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The mating system of sciomyzoid flies is typified by vigorous premating struggles and a large male mating advantage. Females commonly exhibit three behaviours (shaking, kicking and curling) during struggles. We tested the predictions of three hypotheses proposed to explain the evolution of female resistance in Coelopa frigida. Both shaking and curling were associated with reduced female mating rate and thus appear to be resistance traits. Mounts that ended while the female was curling appeared to be terminated by the male dismounting from the female rather than as a result of resistance. The communication hypothesis proposes that female resistance functions by signalling to the male that the female is unwilling to mate to encourage males to dismount them. Curling therefore seems to fit the predictions of the communication hypothesis. Shaking was associated with sexual selection for large male size and also males that could withstand resistance the longest. These observations fit with the predictions of both the female reluctance and screening hypotheses. Furthermore, shaking was associated with a pattern of mating that increased offspring fitness. This did not occur in females that did not shake. This corresponds with the predictions of the screening hypothesis that resistance generates indirect sexual selection. However, our results are also largely consistent with the female reluctance hypothesis. It appears that different resistance behaviours may have different functions, and furthermore that individual resistance behaviours might generate different mating rates and patterns of sexual selection between female karyotypes.

The courtship song of Drosophila is useful for species recognition and sexual selection. A new species of the melanogaster group of Drosophila, D. santomea, has recently been described from the island of Sao Tomein the Gulf of Guinea. We describe the courtship song of D. santomea and compare it with that of its sibling species D. yakuba. Both species have a relatively unusual song pattern for melanogaster-group species, in that they have two types of pulse song but no sine song. There are large dif- ferences in the inter-pulse interval of both types of song, but no major differences in pulse shape or intrapulse frequency between the species. The song of D. yakuba is similar in lines from the African mainland (allo- patric to D. santomea) and from Sao Tome´ (sympatric). We test if song pattern might influence sexual isolation by examining the mating suc- cess of wingless males with homo- and hetero-specific females. We show that song pattern contributes to sexual stimulation, but the differences in song patterns alone are unlikely to explain patterns of sexual isola- tion such as the asymmetrical isolation seen between species.

1. Coastal organisms are predicted to be particularly susceptible to the impact of global warming. In this study the distribution and relative abundance of two coastal invertebrates, Coelopa frigida (Fabricius) and C. pilipes are investigated. 2. Coelopa pilipes has a more southerly distribution than C. frigida, and prefers a warmer climate. Coelopa pilipes is less resistant to sub-zero temperatures than C. frigida and its northerly distribution is probably limited by cold winter days. 3. The most recent distribution map of C. frigida and C. pilipes in northern Europe was published a decade ago and showed the northerly extent of the distribution of C. pilipes reaching the north coast of mainland Scotland but its complete absence from the Western and Northern Isles. 4. C. pilipes has now spread throughout the Western Isles and the Orkney Islands but is still absent from Shetland. There has also been an increase in the relative frequency of C. pilipes at sites harbouring coelopids on the British mainland. A similar pattern of distribution change along the west coast of Sweden is reported. 5. It is proposed that these changes have occurred primarily as a result of global warming and in particular due to the recent increase in winter temperatures. A number of other indirect effects may have also contributed to these changes, including a probable change in macroalgae distribution. The implications of these changes for the wrack bed ecosystem and at higher trophic levels are considered.

Marine protected areas are advocated as an essential management tool to ensure the sustainable use of ma- rine resources by providing insurance against over-exploitation and through the provision of refuge for a large biomass of sexually mature adults. Using a unique fishing gear-restriction, voluntary management system as a large-scale exper- iment, we found that adult scallops (Pecten maximus) within areas protected from towed bottom-fishing gear had heavier adductor muscle tissue and gonads that were 19%-24% heavier than those of scallops in fished areas, while other body and age characteristics were similar in both areas. The scallops within the protected area also occurred at a much higher abundance than adjacent, chronically fished (× 12.83) and wider commercially exploited (× 2.18) areas. These results provide evidence that the use of towed bottom-fishing gear can further exacerbate the effects of overfish- ing through the suppression of the reproductive potential of individuals of similar body size. These findings underline the utility of using closed areas as tools for fisheries conservation of sedentary species of commercial importance. Resume : On recommande les zones de protection marine comme outils essentiels de gestion afin d'assurer l'utilisation durable des ressources marines, car elles procurent une assurance contre la surpeche et des refuges pour une importante biomasse d'adultes arrives a la maturite sexuelle. En utilisant un systeme de gestion inedit de restriction volontaire des engins de peche comme experience a grande echelle, nous observons que, dans les zones protegees ou les engins de peche tires sur le fond ne sont pas utilises, les petoncles adultes (Pecten maximus) ont le tissu du muscle adducteur et les gonades de 1 9%a2 4 %plus lourds que les petoncles des zones exploitees; les autres caracteristiques du corps et de l'âge sont, par ailleurs, semblables dans les deux zones. Les petoncles de la zone protegee ont aussi une densite beaucoup plus grande que celles de la zone adjacente soumise chroniquement a la peche (× 12,83) et des zones plus eloignees exploitees commercialement (× 2,18). Ces resultats montrent que l'utilisation d'engins de peche traines sur le fond peut amplifier les effets de la surpeche en reduisant le potentiel reproductif des individus de taille correspondante. Ces observations soulignent l'interet d'utiliser les zones fermees comme outils de conservation halieutique chez les especes sedentaires d'importance commerciale. (Traduit par la Redaction) Kaiser et al. 1289

