• Field geographies

      Abbott, Dina; University of Derby (Elsevier, 2012-05-29)
      Epistemological discourses such as those that have emerged from women’s studies (particularly feminism) and development studies have, however, shown geographers that there is a need to challenge the power assumptions embedded in the whole process of research, including methodological choices that can include or exclude. By tracing these discourses and using examples from these two disciplines, this article demonstrates how contemporary geography has taken on board some of the new methodological approaches that have thus transpired. In turn, this has enriched geographical enquiry, which is now, much as the subject itself, seen as a social construct requiring critical reflection and challenge.
    • First detection of a highly invasive freshwater amphipod Crangonyx floridanus (Bousfield, 1963) in the United Kingdom.

      Mauvisseau, Quentin; Davy-Bowker, John; Bryson, David; Souch, Graham; Burian, Alfred; Sweet, Michael J.; University of Derby; Surescreen Scientifics Ltd; Freshwater Biological Association; Natural History Museum (Regional Euro-Asian biological Invasions Centre, 2018-12-05)
      The freshwater gammarid, Crangonyx floridanus, originates from North America but has invaded and subsequently spread rapidly throughout Japan. We provide here the first genetic and microscopic evidence that C. floridanus has now also reached the United Kingdom. We found this species in two locations separated by more than 200 km (Lake Windermere in the North of the UK and Smestow Brook, West Midlands). The current distribution of C. floridanus is currently unknown, however, both sites are well connected to other river and canal systems. Therefore, the chance of further spread is high. Genetic analyses of C. floridanus indicate that British inland waters are colonised by the same lineage, which invaded Japan. We recommend further work to assess the distribution of this species and its impact on the local fauna and flora.
    • The floater's dilemma: use of space by wild solitary Azara's owl monkeys, Aotus azarae , in relation to group ranges

      Huck, Maren; Fernández-Duque, Eduardo; University of Derby; Yale University (Elsevier, 2017-03-26)
      The fate and behaviour of animals that leave their natal group (‘floaters’) is usually poorly understood, which can limit the understanding of a species' population dynamics. Attempted immigrations can have serious negative effects on residents who therefore may forcibly reject intruders. Consequently, floaters face a dilemma: they need to leave their natal range to find a breeding territory while trying to avoid potentially lethal rejections from established groups. To examine the hypothesis that floating Azara's owl monkeys avoid established groups temporally, we compared time-matched locations of floaters and groups with randomly selected distances. To examine the hypothesis that floaters avoid established groups spatially, we compared the utilization distribution overlap indices (UDOIs) for core areas of floaters and groups with randomly expected UDOIs. Based on average home range sizes and areas of overlap between floaters, we estimated the floater density in the study area to be 0.2e0.5 per group. The temporal avoidance hypothesis was not supported, since time-matched distances were smaller than distances of random locations, and not larger as predicted under this hypothesis. The spatial avoidance hypothesis, in contrast, was supported, with smaller UDOIs for core ranges than predicted. In conclusion, solitary owl monkeys seem to solve the floater's dilemma by trying to stay in relatively close proximity to groups while still avoiding their core ranges. Floaters thus maximize the number of groups with which they have contact, while being able to leave a group's territory quickly if detected by residents. While no marked sex differences in patterns were detected, there was a strong stochastic element to the number of floaters of a particular sex, thus resulting in a locally uneven operational sex ratio. This, in turn, can have important consequences for various aspects of the population dynamics.
    • Fostering effective international collaboration for marine science in small island states

      Alexander, Steven M.; Kritzer, Jacob P.; Sweet, Michael J.; Johnson, Ayana Elizabeth; Amargós, Fabian P.; Smith, Nicola S.; Peterson, Angelie M.; Hind, Edward; Green, Stephanie; University of Derby (Frontiers, 2015-10-21)
    • Free amino acids as phagostimulants in cricket nuptial gifts: support for the 'Candymaker' hypothesis

