years. In immature birds the levels of PCBs, DDE, HCB and beta-HCH declined very slowly (T(1/2) from 12 to 20 years) over the years 1976-1996, whereas the levels of alpha-HCH and p,p'-DDT declined much faster. The levels of trans-nonachlor, alpha-chlordane, gamma-chlordane, oxychlordane, and toxaphene did not correlate with the year of collection. As the Black Guillemot is mostly a resident seabird, feeding mainly on small fish and invertebrates, this investigation should give a good indication of the temporal trends of organochlorine pollution at Breioafj?rour, Iceland, during this 20 year period and is likely to reflect baseline trends in the marine environment of the North-Atlantic Ocean.     

Conceiving a fetus for bone marrow donation: An ethical problem in prenatal diagnosis

We present a family who sought prenatal diagnosis in order to bear a healthy child to serve as an HLA–identical bone marrow donor for their son affected with Wiskott–Aldrich syndrome. They intended to abort HLA-incompatible fetuses who would have been unsuitable bone marrow donors. This case led us to conclude that prenatal diagnosis should not be used to benefit a third party or facilitate the conception or abortion of a fetus for the purpose of generating an organ for transplantation. The limits of parental autonomy and physician responsibility are discussed.     

Historical demography and contemporary spatial genetic structure of an estuarine crab in the northeast Pacific (<Emphasis Type="Italic">Hemigrapsus oregonensis</Emphasis>)

Discrete estuary subpopulations of the mud crab Hemigrapsus oregonensis (Dana, 1851) are connected via larval dispersal. Sequence variation at the mtDNA COI locus was examined in eight populations sampled in 2001–2002 from central California through northern Oregon in the northeast Pacific (36.6–45.8°N) to infer patterns of dispersal and historical connectivity in the region. Strong evidence for persistence since the mid-Pleistocene, with no range truncation resulting from southward shifting temperature isoclines, was provided by a phylogeographic pattern of haplotypes of an older clade distributed throughout the sampled range. A recently derived clade became widespread only north of Cape Blanco after the last glacial maximum. Its clear pattern of restriction to the northern area, in the absence of similarly restricted southern clades, suggests that contemporary dispersal around Cape Blanco is rare (population F _ST = 0.192). Low pairwise differentiation within Oregon and within central California, as well as contrasts between northern and southern groups in the shape of the pairwise mismatch distribution, nucleotide diversity, and Tajima’s D suggest that these regions reflect different demographic histories. Potential mechanisms explaining this latitudinal break include contemporary coastal circulation patterns, selection, and ancient patterns of larval dispersal in the California Current.