The Department of Biological Sciences has an expanding research base, which, in addition to providing leading researchers of national and international standing in these areas, most importantly underpins the delivery of teaching. Research in Biological Sciences at Chester can be divided into three broad groups of expertise, namely Animal Behaviour and Conservation, Food Nutrition and Health, and Stress and Disease.

Recent Submissions

  • New Evidence of an Additional Population of the White-naped Mangabey Cercocebus lunulatus in Western Ghana

    Stanley, Christina R; Geary, Matthew; Nolan, Ryan; Welsh, Adam; Hartley, Matthew; Dempsey, Andrea; Mono, Joseph Cudjoe; Osei, David; University of Chester; West African Primate Conservation Action; The Forestry Commission of Ghana; Zoo and Wildlife Solutions Ltd (IUCN/SSC Primate Specialist Group, 2019)
    The white-naped mangabey Cercocebus lunulatus is severely threatened by logging, mining, and hunting. In the last decade, wild populations have been confirmed in just three forested areas in Ghana and a handful of sites in neighboring Côte d’Ivoire and Burkina Faso. Sightings of this species were recently reported in a fourth area in Ghana, the Cape Three Points Forest Reserve, a forest patch in western Ghana, 60 km from the nearest recorded wild population, which is in the Ankasa Conservation Area. We deployed 14 camera traps across 21 different locations throughout the reserve, with the intention of confirming the presence of this species. Images of the white-naped mangabey were captured at four locations, confirming the existence of a fourth sub-population of this species in Ghana and providing only the second-ever photograph of a wild member of this species in the country. We observed evidence of numerous illegal anthropogenic activities in the reserve, which threaten these mangabeys, and we make recommendations for the protection of the reserve, essential for the conservation of this highly endangered species.
  • CD271-selected mesenchymal stem cells from adipose tissue enhance cartilage repair and are less angiogenic than plastic adherent mesenchymal stem cells.

    Kohli, Nupur; Al-Delfi, Ibtesam R T; Snow, Martyn; Sakamoto, Takumi; Miyazaki, Tsuyoshi; Nakajima, Hideaki; Uchida, Kenzo; Johnson, William E B (2019-02-28)
    CD271 is a marker of bone marrow MSCs with enhanced differentiation capacity for bone or cartilage repair. However, the nature of CD271+ MSCs from adipose tissue (AT) is less well understood. Here, we investigated the differentiation, wound healing and angiogenic capacity of plastic adherent MSCs (PA MSCs) versus CD271+ MSCs from AT. There was no difference in the extent to which PA MSCs and CD271+ MSCs formed osteoblasts, adipocytes or chondrocytes in vitro. In contrast, CD271+ MSCs transplanted into athymic rats significantly enhanced osteochondral wound healing with reduced vascularisation in the repair tissue compared to PA MSCs and control animals; there was little histological evidence of mature articular cartilage formation in all animals. Conditioned medium from CD271+ MSC cultures was less angiogenic than PA MSC conditioned medium, and had little effect on endothelial cell migration or endothelial tubule formation in vitro. The low angiogenic activity of CD271+ MSCs and improved early stage tissue repair of osteochondral lesions when transplanted, along with a comparable differentiation capacity along mesenchymal lineages when induced, suggests that these selected cells are a better candidate than PA MSCs for the repair of cartilaginous tissue.
  • Isoform-specific Ras signaling is growth factor dependent

