Vegetation composition and structure are important predictors of oviposition site selection in an alpine butterfly, the Mountain Ringlet Erebia epiphron

Knowledge of species’ ecological requirements is key for designing effective conservation management. In butterflies, the needs of larval stages are often the most specialised part of the life-cycle, but for many species information on this is lacking. The Mountain Ringlet Erebia epiphron is a cold-adapted butterfly found in alpine grasslands in mountainous regions of Europe. Efforts to devise conservation strategies for this climate change-threatened species are hampered due to its basic ecology being poorly understood. Here, we describe a study on the autecology of Mountain Ringlets at sites across its British distribution, focusing on the habitat preferences of egg-laying females as a proxy for larval preferences. Female Mountain Ringlets placed their eggs predominantly on Nardus stricta and Festuca ovina, but also on several other host plant species, suggesting larvae may be more broadly polyphagous than previously realised. Sites chosen for eggs had higher abundance of larval host plants, intermediate leaf litter cover, and lower cover of grass tussocks than random locations, as well as a shorter and sparser grass sward. Although the main host plant is ubiquitous in upland areas of Britain, our findings suggest that this butterfly’s egg and larval stages have specialised ecological requirements, requiring specific microhabitat features characterised by a narrow range of vegetation composition and structural characteristics. Many habitat associations are liable to be explicable as adaptations to ensure placement of eggs and larvae in sites within optimal (warm or buffered) microclimates. We tentatively suggest that the distribution of Mountain Ringlets in the landscape is thermally-constrained

Development of clinically relevant in vivo metastasis models using human bone discs and breast cancer patient-derived xenografts

Background Late-stage breast cancer preferentially metastasises to bone; despite advances in targeted therapies, this condition remains incurable. The lack of clinically relevant models for studying breast cancer metastasis to a human bone microenvironment has stunted the development of effective treatments for this condition. To address this problem, we have developed humanised mouse models in which breast cancer patient-derived xenografts (PDXs) metastasise to human bone implants with low variability and high frequency. Methods To model the human bone environment, bone discs from femoral heads of patients undergoing hip replacement surgery were implanted subcutaneously into NOD/SCID mice. For metastasis studies, 7 patient-derived xenograft tumours (PDX: BB3RC32, ER+ PR+ HER2−; BB2RC08, ER+ PR+ ER2−; BB6RC37, ER− PR− HER2− and BB6RC39, ER+ PR+ HER2+), MDA-MB-231-luc2, T47D-luc2 or MCF7-Luc2 cells were injected into the 4th mammary ducts and metastases monitored by luciferase imaging and confirmed on histological sections. Bone integrity, viability and vascularisation were assessed by uCT, calcein uptake and histomorphometry. Expression profiling of genes/proteins during different stages of metastasis were assessed by whole genome Affymetrix array, real-time PCR and immunohistochemistry. Importance of IL-1 was confirmed following anakinra treatment. Results Implantation of femoral bone provided a metabolically active, human-specific site for tumour cells to metastasise to. After 4 weeks, bone implants were re-vascularised and demonstrated active bone remodelling (as evidenced by the presence of osteoclasts, osteoblasts and calcein uptake). Restricting bone implants to the use of subchondral bone and introduction of cancer cells via intraductal injection maximised metastasis to human bone implants. MDA-MB-231 cells specifically metastasised to human bone (70% metastases) whereas T47D, MCF7, BB3RC32, BB2RC08, and BB6RC37 cells metastasised to both human bone and mouse bones. Importantly, human bone was the preferred metastatic site especially from ER+ PDX (100% metastasis human bone compared with 20–75% to mouse bone), whereas ER-ve PDX developed metastases in 20% of human and 20% of mouse bone. Breast cancer cells underwent a series of molecular changes as they progressed from primary tumours to bone metastasis including altered expression of IL-1B, IL-1R1, S100A4, CTSK, SPP1 and RANK. Inhibiting IL-1B signalling significantly reduced bone metastasis. Conclusions Our reliable and clinically relevant humanised mouse models provide significant advancements in modelling of breast cancer bone metastasis

Mouse Chromosome 3

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46995/1/335_2004_Article_BF00648421.pd

Winter availability of cereal stubbles attracts declining farmland birds and positively influences breeding population trends

Many studies have demonstrated the selection of stubble fields by farmland birds in winter, but none have shown whether provisioning of this key habitat positively influences national population trends for widespread farmland birds. We use two complementary extensive bird surveys undertaken at the same localities in summer and winter and show that the area of stubble in winter attracts increased numbers of several bird species of conservation concern. Moreover, for several farmland specialists, the availability of stubble fields in winter positively influenced the 10 year breeding population trend (1994–2003) whereas hedgerow bird species were less affected. For skylarks and yellowhammers, initially negative trends showed recovery with 10–20 ha of stubble per 1 km square. Thus, agri-environment schemes that promote retention of over-winter stubbles will attract birds locally and are capable of reversing current population declines if stubbles are available in sufficient quantity

Molecular determination of sex-ratio in Yellowhammer Emberiza citrinella offspring

Theory predicts skewed offspring sex-ratios in a range of situations in which the economics of producing the two sexes differ. Offspring sex-ratio skews in birds are relatively scarcely observed compared to other taxa. This could be because avian molecular sexing techniques, which allow young birds to be sexed, have only recently become available. Alternatively, birds may be largely constrained from adaptively manipulating the sex-ratio of their offspring. We used a recently-developed molecular sexing technique for birds to sex 420 Yellowhammer Emberiza citrinella offspring from 168 clutches found in Oxfordshire. Clutch sex-ratio of the population did not depart from the expected binomial distribution, and there was no variation in clutch sex-ratio with laying date, breeding attempt, or a variety of habitat variables which were predicted to differentially affect the survival and future reproductive success of offspring of the two sexes. There was no difference in size or growth rate of the sexes and nestling mortality was not sex-biased. Hence, although we can identify possible advantages of manipulating the sex-ratio in this species, it seems not to be used as a breeding strategy. Given the lack of consistent evidence for skewed avian offspring sex-ratios, more experimental work is required to determine whether, and how, birds may adaptively manipulate their offspring sex-ratio

Segregation in the African wintering ranges of English and Swiss Swallow Hirundo rustica populations: a stable isotope study

Capsule Stable isotope analysis of Swallow feathers, grown in Africa, revealed significant differences between populations breeding in Switzerland and England. Aims To investigate the extent to which Swallow populations breeding in Switzerland and England are separated on their African wintering grounds. Methods Swallows were caught at breeding colonies, biometric measurements were taken and feathers, grown in Africa, were collected. Feathers were combusted in a Carlo Erba C/N/S analyser and the delta(13)C and delta(15)N signatures were measured using a mass spectrometer. Results The delta(13)C signatures of Swiss birds were significantly more depleted than those of birds from England. The delta(15)N signatures did not differ between the two populations. Conclusion Birds from Switzerland and England probably winter in geographically distinct parts of Africa. The Swiss birds probably feed on prey that are more reliant on C-3 vegetation, from woodlands, than the prey of English birds, which are more reliant on C-4 vegetation, from grasslands