      Warwick, Stuart; Vahed, Karim; Raubenheimer, David; Simpson, Stephen, J.; University of Oxford; University of Derby (The Royal Society, 2009-01-20)
      Nuptial gifts that are manufactured by the male are found in numerous insect species and some spiders, but there have been very few studies of the composition of such gifts. If, as has been proposed recently, nuptial gifts represent sensory traps, males will be selected to produce gifts that are attractive to females but such gifts will not necessarily provide the female with nutritional benefits (the 'Candymaker' hypothesis). We examined the free amino acid content of the spermatophylax of the cricket Gryllodes sigillatus (Orthoptera: Gryllidae) using high performance liquid chromatography (HPLC). The spermatophylax (dry weight) consisted of approximately 7 per cent free amino acids. The free amino acid composition was highly imbalanced, with a low proportion of essential amino acids (18.7%) and a high proportion of proline and glycine. The main free amino acids found in the spermatophylax appeared to act as phagostimulants: the duration of feeding on artificial gels by females was positively related to the free amino acid content of the gels. The results therefore suggest that males use free amino acids to 'sweeten' a relatively low-value food item. A possible function of glycine in inhibiting female movement is also proposed.
    • The function of nuptial feeding in insects: a review of empirical studies

      Vahed, Karim; University of Derby (Wiley, 1998)
      Nuptial feeding encompasses any form of nutrient transfer from the male to the female during or directly after courtship and/or copulation. In insects, nuptial gifts may take the form of food captured or collected by the male, parts, or even the whole of the male's body, or glandular products of the male such as salivary secretions, external glandular secretions, the spermatophore and substances in the ejaculate. Over the past decade, there has been considerable debate over the current function of nuptial feeding in insects. This debate has centred on the issue of whether nuptial gifts function as paternal investment (i.e. function to increase the fitness and/or number of the gift-giving male's own offspring) or as mating effort (i.e. function to attract females, facilitate coupling, and/or to maximize ejaculate transfer), although the two hypotheses are not mutually exclusive. In the present article, evidence for the potential of nuptial gifts to function as either paternal investment, mating effort, or both is reviewed for each form of nuptial feeding in each insect taxon for which sufficient data are available. Empirical evidence suggests that many diverse forms of nuptial feeding in different insect taxa function, at least in part, as mating effort. For example, nuptial prey and salivary masses in the Mecoptera, regurgitated food in Drosophila (Diptera), hind-wing feeding in Cyphoderris (Orthoptera) and the secretion of the male's cephalic gland in Neopyrochroa (Coleoptera) and Zorotypus (Zoraptera) appear to function to entice females to copulate and/or to facilitate coupling. Nuptial prey and salivary masses in the Mecoptera also appear to function to maximize ejaculate transfer (which is also a form of mating effort), as do nuptial prey in Empis (Diptera), external glandular secretions in Oecanthus and Allonemobius (Orthoptera) and the spermatophylax in gryllids and tettigoniids (Orthoptera). Large spermatophores in, for example, the Lepidoptera and Coleoptera, also appear to be maintained by selection on the male to maximize ejaculate transfer and thereby counter the effects of sperm competition. In contrast to the large amount of evidence in support of the mating effort hypothesis, there is a relative lack of good evidence to support the paternal investment hypothesis. Certain studies have demonstrated an increase in the weight and/or number of eggs laid as a result of the receipt of larger gifts, or a greater number of gifts, in tettigoniids, gryllids, acridids, mantids, bruchid beetles, drosophilids and lepidopterans. However, virtually all of these studies (with the possible exception of studies of the spermatophylax in tettigoniids) have failed to control adequately for hormonal substances in the ejaculate that are known to affect female reproductive output. Furthermore, in at least four tettigoniids (but not in the case of two species), three lepidopterans, a drosophilid and probably also bruchid beetles and bittacids, evidence suggests that the male has a low probability of fertilising the eggs that stand to benefit from his nuptial gift nutrients. Therefore, the hypothesis that paternal investment might account for the function of nuptial gifts in general is not supported.
    • The function of strategic tree selectivity in the chemical signalling of brown bears

      Clapham, Melanie; Nevin, Owen T.; Ramsey, Andrew; Rosell, Frank; University of Cumbria (2013)
    • Functional equivalence of grasping cerci and nuptial food gifts in promoting ejaculate transfer in katydids.