    Hood, Fiona; Klinger, Bertram; Newlaczyl, Anna; Sieber, Anja; Dorel, Mathurin; Oliver, Simon; Coulsen, Judy; Bluthgen, Nils; Prior, Ian; University of Liverpool; Universitätsmedizin Berlin; University of Chester (ASCB, 2019-02-20)
    HRAS, NRAS and KRAS isoforms are almost identical proteins that are ubiquitously expressed and activate a common set of effectors. In vivo studies have revealed that they are not biologically redundant; however, the isoform-specificity of Ras signaling remains poorly understood. Using a novel panel of isogenic SW48 cell lines endogenously expressing wild type or G12V mutated activated Ras isoforms we have performed a detailed characterization of endogenous isoform-specific mutant Ras signaling. We find that despite displaying significant Ras activation, the downstream outputs of oncogenic Ras mutants are minimal in the absence of growth factor inputs. The lack of mutant KRAS-induced effector activation observed in SW48 cells appears to be representative of a broad panel of colon cancer cell lines harboring mutant KRAS. For MAP kinase pathway activation in KRAS mutant cells, the requirement for co-incident growth factor stimulation occurs at an early point in the Raf activation cycle. Finally, we find that Ras isoform-specific signaling was highly context dependent and did not conform to the dogma derived from ectopic expression studies.
  • Integrating role-play with case study and carbon footprint monitoring: A transformative approach to enhancing learners' behaviour for a more sustainable environment

    Oliver, Simon; University of Chester (Look Acedemic Publishers, 2016-05-01)
    Educators have long used role-play to encourage a significant shift in learner perspective, and the social and cognitive benefits of this active learning tool are well documented. Although the use of role-play has been encouraged as a transformative approach to challenge the worldview of individual learners in the context of environmental education, the efficacy of its application as a direct means to enhance learners’ behavior towards the environment has not been previously investigated. In this study role-play simulations were integrated with case study to expose learners to some of the socioscientific issues that typically arise from environmental debate. Learners were separated into groups representing the interests of parties that typically negotiate environmental affairs in real world scenarios (conservationists, scientists, politicians, NGOs, stakeholders), and tasked with preparing role-play simulations using a variety of flipped learning techniques. Learners’ carbon footprints were monitored pre and post intervention, and CO2 emission scores were used as a proxy for their behaviour towards the environment. Five role-play simulations were run overall. These were integrated with case studies associated with fisheries issues, and climate change. Anonymous participant surveys indicated that learners responded positively to the intervention, and participants’ CO2 emission scores improved significantly (T1,59 = 2.723, p = 0.009). In the context of environmental sciences, learners that engage in the integrated role-play and case study approach may benefit from flipped learning techniques to prepare their simulations, and gain confidence from self-actualising moments of achievement when they realise an improvement in their environmental behaviour.
  • Risk and resilience: high stakes for sharks making transjurisdictional movements to use a conservation area.

    Oliver, Simon Peter; Grothues, Thomas; Williams, Amie; Cerna, Voltaire; Silvosa, Medel; Cases, Gary; Reed, Matthew; Christopher, Simon; University of Chester; Rutgers University Marine Field Station; Scotish National Heritage; The Thresher Shark Research and Conservation Project; Divelink Cebu; Evolution Dive Resort; Scubazoo (Elsevier, 2019-02)
    Oceanic sharks are vulnerable to overexploitation due to their life-history strategies, and declines in their populations are well documented. While it is clear that pelagic sharks are often subjected to uncontrolled fishing for their meat and valuable fins, a lack of empirical knowledge, and transboundary jurisdictional issues have stalled many initiatives to protect them in the wild. Alopiids, including pelagic thresher sharks, are important to Asian fisheries, but the extent to which they are exploited in the Philippines is unknown. We fitted 14 pelagic thresher sharks with acoustic tags, and monitored their fine scale lateral movements near a seamount in the Central Visayas where their regular occurrence is prized as a tourism enterprise. Pelagic thresher sharks used a specific corridor to move away from the seamount after early morning visits to cleaner wrasse. Long range dispersals occurred at a mean rate of 3.79 ± 1.43 km h-1 and were attributed to foraging behavior. Daily foraging expeditions led pelagic thresher sharks to potentially venture across the jurisdictional waters of five provincial territories even when they regularly returned to the seamount. Thresher sharks preferred specific locations on the seamount where they interact with cleaner fish. While the seamount offers cleaner associated services and refuge provision for these rare and elusive sharks, disconnects between habitual predator and prey localizations are likely to increase their vulnerability to pressure from large scale fisheries that operate in the area.
  • Recovery of high mountain Alpine lakes after the eradication of introduced brook trout Salvelinus fontinalis using non-chemical methods

