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Farm Business Survey, 1984-1985: Special Licence Access;;Farm Business Survey, 1982- : Special Licence Access
- 负责人：
- 关键词：
- DOI：
- doi:10.5255/ukda-sn-2384-1
- 摘要：
- For the second edition (February 2010), the data and documentation have been updated. This study was previously held in the form of SPSS files
GBIF Occurrence Download
- 负责人：
- DOI：
- doi:10.15468/dl.usnjuk
- 摘要：
- présence occasionnelle communale (réseau Loup-Lynx ONCFS). 157 records from Loup 2009 présence régulière communale (réseau Loup-Lynx ONCFS). 221
Farm Business Survey, 1990-1991: Special Licence Access;;Farm Business Survey, 1982- : Special Licence Access
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- 关键词：
- DOI：
- doi:10.5255/ukda-sn-2945-1
- 摘要：
- For the third edition (February 2010), the data format and documentation have been updated. This study was previously held in the form of SPSS files
GBIF Occurrence Download
- 负责人：
- DOI：
- doi:10.15468/dl.bmiamp
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- Muir Trust - Species Records for John Muir Trust Properties 2007-2009. 16 records from iNaturalist research-grade observations. 4 records from North
GBIF Occurrence Download
- 负责人：
- DOI：
- doi:10.15468/dl.h5llfs
- 摘要：
- Visual Census 1998. 528 records from Florida Keys Reef Visual Census 2000. 741 records from Florida Keys Reef Visual Census 2010. 1006 records from
GBIF Occurrence Download
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- DOI：
- doi:10.15468/dl.wrbnbu
- 摘要：
- records from RSPB - Bird survey records from RSPB's London House Sparrow Parks Project 2009-2010, covering 19 London parks and surrounding streets (Funded
Data from: Diverse reproductive barriers in hybridising crickets suggests extensive variation in the evolution and maintenance of isolation
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- DOI：
- doi:10.5061/dryad.sh53j
- 摘要：
- Reproductive barriers reduce gene flow between populations and maintain species identities. A diversity of barriers exist, acting before, during and after mating. To understand speciation and coexistence, these barriers need to be quantified and their potential interactions revealed. We use the hybridising field crickets Gryllus bimaculatus and G. campestris as a model to understand the full compliment and relative strength of reproductive barriers. We find that males of both species prefer conspecific females, but the effect is probably too weak to represent a barrier. In contrast, prezygotic barriers caused by females being more attracted to conspecific male song and preferentially mounting and mating with conspecifics are strong and asymmetric. Postzygotic barriers vary in direction; reductions in fecundity and egg viability create selection against hybridisation, but hybrids live longer than pure-bred individuals. Hybrid females show a strong preference for G. bimaculatus songs, which together with a complete lack of hybridisation by G. campestris females, suggests that asymmetric gene flow is likely. For comparison, we review reproductive barriers that have been identified between other Gryllids and conclude that multiple barriers are common. Different species pairs are separated by qualitatively different combinations of barriers, suggesting that reproductive isolation and even the process of speciation itself may vary widely even within closely related groups.
Data from: Spread of amphibian chytrid fungus across lowland populations of Túngara frogs in Panamá
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- DOI：
- doi:10.5061/dryad.6bp92
- 摘要：
- y be infected but asymptomatic. Here we describe the spread (2009 to 2014) of Bd across lowland habitats east of the Panamá Canal (< 500 m a.s.l.) with a focus
Data from: The foraging ecology of the Mountain long-eared bat Plecotus macrobullaris revealed with DNA mini-barcodes
- 负责人：
- DOI：
- doi:10.5061/dryad.611310kt
- 摘要：
- faeces from individual Mountain long-eared bats Plecotus macrobullaris trapped using mist nets during the summers of 2009 and 2010 in the Pyrenees
Data from: Do deposit-feeders compete? Isotopic niche analysis of an invasion in a species-poor system
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- DOI：
- doi:10.5061/dryad.72j0n
- 摘要：
- Successful establishment of invasive species is often related to the existence of vacant niches. Competition occurs when invaders use the same limiting resources as members of the recipient community, which will be reflected in some overlap of their trophic niches. The concept of isotopic niche has been used to study trophic niche partitioning among species. Here, we present a two-year field study comparing isotopic niches of the deposit-feeding community in a naturally species-poor system. The isotopic niche analyses showed no overlap between a recent polychaete invader and any of the native species suggesting that it has occupied a vacant niche. Its narrow isotopic niche suggests specialized feeding, however, the high d15N values compared to natives are most likely due to isotope fractionation effects related to nitrogen recycling and a mismatch between biological stoichiometry of the polychaete and the sediment nitrogen content. Notably, highly overlapping isotopic niches were inferred for the native species, which is surprising in a food-limited system. Therefore, our results demonstrate that invaders may broaden the community trophic diversity and enhance resource utilization, but also raise questions about the congruence between trophic and isotopic niche concepts and call for careful examination of assumptions underlying isotopic niche interpretation.