      Vahed, Karim; Gilbert, James D. J.; Barrientos-Lozano, Ludivina; Weissman, David; University of Derby; Department of Biological and Forensic Sciences; College of Life and Natural Sciences; University of Derby; Kedleston Rd Derby DE22 1GB United Kingdom; University of Sussex; John Maynard Smith Building; Falmer Brighton BN1 9QG United Kingdom; Department of Entomology; California Academy of Sciences; San Francisco California 94118; Instituto Tecnológico de Cd. Victoria; Boulevard Emilio Portes Gil No. 1301, Cd. Victoria; Tamaulipas 87010 México (Wiley, 2014-05-21)
      The function of nuptial gifts has generated longstanding debate. Nuptial gifts consumed during ejaculate transfer may allow males to transfer more ejaculate than is optimal for females. However, gifts may simultaneously represent male investment in offspring. Evolutionary loss of nuptial gifts can help elucidate pressures driving their evolution. In most katydids (Orthoptera: Tettigoniidae), males transfer a spermatophore comprising two parts: the ejaculate-containing ampulla and the spermatophylax-a gelatinous gift that females eat during ejaculate transfer. Many species, however, have reduced or no spermatophylaces and many have prolonged copulation. Across 44 katydid species, we tested whether spermatophylaces and prolonged copulation following spermatophore transfer are alternative adaptations to protect the ejaculate. We also tested whether prolonged copulation was associated with (i) male cercal adaptations, helping prevent female disengagement, and (ii) female resistance behavior. As predicted, prolonged copulation following (but not before) spermatophore transfer was associated with reduced nuptial gifts, differences in the functional morphology of male cerci, and behavioral resistance by females during copulation. Furthermore, longer copulation following spermatophore transfer was associated with larger ejaculates, across species with reduced nuptial gifts. Our results demonstrate that nuptial gifts and the use of grasping cerci to prolong ejaculate transfer are functionally equivalent.
    • Fundamental questions and applications of sclerochronology: Community-defined research priorities.

      Trofimova, Tamara; Alexandroff, Stella; Mette, Madelyn; Tray, Elizabeth; Butler, Paul; Campana, Steven; Harper, Elizabeth; Johnson, Andrew; Morrongiello, John; Peharda, Melita; et al. (Elsevier, 2020-09-09)
      Horizon scanning is an increasingly common strategy to identify key research needs and frame future agendas in science. Here, we present the results of the first such exercise for the field of sclerochronology, thereby providing an overview of persistent and emergent research questions that should be addressed by future studies. Through online correspondence following the 5th International Sclerochronology Conference in 2019, participants submitted and rated questions that addressed either knowledge gaps or promising applications of sclerochronology. An initial list of 130 questions was compiled based on contributions of conference attendees and reviewed by expert panels formed during the conference. Herein, we present and discuss the 50 questions rated to be of the highest priority, determined through an online survey distributed to sclerochronology community members post the conference. The final list (1) includes important questions related to mechanisms of biological control over biomineralization, (2) highlights state of the art applications of sclerochronological methods and data for solving long-standing questions in other fields such as climate science and ecology, and (3) emphasizesthe need for common standards for data management and analysis. Although research priorities are continually reassessed, our list provides a roadmap that can be used to motivate research efforts and advance sclerochronology towardnew, and more powerful, applications.
    • Funding begets biodiversity