    Tiberti, Rocco; Bogliani, Giuseppe; Brighenti, Stefano; Iacobuzio, Rocco; Liautaud, Kevin; Rolla, Matteo; von Hardenberg, Achaz; Bassano, Bruno; University of Pavia; Gran Paradiso National Park; University of Trento; Fondazione Edmund Mach; Swansea University; University of Chester (Springer, 2018-10-31)
    Fish stocking is a serious threat to originally fishless mountain lakes. We used non-chemical eradication methods (i.e. gillnetting and electrofishing) in four high mountain lakes in the Gran Paradiso National Park (Western Italian Alps) to eradicate alien brook trout Salvelinus fontinalis. Data of amphibians, macroinvertebrates, zooplankton, chlorophyll-a, nutrient concentrations, and water transparency were used as indicators of the recovery process. All treated lakes were returned to their original fishless condition in spite of their different sizes and habitat complexity, without permanent negative side-effects for native species. Several ecological indicators showed that many impacts of introduced fish can be reversed over a short time period following eradication. The present study adds to a still growing body of specialized literature on the recovery of habitats after the eradication of alien species and provides further evidence that physical eradication methods are effective and can be part of a more general strategy for the conservation of high mountain lake biota.
  • One strategy doesn’t fit all: determinants of urban adaptation in mammals

    Santini, Luca; González‐Suárez, Manuela; Russo, Danilo; Gonzalez‐Voyer, Alejandro; von Hardenberg, Achaz; Ancillotto, Leonardo; Radboud University; University of Reading; University of Napoli; Universidad Nacional Autónoma de México; University of Chester (Wiley, 2018-12-20)
    Urbanisation exposes wildlife to new challenging conditions and environmental pressures. Somemammalian species have adapted to these novel environments, but it remains unclear which char-acteristics allow them to persist. To address this question, we identified 190 mammals regularlyrecorded in urban settlements worldwide, and used phylogenetic path analysis to test hypothesesregarding which behavioural, ecological and life history traits favour adaptation to urban environ-ments for different mammalian groups. Our results show that all urban mammals produce largerlitters; whereas other traits such as body size, behavioural plasticity and diet diversity were impor-tant for some but not all taxonomic groups. This variation highlights the idiosyncrasies of theurban adaptation process and likely reflects the diversity of ecological niches and roles mammalscan play. Our study contributes towards a better understanding of mammal association tohumans, which will ultimately allow the design of wildlife-friendly urban environments and con-tribute to mitigate human-wildlife conflicts.
  • Tspan18 is a novel regulator of the Ca2+ channel Orai1 and von Willebrand factor release in endothelial cells.

