Reducing the Ecological Impact of Field Research

Researchers and students at biological field stations, especially in remote areas, are subject to leaving “footprints,” as we conduct research, work, and live in sensitive ecosystems. These footprints include travel, personal trash and waste, and field equipment (e.g. flagging, tree markers, plot markers, trail markers, monitoring devices, etc.). In this commentary, we argue that the field of primatology's commitment to minimum impact research should be more explicitly and visibly integrated into our ethical protocols with regard to field research and instruction in sensitive environments. We review current ethical codes and potential solutions to reducing our “researcher footprints” while conducting fieldwork. Using Costa Rica as an example, we address how sustainable fieldwork differs among varying cultural contexts and argue that researchers should be made responsible and accountable for how our presence, research, and teaching might impact the environment. We conclude by recommending a set of guidelines to be added to ethical protocols regarding research design, station policies, and the conduct of research and teaching in the field. Am. J. Primatol. 75:1‐9, 2013. © 2012 Wiley Periodicals, Inc.     

Hormonal Correlates of Paternal Care Differences in the Hylobatidae

Only one of the 15 species of monogamous hylobatids, the siamang (Symphalangus syndactylus), demonstrates direct paternal care in the form of infant‐carrying, providing a unique model for examining hormonal correlates of paternal care differences between siamangs and gibbons. We used behavioral data and fecal hormone analysis to investigate (1) differences in monthly percent father–infant proximity in relation to monthly fecal androgen metabolite concentrations from infant birth to the late postpartum period between siamangs and gibbons, (2) the pattern of change in fecal androgen and fecal estrogen metabolite concentrations during the 8‐week peripartum period between siamangs and gibbons, and (3) the change in mean fecal glucocorticoid metabolite concentrations at 1‐month postpartum from individual baseline between siamangs and gibbons. Father–infant proximity increased as androgen concentrations decreased over the postpartum period in siamangs but not in gibbons. Androgen concentrations increased around birth in siamangs during the 8‐week peripartum period, but exhibited a decreasing trend around birth in gibbons. Estrogen concentrations increased from pre‐ to postpartum in siamangs during the 8‐week peripartum period, but exhibited a decreasing trend from pre‐ to postpartum in gibbons. The difference in mean glucocorticoid metabolite concentrations from baseline was greater in siamangs than gibbons. Our data suggest a relationship between specific steroid hormone patterns and differences in paternal care among the hylobatids, warranting further investigation of such proximate mechanisms.     

Functional innovation through vestigialization in a modular marine invertebrate

Few studies show how morphological vestigialization may facilitate functional innovation. Fewer still describe the co‐occurrence of the derived and more ancestral structures in the same genetic individual. In the present study, we explore that rare instance in a modular (colonial) marine invertebrate. Using laser scanning confocal microscopy with fluorescent staining and behavioural observations, we describe homologous structures in polymorphic modules (zooids) in the bryozoan Bugula flabellata and document the occurrence of previously unreported retractor and circular muscles in the more derived module, the bird's‐head avicularium. In the evolution of a sessile feeding zooid to a moveable nonfeeding zooid with sensory and grasping functions, transformations were effected in the food‐capture apparatus, orificial structures, musculature, and sensory structures. We expand on and clarify previous reports of homologies between ancestral and derived modules in bryozoans and argue that vestigialization and augmentation of homologous structures were coincident with functional innovations in the avicularium. The present study offers rare evidence for the evolution of functional innovation through vestigialization. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 104 , 63–74.     

Ca2+ and UVB Radiation Have No Effect on E-Cadherin-Mediated Melanocyte-Keratinocyte Adhesion

Direct cell-cell contact between melanocytes and keratinocytes has been shown to play an important role in the regulation of human melanocyte function and skin pigmentation. An important role for the calcium-dependent epithelium-specific cell adhesion molecule, E-cadherin, in melanocyte-keratinocyte adhesion was suggested previously. To further clarify regulation of E-cadherin-mediated melanocyte-keratinocyte interactions, we investigated the effects of physiological (Ca²⁺) and environmental (ultraviolet B [UVB] radiation) stimuli on the expression and functional activity of E-cadherin in melanocyte-keratinocyte adhesion. Expression of E-cadherin mRNA was detected by Northern blot analysis in cultured normal human melanocytes at levels similar to those in keratinocytes. Flow cytometry analysis with anti-human and anti-mouse-E-cadherin antibodies (anti-uvomorulin and ECCD-2) showed that cultured normal human keratinocytes, melanocytes, and two metastatic melanoma cell lines express E-cadherin strongly on the cell surfaces. Melanocyte adhesion, particularly to differentiating keratinocytes (cultured in 1.2 mM calcium) but not to proliferating keratinocytes or to fibroblasts, was decreased by 41.7 ± 4.5% in the absence of 1 mM Ca²⁺ during the binding assay. Addition of anti-mouse-E-cadherin antibody (ECCD-1) to the binding assay inhibited the adhesion of melanocytes to differentiating keratinocytes by 88.2 ± 1.1%, while addition of anti-P-cadherin antibody (PCD-1) had no effect. The levels of E-cadherin expression in melanocytes were not changed by the presence of calcium (1 mM) in the medium or by UVB irradiation (20 mJ/cm²) for one day before flow cytometry analysis. Moreover, these treatments had no effect on melanocyte-keratinocyte adhesion. These results demonstrate that E-cadherin is strongly involved in melanocyte adhesion to keratinocytes and suggest the implication of E-cadherin in the overall regulation of the skin pigmentary system.