      Ahrends, Antje; Burgess, Neil D.; Gereau, Roy E.; Marchant, Rob; Bulling, Mark T.; Lovett, Jon C.; Platts, Philip J.; Kindemba, Victoria Wilkins; Owen, Nisha; Fanning, Eibleis; et al. (2013-05-24)
      Aim  Effective conservation of biodiversity relies on an unbiased knowledge of its distribution. Conservation priority assessments are typically based on the levels of species richness, endemism and threat. Areas identified as important receive the majority of conservation investments, often facilitating further research that results in more species discoveries. Here, we test whether there is circularity between funding and perceived biodiversity, which may reinforce the conservation status of areas already perceived to be important while other areas with less initial funding may remain overlooked. Location  Eastern Arc Mountains, Tanzania. Methods  We analysed time series data (1980–2007) of funding (n = 134 projects) and plant species records (n = 75,631) from a newly compiled database. Perceived plant diversity, over three decades, is regressed against funding and environmental factors, and variances decomposed in partial regressions. Cross-correlations are used to assess whether perceived biodiversity drives funding or vice versa. Results  Funding explained 65% of variation in perceived biodiversity patterns – six times more variation than accounted for by 34 candidate environmental factors. Cross-correlation analysis showed that funding is likely to be driving conservation priorities and not vice versa. It was also apparent that investment itself may trigger further investments as a result of reduced start-up costs for new projects in areas where infrastructure already exists. It is therefore difficult to establish whether funding, perceived biodiversity, or both drive further funding. However, in all cases, the results suggest that regional assessments of biodiversity conservation importance may be biased by investment. Funding effects might also confound studies on mechanisms of species richness patterns. Main conclusions  Continued biodiversity loss commands urgent conservation action even if our knowledge of its whereabouts is incomplete; however, by concentrating inventory funds in areas already perceived as important in terms of biodiversity and/or where start-up costs are lower, we risk losing other areas of underestimated or unknown value.
    • The geochemistry and oxidation state of podiform chromitites from the mantle section of the Oman ophiolite: A review

      Rollinson, Hugh; Adetunji, Jacob; University of Derby (Elsevier, 2015-02)
      Data are presented for mantle podiform chromitites from eight localities over 350 km strike length of the Oman ophiolite. Chromitite compositions form a continuum from cr# = 0.501 to 0.769, although this conflates a number of different magmatic ‘events’. The Oman mantle chromitites record a wide range of Fe3 +/ΣFe ratios (as determined by Mössbauer spectroscopy) extending from low values (close to those of MORB) to values higher than currently found in arc magmas and calculated oxygen fugacities for the chromites are about 1.8 log units above the QFM buffer, higher than found in the MORB source. Calculated TiO2 and Al2O3 contents for the parental melts to the Oman chromitites show that they had low TiO2 contents (0.23–0.96 wt.%) but a range of Al2O3 contents (11.8–15.8 wt.%). The variable Al2O3 content implies a range of parental magma compositions, probably formed at different temperatures, and the range of TiO2 compositions indicates that some melts were modified by reaction during their transit through the mantle. The range of compositions observed is not consistent with either a MORB or Arc source but is thought to reflect a range of melts derived from a compositionally evolving source during subduction initiation in a forearc environment
    • Geographical variation in the response to nitrogen deposition in Arabidopsis lyrata petraea.

      Vergeer, Philippine; van den Berg, Leon L. J.; Bulling, Mark T.; Ashmore, Mike R.; Kunin, William E.; University of Leeds, Institute of Integrative and Comparative Biology (2008)
      The adaptive responses to atmospheric nitrogen deposition for different European accessions of Arabidopsis lyrata petraea were analysed using populations along a strong atmospheric N-deposition gradient. Plants were exposed to three N-deposition rates, reflecting the rates at the different locations, in a full factorial design. Differences between accessions in the response to N were found for important phenological and physiological response variables. For example, plants from low-deposition areas had higher nitrogen-use efficiencies (NUE) and C : N ratios than plants from areas high in N deposition when grown at low N-deposition rates. The NUE decreased in all accessions at higher experimental deposition rates. However, plants from high-deposition areas showed a limited capacity to increase their NUE at lower experimental deposition rates. Plants from low-deposition areas had faster growth rates, higher leaf turnover rates and shorter times to flowering, and showed a greater increase in growth rate in response to N deposition than those from high-deposition areas. Indications for adaptation to N deposition were found, and results suggest that adaptation of plants from areas high in N deposition to increased N deposition has resulted in the loss of plasticity.
    • Geographically conserved rates of background mortality among common reef-building corals in Lhaviyani Atoll, Maldives, versus northern Great Barrier Reef, Australia