    Noy, Peter J; Gavin, Rebecca L; Colombo, Dario; Haining, Elizabeth J; Reyat, Jasmeet S; Payne, Holly; Thielmann, Ina; Lokman, Adam B; Neag, Georgiana; Yang, Jing; Lloyd, Tammy; Harrison, Neale; Heath, Victoria L; Gardiner, Chris; Whitworth, Katharine M; Robinson, Joseph; Koo, Chek Z; Di Maio, Alessandro; Harrison, Paul; Lee, Steven P; Michelangeli, Francesco; Kalia, Neena; Rainger, G Ed; Nieswandt, Bernhard; Brill, Alexander; Watson, Steve P; Tomlinson, Michael G; email: m.g.tomlinson@bham.ac.uk (2018-12-20)
    Ca entry via Orai1 store-operated Ca channels in the plasma membrane is critical to cell function, and Orai1 loss causes severe immunodeficiency and developmental defects. The tetraspanins are a superfamily of transmembrane proteins that interact with specific partner proteins and regulate their trafficking and clustering. The aim of this study was to functionally characterize tetraspanin Tspan18. We show that Tspan18 is expressed by endothelial cells at several-fold higher levels than most other cell types analyzed. Tspan18-knockdown primary human umbilical vein endothelial cells have 55-70% decreased Ca mobilization upon stimulation with the inflammatory mediators thrombin or histamine, similar to Orai1-knockdown. Tspan18 interacts with Orai1, and Orai1 cell surface localization is reduced by 70% in Tspan18-knockdown endothelial cells. Tspan18 over-expression in lymphocyte model cell lines induces 20-fold activation of Ca -responsive NFAT signaling, in an Orai1-dependent manner. Tspan18-knockout mice are viable. They lose on average 6-fold more blood in a tail-bleed assay. This is due to Tspan18 deficiency in non-hematopoietic cells, as assessed using chimeric mice. Tspan18-knockout mice have 60% reduced thrombus size in a deep vein thrombosis model, and 50% reduced platelet deposition in the microcirculation following myocardial ischemia-reperfusion injury. Histamine- or thrombin-induced von Willebrand factor release from endothelial cells is reduced by 90% following Tspan18-knockdown, and histamine-induced increase of plasma von Willebrand factor is reduced by 45% in Tspan18-knockout mice. These findings identify Tspan18 as a novel regulator of endothelial cell Orai1/Ca signaling and von Willebrand factor release in response to inflammatory stimuli. [Abstract copyright: Copyright © 2018, Ferrata Storti Foundation.]
  • Recapture rates and habitat associations of White-faced Darter Leucorhinnia dubia on Fenn's and Whixall Moss, Shropshire, UK

    Davies, Rachel; von Hardenberg, Achaz; Geary, Matthew; Conservation Biology Research Group, Department of Biological Sciences, University of Chester, CH1 4BJ (British Dragonfly Society, 2018-10-01)
    Land-use change and habitat loss are important drivers of biodiversity decline at both global and local scales. To protect species from the impacts of land-use change it is important to understand the population dynamics and habitat associations across these scales. Here we present an investigation into the survival and habitat preferences of Leucorrhinia dubia at the local scale at Fenn’s and Whixall Moss, Shropshire, UK. We used mark-release-recapture methods to investigate survival and used sightings of individual dragonflies along with habitat data to investigate habitat preference. We found that survival between capture-visits was very low and that L. dubia showed a clear preference for the open moss habitat on this site. In both cases, we found that the detectability, either through sightings or recaptures, was potentially very low and suggest that this should be taken into account in future analyses. We suggest that by encouraging recorders to submit complete lists and to repeat visits to sites detectability could be easily estimated for dragonfly species and incorporating this into analyses would improve estimates fo population trends and habitat associations.
  • Chapter Ten: Handling and Restraint of Small Ruminants

    McLennan, Krista; Chapman, Stella; University of Chester; University Centre Hartpury (Wiley, 2018-01-01)
    Sheep (Ovis aries) were one of the first mammals to be domesticated by humans; however the exact timeline of events has been unclear. The use of mitochondrial DNA testing has recently made it possible to trace back the ancestry of many animals including cattle, horses, pigs and goats and evidence suggests that the number of wild progenitors for these species is limited; however, with the sheep this is not the case and it is thought that a large number of wild ancestral species and subspecies exist (Hiendleder et al. 2002). Archaeological findings have traced the sheep back to 11000 and 9000 BC in Mesopotamia, with the most common hypothesis being that Ovis aries descended from the Asiatic (Ovis orientalis) species of mouflon. Many studies have looked at the ancestry of sheep and there has been conflicting evidence with regards to the numbers of ancestors. It is now thought that three major groups of Eurasian wild sheep (mouflon, urial and argali) are the ancestors of the domestic sheep and it is these groups that are believed to have contributed to specific breeds (Hiendleder et al. 2002).
  • Chapter Twelve: Handling and Restraint of South American Camelids