Coelopids live in wrack beds consisting of seaweed washed up on beaches. Their mating system is characterized by sexual conflict and convenience polyandry, with females resisting male mating attempts. We estimated the level of harassment by males and the success rate of rejection by females collected from a high density wild population. Males mounted a female every 8.41 min. Of these mounts 35% resulted in copulation. This suggests that females could be mated up to 5 times every 2 h. Females typically live for 3 weeks, and thus, could mate with hundreds of males during their lifetime. We found a 50:50 sex ratio throughout the wrack bed revealing that females do not avoid male harassment by leaving the wrack bed when not ovipositing.

The seaweed fly, Coelopa frigida, exhibits LMSP. A large chromosomal inversion system affects many traits including egg-to-adult viability via heterosis. Consequently, there is also considerable potential for cryptic female mate choice to operate on the basis of sperm karyotype. Here, we investigated the effect of time interval and chromosomal inversion karyotype on postcopulatory sexual selection. Homokaryotypic females were mated with a male of the same and a male of the opposite homokaryotype. The order of the matings was varied so cryptic female mate choice could operate either in concert or antagonistically with LMSP. LMSP was found when there was a 24 h time interval between matings, irrespective of the order in which the males were mated. However, when the males were mated in quick succession the order of mating was important. When LMSP and cryptic female mate choice work in concert a high level of LMSP was found. However, when the male of opposite homokaryotype mated first, then first male sperm precedence was observed. This suggests that polyandrous females might be able to bias paternity but only when matings occur in quick succession. Consequently, population density is likely to affect the operation of postcopulatory sexual selection.

Summary 1 The impacts of trawls and dredges on marine benthic habitats and communities have been studied extensively, but mostly at small scales and over short time periods. To investigate the large-scale chronic impacts of towed fishing gears, zoned commercial fishery management systems allow comparison of habitats and communities between areas of seabed subjected to varying levels of towed-gear use. 2 The Inshore Potting Agreement (IPA) was implemented in 1978 to restrict the use of towed gears in inshore areas that had traditionally been used by static-gear (pot and net) fishers. We used scallop dredges to sample benthic communities at sites within and adjacent to the IPA area that had been subjected to four different commercial fishing regimes since the inception of the system. These were: (i) towed gears only, (ii) annual, seasonal towed-gear use, (iii) temporary towed-gear use but reverting to static-gear use 18–24 months prior to sampling, and (iv) static gears only. 3 There were no significant differences in the total species richness or biomass of benthic communities between sites under regimes (i) and (ii). There was significantly greater total species richness and biomass of benthic communities at sites under regimes (iii) and (iv) than at sites under regimes (i) and (ii). The benthic community biomass under regime (iv) was significantly greater than under all other regimes. 4 The IPA has maintained benthic species that are important for the settlement and survival of others. The cessation of towed-gear fishing for a period of greater than 2 years would be necessary for benthic communities in areas adjacent to the IPA to recover such that they were indistinguishable from areas where towed gears had not been used. 5 Synthesis and applications. Members of the fishing industry may object to the creation of permanent closed areas because harvestable stocks can move in space and time. This study indicates that zoned fishery management can allow some sectors of the fishing industry to retain access to fishery resources while protecting benthic species and habitats.