      Pisapia, Chiara; Sweet, Michael J.; Sweatman, Hugh; Pratchett, Morgan; University of Derby (Springer Berlin Heidelberg, 2015-07-14)
      Even in the absence of major disturbances (e.g., cyclones and bleaching), corals are consistently subject to high levels of background mortality, which under-mines individual fitness and resilience of coral colonies. Most studies of coral mortality however only focus on catastrophic mortality associated with major acute disturbance events, neglecting to consider background levels of chronic mortality that have a significant influence on population structure and turnover. If, for example, there are geo-graphic differences in the prevalence of injuries and rates of background mortality, coral communities may vary in their susceptibility to acute large-scale disturbances and environmental change. This study quantified the prevalence and severity of partial mortality for four dominant and widespread coral taxa (massive Porites, encrusting Montipora, Acropora hyacinthus,and branching Pocillopora) at Lhaviyani Atoll, Maldives, and on the northern Great Barrier Reef, Australia. The prevalence and severity of sublethal injuries varied greatly among taxa, but was generally similar between locations; on the Great Barrier Reef, 99.4 % Porites colonies, 66 % of A. hyacinthus, and 64 % of Pocillopora had conspicuous injuries, compared to 92.4 % of Porites, 47.5 % of A. hyacinthus, and 44 % of Pocillopora colonies in Lhaviyani Atoll. These results suggest that background rates of mortality and injury, and associated resilience of coral populations and communities to large-scale disturbances, are conserved at large geo-graphic scales, though adjacent colonies can have markedly different injury regimes, likely to lead to strong intraspecific variation in colony fitness and resilience.
    • Geology of Caphouse Colliery, Wakefield, Yorkshire, UK

      Davies-Vollum, K. Siân; Guion, Paul. D.; Knight, John. A.; Smith, Andrew; University of Derby (Geological Society of London, 2016-09-28)
      The National Coal Mining Museum in West Yorkshire affords a rare opportunity for the public to visit a former colliery (Caphouse) and experience at first hand the geology of a mine. The geology at the museum can be seen via the public tour, limited surface outcrop and an inclined ventilation drift, which provides the best geological exposure and information. The strata encountered at the site are c. 100 m thick and are of latest Langsettian (Pennsylvanian) age. The ventilation drift intersects several coal seams (Flockton Thick, Flockton Thin, Old Hards, Green Lane and New Hards) and their associated roof rocks and seatearths. In addition to exposures of bedrock, recent mineral precipitates of calcium carbonates, manganese carbonates and oxides, and iron oxyhydroxides can be observed along the drift, and there is a surface exposure of Flockton Thick Coal and overlying roof strata. The coals and interbedded strata were deposited in the Pennine Basin in a fluvio-lacustrine setting in an embayment distant from the open ocean with limited marine influence. A lacustrine origin for mudstone roof rocks of several of the seams is supported by the incidence of non-marine bivalves and fossilized fish remains whilst the upper part of the Flockton Thick Coal consists of subaqueously deposited cannel coal. The mudstones overlying the Flockton Thick containing abundant non-marine bivalves are of great lateral extent, indicating a basin-wide rise of base level following coal deposition that may be compared with a non-marine flooding surface.
    • Glacial history of Mt Chelmos, Peloponnesus, Greece