    McLennan, Krista M; Chapman, Stella; University of Chester; University Centre Hartpury (Wiley, 2018-01-01)
    Members of the camelid family evolved to live in arid and mountainous areas. This chapter will focus on what are known as the New World species of camelid, whose habitat mainly covers the Andes regions of South America. Four camelids can be found in South America, namely: Guanacos (Lama guanicoe), vicunas (Lama vicugna), llamas (Lama guanicoe glama) and alpacas (Vicugna pacos). The two wild forms, the guanaco and the vicuna diverged from a common ancestor approximately two million years ago; an event unrelated to domestication. Due to hybridisation the exact process of domestication has been controversial; however, recent genetic analysis has suggested that the alpaca is the domesticated form of the vicuna and the llama is the domesticated form of the guanaco (Kadwell et al. 2001). Domestication is thought to have taken place some 6000 years ago (Wheeler, 1995) when a predominant herding economy based on llama and alpaca was established at Telarmachay (a region of the Peruvian Andes). Archaeological evidence suggests that both llamas and alpacas were part of a sacrificial rite in South American culture and were key to the expansion of the Inca Empire some 500 years ago (Bonacic, 2011). Physically (apart from size) there is little difference between the llama and alpaca, which is a result of deliberate hybridisation between the two species over the past 35 years. Whilst the alpaca and llama still play an important role in their countries of origin, they are also viewed worldwide as: pets, exotic animals, livestock, zoo animals and wild animals.
  • ‘Regurgitation and reingestion’ (R/R) in great apes: A review of current knowledge

    Hill, Sonya; University of Chester; University of Cambridge (Wiley, 2018-08-02)
    Research indicates that regurgitation and reingestion (R/R) is a relatively common behaviour in zoo-housed great apes, with most work to date carried out on Western lowland gorillas Gorilla gorilla gorilla and Chimpanzees Pan troglodytes. It is an abnormal behaviour because great apes are not anatomically adapted to regurgitate their food as part of their normal feeding processes, and because this behaviour is not seen in members of the species living freely in the wild, in conditions that would allow a full behavioural range. In this article, I give an overview of the published literature on R/R in great apes, which suggests that this behaviour is probably multifactorial and may be linked to inappropriate feeding environments (e.g. in terms of nutritional composition of the diet and/or presentation of food), and possibly also social and other factors as well. A similar behaviour to R/R, known as rumination disorder, can also occur in another great ape species, humans, in whom it is classified as a feeding and eating disorder, and there are potential consequences to people’s physical health as a result of oral acid. There have been no known studies to date to identify whether or not similar health consequences can occur in non-human great apes, but the regurgitant has been found to be significantly more acidic in gorillas than the food they ingested originally, meaning it is potentially injurious in non-human great apes. There is much that is not yet known about this behaviour and how to reduce or eliminate it when it does occur, as the research indicates that there are a range of factors involved, and these can vary by individual animal. More research into this behaviour is clearly needed to ensure that zoos and sanctuaries are providing the best possible care for these animals, and I make some suggestions for future research directions.
  • Why pain is still a welfare issue for farm animals, and how facial expression may be the answer

    McLennan, Krista; University of Chester (MDPI, 2018-08-11)
    Pain is a sensory and emotional experience that significantly affects animal welfare and has negative impacts on the economics of farming. Pain is often associated with common production diseases such as lameness and mastitis, as well as introduced to the animal through routine husbandry practices such as castration and tail docking. Farm animals are prey species which tend not to overtly express pain or weakness, making recognizing and evaluating pain incredibly difficult. Current methods of pain assessment do not provide information on what the animal is experiencing at that moment in time, only that its experience is having a long term negative impact on its behavior and biological functioning. Measures that provide reliable information about the animals’ affective state in that moment are urgently required; facial expression as a pain assessment tool has this ability. Automation of the detection and analysis of facial expression is currently in development, providing further incentive to use these methods in animal welfare assessment.
  • Comparison of Mesenchymal Stromal Cells Isolated from Murine Adipose Tissue and Bone Marrow in the Treatment of Spinal Cord Injury.

