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ABSTRACT In this paper we document the pattern of geographic variation in song of the Corn Bunting in a marked population in Sussex. Song variation is best described as a system of local dialects with three song types in each dialect. We examine the inheritance of dialects from father to son; sons sing the same dialect as their nearest neighbour, rather than inheriting the dialect of the father. Therefore songs seem to be learned after dispersal. We also compare the dialects of mates and fathers of females: our results suggest that females do not rely on dialects when pairing. These results are discussed in the context of the current controversy surrounding other species with dialects and hypotheses relating dialects to the genetic structure of populations. 相似文献
104.
Yang SY Saxena RK Kulwal PL Ash GJ Dubey A Harper JD Upadhyaya HD Gothalwal R Kilian A Varshney RK 《Journal of genetics》2011,90(1):103-109
With an objective to develop a genetic map in pigeon pea (Cajanus spp.), a total of 554 diversity arrays technology (DArT) markers showed polymorphism in a pigeon pea F2 mapping population of 72 progenies derived from an interspecific cross of ICP 28 (Cajanus cajan) and ICPW 94 (Cajanus scarabaeoides). Approximately 13% of markers did not conform to expected segregation ratio. The total number of DArT marker loci segregating
in Mendelian manner was 405 with 73.1% (P > 0.001) of DArT markers having unique segregation patterns. Two groups of genetic maps were generated using DArT markers.
While the maternal genetic linkage map had 122 unique DArT maternal marker loci, the paternal genetic linkage map has a total
of 172 unique DArT paternal marker loci. The length of these two maps covered 270.0 cM and 451.6 cM, respectively. These are
the first genetic linkage maps developed for pigeon pea, and this is the first report of genetic mapping in any grain legume
using diversity arrays technology. 相似文献
105.
JONATHAN A. TODD ELIZABETH M. HARPER 《Lethaia: An International Journal of Palaeontology and Stratigraphy》2011,44(2):214-222
Todd, JA. & Harper, EM. 2011: Stereotypic boring behaviour inferred from the earliest known octopod feeding traces: Early Eocene, southern England. Lethaia, Vol. 44, pp. 214–222. A bulk sample of 267 disarticulated valves of the bivalve Venericor clarendonensis (Wood) collected from the Lower Eocene London Clay (southern UK) yielded 38 individuals that had been perforated by small drill holes (0.70–2.14 mm in outer diameter). These drill holes had more or less circular plan views, with slightly irregular openings, and taper as they pass through the valve, conforming to the ichnotaxon Oichnus simplex Bromley. They show stereotypic positioning, being concentrated in the posterior region on the prey, moreover there is remarkable preference for perforating the sites of muscle attachment (principally the posterior adductor). We consider the most likely culprits to be octopods. As such these are the oldest octopod drill holes yet recorded. They provide the only evidence of these important top predators in this shallow marine community and also demonstrate that the sophisticated predatory behaviour shown by modern octopods had been evolved by at least the Early Eocene. □Eocene, octopod behaviour, Oichnus, stereotypic boring. 相似文献
106.
FRANCESCA GHERARDI KENNETH M. MAVUTI NIC PACINI ELENA TRICARICO DAVID M. HARPER 《Freshwater Biology》2011,56(8):1567-1578
1. Since avoiding predation can compromise animal fitness, prey are expected to respond to different predator species with an intensity appropriate to the level of risk. In fresh waters, the threat of predation is typically assessed by chemical cues, in particular by odours released by either injured/disturbed conspecifics (conspecific alarm odour) or predators (predator odours). Here, we used the most widely distributed crayfish in the world, the invasive North American Procambarus clarkii, to investigate the relative effectiveness of odours emitted by fish predators compared with conspecific alarm odour. We also tested whether P. clarkii is able to discriminate between fish predators of which it has ‘experience’ (either recent, via introduction to the same water body, or old, by sharing a native range), as well as between fish predators that pose low or high risk. 2. The study was carried out on introduced populations of P. clarkii from two sites, characterised by different fish assemblages: the Malewa River (a tributary of Lake Naivasha, Kenya) and Lake Trasimeno (Italy). Laboratory experiments consisted of three sequential phases (‘water’, ‘food’ and ‘smell’ phases) and five treatments. Treatments differed in the odour presented during the smell phase, i.e. no odour (plain water) and odours from either injured conspecifics or three fish species per site. Crayfish from the Malewa River