      Pope, R. J.; Hughes, P. D.; Skourtsos, E.; University of Derby; University of Manchester; University of Athens (Geological Society of London, 2015-11-11)
      Mount Chelmos in the Peloponnesus was glaciated by a plateau ice field during the most extensive Pleistocene glaciation. Valley glaciers radiated out from an ice field centred over the central plateau of the massif. The largest glaciations are likely to be Middle Pleistocene in age. Smaller valley and cirque glaciers formed later and boulders on the moraines of these glacial phases have been dated using 36 Cl terrestrial cosmogenic nuclide exposure dating. These ages indicate a Late Pleistocene age with glacier advance/stabilisation at 40-30 ka, glacier retreat at 23-21 ka and advance/stabilisation at 13-10 ka. This indicates that the glacier maximum of the last cold stage occurred during Marine Isotope Stage (MIS) 3, several thousand years before the global Last Glacial Maximum (LGM; MIS 2) . The last phase of moraine building occurred at the end of the Pleistocene, possibly during the Younger Dryas.
    • Global Invasive Potential of 10 Parasitic Witchweeds and Related Orobanchaceae

      Mohamed, Kamal I.; Papes, Monica; Williams, Richard; Benz, Brett W.; Peterson, A. Townsend; Department of Biology, Oswego State University of New York, Oswego, NY 13126 USA; Natural History Museum and Biodiversity Research Center, The University of Kansas, Lawrence, KS 66045 USA. (Royal Swedish Academy of Sciences, 2006-09-01)
      The plant family Orobanchaceae includes many parasitic weeds that are also impressive invaders and aggressive crop pests with several specialized features (e.g. microscopic seeds, parasitic habits). Although they have provoked several large-scale eradication and control efforts, no global evaluation of their invasive potential is as yet available. We use tools from ecological niche modeling in combination with occurrence records from herbarium specimens to evaluate the global invasive potential of each of 10 species in this assemblage, representing several of the worst global invaders. The invasive potential of these species is considerable, with all tropical and subtropical countries, and most temperate countries, vulnerable to invasions by one or more of them.
    • Global patterns of bioturbation intensity and mixed depth of marine soft sediments

      Teal, L. R.; Bulling, Mark T.; Parker, E. R.; Solan, Martin (2013-06-11)
      ABSTRACT: The importance of bioturbation in mediating biogeochemical processes in the upper centimetres of oceanic sediments provides a compelling reason for wanting to quantify in situ rates of bioturbation. Whilst several approaches can be used for estimating the rate and extent of bioturba- tion, most often it is characterized by calculating an intensity coefficient (D b ) and/or a mixed layer depth (L). Using measures of D b (n = 447) and L (n = 784) collated largely from peer-reviewed litera- ture, we have assembled a global database and examined patterns of both L and D b . At the broadest level, this database reveals that there are considerable gaps in our knowledge of bioturbation for all major oceans other than the North Atlantic, and almost universally for the deep ocean. Similarly, there is an appreciable bias towards observations in the Northern Hemisphere, particularly along the coastal regions of North America and Europe. For the assembled dataset, we find large discrepancies in estimations of L and D b that reflect differences in boundary conditions and reaction properties of the methods used. Tracers with longer half-lives tend to give lower D b estimates and deeper mixing depths than tracers with shorter half-lives. Estimates of L based on sediment profile imaging are significantly lower than estimates based on tracer methods. Estimations of L, but not D b , differ between biogeographical realms at the global level and, at least for the Temperate Northern Atlantic realm, also at the regional level. There are significant effects of season irrespective of location, with higher activities (D b ) observed during summer and deeper mixing depths (L) observed during autumn. Our evaluation demonstrates that we have reasonable estimates of bioturbation for only a limited set of conditions and regions of the world. For these data, and based on a conservative global mean (±SD) L of 5.75 ± 5.67 cm (n = 791), we calculate the global volume of bioturbated sediment to be >20 700 km 3 . Whilst it is clear that the role of benthic invertebrates in mediating global ecosystem processes is substantial, the level of uncertainty at the regional level is unacceptably high for much of the globe.
    • A global synthesis of plant extinction rates in urban areas.