    Takahashi, Ai; Nakajima, Hideaki; Uchida, Kenzo; Takeura, Naoto; Honjoh, Kazuya; Watanabe, Shuji; Kitade, Makoto; Kokubo, Yasuo; Johnson, William E B; Matsumine, Akihiko (2018-01-01)
    The use of mesenchymal stromal cell (MSC) transplantation to repair the injured spinal cord has shown consistent benefits in preclinical models. However, the low survival rate of grafted MSC is one of the most important problems. In the injured spinal cord, transplanted cells are exposed to hypoxic conditions and exposed to nutritional deficiency caused by poor vascular supply. Also, the transplanted MSCs face cytotoxic stressors that cause cell death. The aim of this study was to compare adipose-derived MSCs (AD-MSCs) and bone marrow-derived MSCs (BM-MSCs) isolated from individual C57BL6/J mice in relation to: (i) cellular characteristics, (ii) tolerance to hypoxia, oxidative stress and serum-free conditions, and (iii) cellular survival rates after transplantation. AD-MSCs and BM-MSCs exhibited a similar cell surface marker profile, but expressed different levels of growth factors and cytokines. To research their relative stress tolerance, both types of stromal cells were incubated at 20.5% O or 1.0% O for 7 days. Results showed that AD-MSCs were more proliferative with greater culture viability under these hypoxic conditions than BM-MSCs. The MSCs were also incubated under H O -induced oxidative stress and in serum-free culture medium to induce stress. AD-MSCs were better able to tolerate these stress conditions than BM-MSCs; similarly when transplanted into the spinal cord injury region in vivo, AD-MSCs demonstrated a higher survival rate post transplantation Furthermore, this increased AD-MSC survival post transplantation was associated with preservation of axons and enhanced vascularization, as delineated by increases in anti-gamma isotype of protein kinase C and CD31 immunoreactivity, compared with the BM-MSC transplanted group. Hence, our results indicate that AD-MSCs are an attractive alternative to BM-MSCs for the treatment of severe spinal cord injury. However, it should be noted that the motor function was equally improved following moderate spinal cord injury in both groups, but with no significant improvement seen unfortunately following severe spinal cord injury in either group.
  • Activating KIR Haplotype Influences Clinical Outcome Following HLA-Matched Sibling Hematopoietic Stem Cell Transplantation.

    Heatley, S. L.; Mullighan, C. G.; Doherty, K.; O'Connor, Geraldine, M.; Hahn, U.; Szer, J.; Schwarer, A.; Bradstock, K.; Sullivan, L. C.; Bardy, P. G.; Brooks, A. G.; University of Melbourne, Melbourne, Vic, Australia; Australian Red Cross Blood Service, Adelaide, SA, Australia; St Jude Children's Research Hospital, Memphis, TN, USA; 4 Royal Adelaide and Queen Elizabeth Hospitals, SA Pathology, Adelaide, SA, Australia; Royal Melbourne Hospital, Melbourne, Vic, Australia; Alfred Hospital, Melbourne, Vic, Australia; Westmead Hospital, Sydney, NSW, Australia (Wiley, 2018-06-25)
    Natural killer cells are thought to influence the outcome of hematopoietic stem cell transplant (HSCT), impacting on relapse, overall survival, graft versus host disease and the control of infection, in part through the complex interplay between the large and genetically diverse killer immunoglobulin-like receptor (KIR) family and their ligands. This study examined the relationship between KIR gene content and clinical outcomes including the control of opportunistic infections such as cytomegalovirus in the setting of human leucocyte antigen (HLA)-matched sibling HSCT in an Australian cohort. The presence of the KIR B haplotype which contain more activating receptors in the donor, in particular centromeric B haplotype genes (Cen-B), was associated with improved overall survival of patients with acute myeloid leukemia (AML) undergoing sibling HSCT and receiving myeloablative conditioning. Donor Cen-B haplotype was also associated with reduced acute graft versus host disease grades II-IV whereas donor telomeric-B haplotype was associated with decreased incidence of CMV reactivation. In contrast, we were not able to demonstrate a reduced rate of relapse when the donor had KIR Cen-B, however relapse with a donor Cen-A haplotype was a competing risk factor to poor overall survival. Here we show that the presence of donor activating KIR led to improved outcome for the patient, potentially through reduced relapse rates and decreased incidence of acute GvHD translating to improved overall survival.
  • A call to action for climate change research on Caribbean dry forests