The management of fisheries in European Union (EU) waters has generally been regulated through government institutions and agreed quota allocations. This top-down management approach may have contributed to the continued decline of targeted fish stocks by forcing fishers to compete for limited resources without engendering a sense of resource stewardship. In attempting to reverse this decline, scientists and managers should examine management systems that do not solely depend on top-down approaches, and the Inshore Potting Agreement (IPA) is an example. The IPA is a voluntary fishery management system designed and operated by inshore fishers of south Devon, England. The IPA was conceived to reduce conflict between static-gear (pot and net) and towed-gear (trawl and dredge) fishers, and is regarded as a successful fisheries management regime by fishers and managers because it has effectively allowed fishers from both sectors to operate profitably on traditional fishing grounds. Another study determined that the IPA has incidentally protected benthic habitat complexity. Fishers from the static-gear and towed-gear sectors were interviewed to determine the evolution and function of the IPA, and to establish the factors that ensure the high level of regulatory compliance amongst fishers from both sectors. Towed-gear fishers gave significantly different responses to the same questions asked of static-gear fishers, and were generally less satisfied with the existence of the IPA. Multivariate analyses of the interview data suggested that fishers who thought the IPA was a good system also thought the system provided pot protection, but had experienced inter-sector conflict. Fishers who thought the IPA provided no personal benefit also thought that static-gear fishers should be more restricted, and that towed-gear corridors or more seasonal-use areas should be established within the existing IPA area. However, fishers from both sectors agreed that the IPA has maintained traditional practices of the local fishing industry, and that the system has conserved target finfish and scallop species. A number of factors were identified as critical to the success of the IPA. These included the voluntary nature of the agreement, the limited number of organizations representing fishers and very high level of membership of those organizations, and the simplicity of the system. Regulatory compliance is enhanced through the ability of fishers' organizations to respond rapidly to inter-sector conflict issues.

Cross border reproductive treatment has provoked extensive commentary, ethical debate and media speculation. There is however, little published empirical data on the extent of this phenomenon, the reasons why people undertake cross border treatment and their experience of it. A survey of clinics in Belgium reported that the desire to evade legal restrictions in their home country was the main motivation for patients accessing treatment in Belgium. However, few UK patients were included in this sample. An unpublished study of 6 European countries by an ESHRE taskforce also suggested that most patients cross borders because of ‘legal’ restrictions in their home countries. However, given the differing legal and regulatory contexts and availability of publically funded IVF, the driving forces for cross-border care will vary from country to country. This paper reports preliminary data from an ESRC funded qualitative study (http://www.transrep.co.uk/), which aimed to explore the motivations, understandings and experiences of UK based individuals who travel abroad for assisted reproductive treatment (RES-000-22-3390).

Land models, which have been developed by the modeling community in the past two decades to predict future states of ecosystems and climate, have to be critically evaluated for their performance skills of simulating ecosystem responses and feedback to climate change. Benchmarking is an emerging procedure to measure and evaluate performance of models against a set of defined standards. This paper proposes a benchmarking framework for evaluation of land models. The framework includes (1) targeted aspects of model performance to be evaluated; (2) a set of benchmarks as defined references to test model performance; (3) metrics to measure and compare performance skills among models so as to identify model strengths and deficiencies; and (4) model improvement. Component 4 may or may not be involved in a benchmark analysis but is an ultimate goal of general modeling research. Land models are required to simulate exchange of water, energy, carbon and sometimes other trace gases between the atmosphere and the land-surface, and should be evaluated for their simulations of biophysical processes, biogeochemical cycles, and vegetation dynamics across timescales in response to both weather and climate change. Benchmarks that are used to evaluate models generally consist of direct observations, data-model products, and data-derived patterns and relationships. Metrics of measuring mismatches between models and benchmarks may include (1) a priori thresholds of acceptable model performance and (2) a scoring system to combine data-model mismatches for various processes at different temporal and spatial scales. The benchmark analyses should identify clues of weak model performance for future improvement. Iterations between model evaluation and improvement via benchmarking shall demonstrate progress of land modeling and help establish confidence in land models for their predictions of future states of ecosystems and climate.