      Hahs, Amy K.; McDonnell, Mark J.; McCarthy, Michael A.; Vesk, Peter A.; Corlett, Richard T.; Norton, Briony, A.; Clemants, Steven E.; Duncan, Richard P.; Thompson, Ken; Schwartz, Mark W.; et al. (Wiley, 2009-10-13)
      Plant extinctions from urban areas are a growing threat to biodiversity worldwide. To minimize this threat, it is critical to understand what factors are influencing plant extinction rates. We compiled plant extinction rate data for 22 cities around the world. Two‐thirds of the variation in plant extinction rates was explained by a combination of the city’s historical development and the current proportion of native vegetation, with the former explaining the greatest variability. As a single variable, the amount of native vegetation remaining also influenced extinction rates, particularly in cities > 200 years old. Our study demonstrates that the legacies of landscape transformations by agrarian and urban development last for hundreds of years, and modern cities potentially carry a large extinction debt. This finding highlights the importance of preserving native vegetation in urban areas and the need for mitigation to minimize potential plant extinctions in the future.
    • Green roof and ground-level invertebrate communities are similar and are driven by building height and landscape context

      Dromgold, Jacinda R; Threlfall, Caragh G; Norton, Briony, A.; Williams, Nicholas S G; University of Melbourne, Melbourne, Australia; University of Derby (Oxford University Press (OUP), 2020-01-30)
      Green roofs are increasingly promoted for urban biodiversity conservation, but the value of these novel habitats is uncertain. We aimed to test two hypotheses: (i) green roofs can support comparable invertebrate family and order richness, composition and abundances to ground-level habitats and (ii) green roofs planted with native species from local habitats will support a richer invertebrate community at family and order level than other green roofs. We sampled the invertebrate community on green roofs dominated by native grassland or introduced succulent species in Melbourne, Australia, and compared these to the invertebrate community in ground-level sites close by, and sites with similar vegetation types. The only significant differences between the invertebrate communities sampled on green roofs and ground-level habitats were total abundance and fly family richness, which were higher in ground-level habitats. Second hypothesis was not supported as invertebrate communities on green roofs supporting a local vegetation community and those planted with introduced Sedum and other succulents were not detectably different at family level. The per cent cover of green space surrounding each site was consistently important in predicting the richness and abundance of the invertebrate families we focussed on, while roof height, site age and size were influential for some taxa. Our results suggest that invertebrate communities of green roofs in Melbourne are driven largely by their surrounding environment and consequently the effectiveness of green roofs as invertebrate habitat is highly dependent on location and their horizontal and vertical connection to other habitats.
    • Grooming relationships between breeding females and adult group members in cooperatively breeding moustached tamarins (Saguinus mystax)

      Löttker, Petra; Huck, Maren; Zinner, Dietmar P.; Heymann, Eckhard W.; Department of Behavioral Ecology and Sociobiology, German Primate Centre; Department of Cognitive Ethology, German Primate Centre, Germany (2007)
      Grooming is the most common form of affiliative behavior in primates that apart from hygienic and hedonistic benefits offers important social benefits for the performing individuals. This study examined grooming behavior in a cooperatively breeding primate species, characterized by single female breeding per group, polyandrous matings, dizygotic twinning, delayed offspring dispersal, and intensive helping behavior. In this system, breeding females profit from the presence of helpers but also helpers profit from staying in a group and assisting in infant care due to the accumulation of direct and indirect fitness benefits. We examined grooming relationships of breeding females with three classes of partners (breeding males, potentially breeding males, (sub)adult non-breeding offspring) during three reproductive phases (post-partum ovarian inactivity, ovarian activity, pregnancy) in two groups of wild moustached tamarins (Saguinus mystax). We investigated whether grooming can be used to regulate group size by either ‘‘pay-for-help’’ or ‘‘pay-to-stay’’ mechanisms. Grooming of breeding females with breeding males and nonbreeding offspring was more intense and more balanced than with potentially breeding males, and most grooming occurred during the breeding females’ pregnancies. Grooming was skewed toward more investment by the breeding females with breeding males during the phases of ovarian activity, and with potentially breeding males during pregnancies. Our results suggest that grooming might be a mechanism used by female moustached tamarins to induce mate association with the breeding male, and to induce certain individuals to stay in the group and help with infant care.