population were confronted with the odours of largemouth bass (Micropterus salmoides), common carp (Cyprinus carpio) and tilapia (Tilapia zillii) (all introduced to Lake Naivasha but absent from the Malewa River), and those from the Lake Trasimeno population with the odours of the introduced largemouth bass and carp and the native chub (Squalius cephalus). Largemouth bass is the only predator that imposes a high risk to crayfish, and it also shares its native range with P. clarkii. We analysed the time spent by crayfish feeding, in locomotion and in adopting a raised or lowered posture. A reduction in the time spent feeding and in locomotion, and an increase in the time spent in the lowered posture were considered to indicate alarm. 3. Crayfish from both populations responded with a more pronounced reduction in feeding to conspecific alarm odour rather than to predator odours. Crayfish from the Malewa River reacted with the same intensity to the odours of the three fish species tested, whereas, in Lake Trasimeno, the odour of largemouth bass was significantly more threatening than the odours of the other two species. 4. Procambarus clarkii seems to perceive a general fish odour that alerts it to possible predation risk without the need of either a direct recent experience or via sharing a common native range. However, where they coexist with fish, crayfish become able to distinguish among species, adapting the intensity of their response to the effective risk. Our results confirm the relatively high learning capacity of P. clarkii reported in previous studies and suggest the existence of mechanisms that make predator recognition particularly efficient in this extraordinarily successful invader. 相似文献
107.
108.
"Wild Capitalism" and "Ecocolonialism": A Tale of Two Rivers 总被引:1,自引:0,他引:1
KRISTA HARPER 《American anthropologist》2005,107(2):221-233
The development and pollution of two rivers, the Danube and Tisza, have been the site and subject of environmental protests and projects in Hungary since the late 1980s. Protests against the damming of the Danube rallied opposition to the state socialist government, drawing on discourses of national sovereignty and international environmentalism. The Tisza suffered a major environmental disaster in 2000, when a globally financed gold mine in Romania spilled thousands of tons of cyanide and other heavy metals into the river, sending a plume of pollution downriver into neighboring countries. In this article, I examine the symbolic ecologies that emerged in the two moments of environmental protest, as well as Hungarian activists' reflections on the changing political ecology of the region in their discourses of "ecocolonialism" ( ökógyarmatosítás ) and "wild capitalism" ( vadkapitaliszmus ). 相似文献
109.
J Roberto TRUJILLO Gilberto JARAMILLO-RANGEL Marta ORTEGA-MARTINEZ Augusto C PENALVA de OLIVEIRA Jose E VIDAL Joseph BRYANT Robert C GALLO 《Cell research》2005,(Z1)
INTRODUCTION AND NEUROEPIDEMIO- LOGY OF HIV/AIDS AIDS was first recognized as a new and distinct clini- cal entity in 1981 [1] and the HIV-1 as their casual agent in 1983 [2]. Since then, the HIV/AIDS epidemic has reached epidemic proportions with a total accumulative number of more than 60 million people, according to the Joint United Nations Programme on HIV/AIDS (UNAIDS) and WHO. The extensive spread of HIV-1 epidemics in Asia was not appreciated in the 1980s,… 相似文献
110.
Cynipid galls: insect-induced modifications of plant development create novel plant organs 总被引:2,自引:0,他引:2
L. J. HARPER K. SCHÖNROGGE† K. Y. LIM P. FRANCIS & C. P. LICHTENSTEIN 《Plant, cell & environment》2004,27(3):327-335
Cynipid gall formation is achieved by an insect–plant interaction whereby cynipid gallwasps redirect host‐plant development to form novel structures to protect and nourish the developing larvae. Work was carried out to investigate the molecular mechanisms involved in this interaction, and extend the understanding of plant tissue development. Cytological changes of the inner‐gall tissue throughout the development of several gall species was investigated and the developmental stages of gall formation defined, to reveal two different patterns of development followed by the galls tested. Fluorescent in situ hybridization demonstrated many of the inner‐gall cells to be polytenized. Comparisons between inner‐gall and non‐gall tissue protein signatures by Schönrogge et al. (Plant, Cell and Environment 23, 215–222, 2000) have demonstrated the variation between gall and non‐gall protein signatures, and identified a number of inner‐gall proteins. Further analysis of one of these inner‐gall proteins involved in lipid synthesis, putative biotin carboxyl carrier protein (BCCP), revealed differential expression throughout development, and showed this expression to be concentrated in the inner‐gall tissue in all the gall species tested. 相似文献