    Nelson, Howard, P.; Devenish-Nelson, Eleanor S.; Rusk, Bonnie L.; Geary, Matthew; Lawrence, Andrew J.; Department of Biological Sciences, University of Chester; Grenada Dove Conservation Programme, St. Georges, Grenada (Springer, 2018-04-23)
    Tropical dry forest (TDF) is globally one of the most threatened forest types. In the insular Caribbean, limited land area and high population pressure have resulted in the loss of over 60% of TDF, yet local people’s reliance on these systems for ecosystem services is high. Given the sensitivity of TDF to shifts in precipitation regimes and the vulnerability of the Caribbean to climate change, this study examined what is currently known about the impacts of climate change on TDF in the region. A systematic review (n = 89) revealed that only two studies addressed the ecological response of TDF to climate change. Compared to the rapidly increasing knowledge of the effects of climate change on other Caribbean systems and on TDF in the wider neotropics, this paucity is alarming given the value of these forests. We stress the need for long-term monitoring of climate change responses of these critical ecosystems, including phenological and hotspot analyses as priorities.
  • Female clustering in cockroach aggregations – a case of social niche construction?

    Stanley, Christina; Preziosi, Richard F.; Liddiard Williams, H.; University of Chester, University of Manchester, Manchester Metropolitan University (Wiley, 2018)
    Individuals in groups can suffer costs through interactions with adversarial or unknown conspecifics. Social niche construction allows individuals to buffer such potential costs by only engaging in preferred associations. This may be particularly beneficial in insect aggregations, which are often large and highly fluid. However, little is known regarding the structuring of such aggregations. Here we use social network analyses to test for fine-scale social structure in resting aggregations of the sub-social cockroach Diploptera punctata and to explore the social pressures that contribute towards such structure. We showed that females were significantly more gregarious than males and formed the core of the proximity network, thus demonstrating a higher level of social integration. This fine-scale structure is likely to result from females displacing males; females initiated most displacements whilst males received the majority. We explain this behaviour in terms of social niche construction by showing that females received significantly fewer approaches and investigations at more female-biased local sex ratios. We therefore suggest that female social clustering occurs in this, and presumably other, species to reduce potential costs associated with male harassment. This demonstrates how social niche construction can lead to higher level social structure; we suggest this approach could be used across a range of species in order to improve our understanding of the evolution of sociality.
  • Extraction, identification and biological activities of saponins in sea cucumber Pearsonothuria graeffei

    Khattaba, Rafat A.; Elbandy, Mohamed; Lawrence, Andrew; Paget, Tim; Rae-Rho, Jung; Binnasera, Yaser S.; Alih, Imran; Taibah University; Suez Canal University; Jizan University; Alarish University; University of Chester; Sunderland University; Kunsan National University; Central University, New Delhi (Bentham Science, 2018-04-01)
    Secondary metabolism in marine organisms produced a diversity of biological important natural compounds which are unpresented in terrestrial species. Sea cucumbers belong to the invertebrate Echinodermata and are famous for their nutraceutical, medical and food values. They are known for possession triterpenoid glycosides (saponins) with various ecological roles. The current work aimed to separate, identify and test various biological activities (anti-bacterial, antifungal, antileishmanial and anticancer properties) of saponins produced by the holothurian Pearsonothuria graeffei from the Red Sea, Egypt.

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