The Joint UK Land Environment Simulator (JULES) is a process-based model that simulates the fluxes of carbon, water, energy and momentum between the land surface and the atmosphere. Past studies with JULES have demonstrated the important role of the land surface in the Earth System. Different versions of JULES have been employed to quantify the effects on the land carbon sink of separately changing atmospheric aerosols and tropospheric ozone, and the response of methane emissions from wetlands to climate change. There was a need to consolidate these and other advances into a single model code so as to be able to study interactions in a consistent manner. This paper describes the consolidation of these advances into the modelling of carbon fluxes and stores, in the vegetation and soil, in version 2.2 of JULES. Features include a multi-layer canopy scheme for light interception, including a sunfleck penetration scheme, a coupled scheme of leaf photosynthesis and stomatal conductance, representation of the effects of ozone on leaf physiology, and a description of methane emissions from wetlands. JULES represents the carbon allocation, growth and population dynamics of five plant functional types. The turnover of carbon from living plant tissues is fed into a 4-pool soil carbon model. The process-based descriptions of key ecological processes and trace gas fluxes in JULES mean that this community model is well-suited for use in carbon cycle, climate change and impacts studies, either in standalone mode or as the land component of a coupled Earth system model.

Marine protected areas, and other fishery management systems that impart partial or total protection from fishing, are increasingly advocated as an essential management tool to ensure the sustainable use of marine resources. Beneficial effects for fish species are well documented for tropical and reef systems, but the effects of marine protected areas remain largely untested in temperate waters. We compared trends in sport-fishing catches of nine fish species in an area influenced by a large (500-km2) towed-fishing-gear restriction zone and in adjacent areas under conventional fishery management controls. Over the period 1973–2002 the mean reported weight of above-average-sized (trophy) fish of species with early age at maturity and limited home range was greatest within the area influenced by the fishing-gear restriction zone. The reported weight of trophy fish of species that mature early also declined less and more slowly over time within the area influenced by the fishing-gear restriction zone. Importantly, the mean reported weight of trophy fish of species that mature late and those that undertake extensive spatial movements declined at the same rate in all areas. Hence these species are likely to require protected areas >500 km2 for effective protection. Our results also indicated that fish species with a localized distribution or high site fidelity may require additional protection from sport fishing to prevent declines in the number or size of fish within the local population.

Egg sharing is an arrangement in which a woman is offered free or reduced-cost assisted conception treatment in return for 'donating' oocytes for the treatment of another woman, the cost of her treatment being subsidized by the recipient of her oocytes. Egg sharing has been developed for a variety of reasons: to ameliorate donor oocyte shortages, to avoid potential health risks to non-patient donors and, given the limited availability of publicly funded assisted conception treatment in the UK, to make treatment more readily available to individuals on lower incomes, thus expediting treatment by reducing waiting lists. This paper outlines the development and current status of egg sharing in the UK through analysis of responses to a consultation on payment to gamete donors initiated by the Human Fertilisation and Embryology Authority (HFEA) and the HFEA's Guidance for Egg Sharing Arrangements.

Cloned plants were grown in growth-chambers for 82 days under day/night temperatures of 15° 10°, 20°/10°, 20°/1 So, 2So/1So, and 2So/20°C. Dry matter yields were greatest at 25°C daytime temperatures. Solanum laciniatum also grew well in the coldest conditions, whereas growth of S. aviculare was depressed at the two lowest temperatures. Solasodine concentrations in leaves and particularly in sterns were lower at the warrnest temperatures. Total solasodine yield per plant remained approximately constant because of compensatory vegetative growth, except at the two temperature extremes. Fruiting was greatly enhanced by 20°/10°C treatment of S. laciniatum but S. aviculare did not respond. Severe moisture stress limited growth but increased solasodine concentrations in sterns and leaves; total solasodine production was reduced. A field trial showed that mild moisture stress, from withholding irrigation, lowered dry matter yields but had no effect on solasodine concentration, i.e., solasodine productio...

(1848). XLVIII.—Corrections of “Critical remarks on Mr. Gray's Catalogue of Mammalia and birds presented by B. H. Hodgson, Esq., to the British Museum,” Ann. and Mag. N. H. vol. xx. p. 313. Annals and Magazine of Natural History: Vol. 1, No. 6, pp. 454-457.

Growing-stock removals for products have increased by 12% in the Lake States since 1983. Regional gains are led by red pine, aspen, and other hardwoods. New mills and technology promise to further improve markets for underutilized species throughout the region.

Discusses and analyzes fuelwood production in rural Minnesota from roundwood and primary wood-using mill residue. Compares production in 1975 with production in 1960 and 1970. Assesses outlook for future fuelwood production and potential impact on Minnesota's forest industry.

Discusses 1979 production and receipts and recent production for other years in the Lake and Central States. Shows Michigan, Minnesota, and Wisconsin production by species for each county and compares production by Forest Inventory Unit with that of previous years. Presents 1979 production and receipts data for Illinois, Indiana, Iowa, and Missouri, and shows four production classes by county.