Dr. Dustin R. Rubenstein Columbia University Causes and Consequences of Sociality: Spanning Molecules to Populations Dustin Rubenstein is a Professor of Ecology, Evolution and Environmental Biology at Columbia University in the City of New York. At Columbia, he is the Director of the Center for Integrative Animal Behavior and Chair of the University Seminar in the Integrative Study of Animal Behavior. He is also an Affiliate Member of Columbia’s Zuckerman Mind Brain Behavior Institute and Data Science Institute, as well as a Faculty Mentor in the Doctoral Program in Neurobiology and Behavior. As an innovative leader in undergraduate education, Rubenstein led the creation of the Program in Tropical Biology and Sustainability, a semester-long study abroad program in Africa, and the sTEAM Fellows Program, a team-based interdisciplinary summer research program for first year students from underrepresented groups. He is also the youngest faculty member to lecture in Frontiers of Science, part of Columbia College’s undergraduate Core Curriculum. Rubenstein received his A.B. from Dartmouth College in 1999 where he was a Reynolds Scholar following graduation, and his Ph.D. from Cornell University in 2006 as a Howard Hughes Medical Institute Predoctoral Fellow in the Biological Sciences. He was then awarded a Miller Research Fellowship to conduct postdoctoral work at the University of California, Berkeley from 2006-2009. He has held appointments at the American Museum of Natural History, the National Museums of Kenya, the Museum of Vertebrate Zoology at Berkeley, and the Cornell Lab of Ornithology. In recognition of his research accomplishments, Rubenstein has received young investigator awards from the Animal Behavior Society, the American Ornithologists’ Union, the Society for Behavioral Neuroendocrinology, and the University of Michigan. He is a Fellow of the American Ornithological Society and has been recognized by the National Academy of Sciences as both a Kavli Fellow for his research accomplishments and as an Education Fellow in the Sciences for his innovation in STEM teaching. Additionally, he has been acknowledged for his teaching, scholarship, and mentoring by Columbia University with a Lenfest Distinguished Faculty Award and by the Society of Columbia Graduates with a Great Teacher Award. His research takes an integrative approach to understand why complex animal societies form and how organisms cope with environmental change through studies that combine behavior, ecology, and evolution with those of the underlying molecular and neuroendocrine mechanisms. He has studied a variety of animals, including reptiles, mammals, birds, crustaceans, and insects in Central and South America, Africa, Asia, and Australia. Rubenstein is the author of over 125 publications and the market-leading textbook Animal Behavior, as well as co-editor of the book Comparative Social Evolution.
Signal evolution and species coexistence: visual signals as mediators of interspecific interactions Species coexistence is a key step in diversification, so learning about the traits that allow closely related species to live together is a central goal in understanding the origin and maintenance of biodiversity. Signals, specifically, can allow individuals to avoid costly interactions, but we still have much to learn about between-species signaling. My work focuses on signal evolution in birds, asking which signals play important roles in encounters with members of other species, and how these signals reduce unfavourable aggressive and mating interactions. Here, I use citizen scientist-captured photographs and videos to characterize the visual signals that birds use in aggressive interactions with other species, a comparative analysis to ask whether colour pattern broadcasts interspecific dominance status, and field experiments to test the contributions of competing alternative hypotheses in driving colour pattern divergence among co-occurring species. Together, this work paints a new picture of the key role that visual signals play in mediating interspecific interactions among coexisting species, and shows how similar selective pressures may drive both within and between-species signal evolution.
Dr. Lauren Erland University of British Columbia Phytohormones as mediators of plant climate change resilience Chemistry, University of British Columbia, Okanagan Campus, Syilx Okanagan Nation Territory
Climate change threatens an estimated 20 % of the world’s plant diversity. Canada, and particularly Canada’s arctic and alpine environments, are experiencing these changes at more than four times the global rate. Plant adaptations to climate change require endogenous systems to perceive environmental changes and respond by redirecting growth, detoxifying stress metabolites and stabilizing physiological processes. The indoleamines melatonin and serotonin are an unusual class of plant growth regulator which are known for having dual function: stress defense and morphogenesis. My research has shown that melatonin, serotonin and their metabolites have distinct responses and effects in response to environmental or developmental cues, that presence of novel conjugate or storage forms of melatonin and serotonin may have biological relevance, and that localization of melatonin and serotonin are important in determining their biological activity, particularly in response to thermal stress. This led to my current research interests in arctic and alpine plant species as changing temperatures are a hallmark of climate changes. While some species are highly adapted to specific environments, including extremes of temperature, others are capable of survival in these extremes and in more moderate climates. These generalist species from arctic and alpine environments are interesting models which I am studying to understand the role of phytohormone networks in determining plant climate change resilience. This research has implications for both understanding plant environmental stress responses, as well as, identifying novel roles of the indoleamines melatonin and serotonin in these processes. About Lauren Erland : Lauren Erland is a Postdoctoral Fellow in Dr. Susan Murch’s PlantSMART Lab at UBC Okanagan. She holds a BSc in Microbiology and an MSc in Biochemistry and Molecular Biology from UBC. Lauren completed her PhD in Dr. Praveen Saxena’s lab at the University of Guelph, where she focused on understanding the roles of the mammalian neurotransmitters melatonin and serotonin in plants. Her research uses interdisciplinary approaches such as plant tissue culture, metabolomics, analytical chemistry, ecological niche modelling, and quantum dot microscopy to study the role of plant growth regulators in plant perception and response to changes in their environment. Her current role is as part of a collaborative project which aims to bring Syilx traditional ecological knowledge together with Western Science to address community led questions. She is particularly interested in how plant signaling can be applied to understand and predict climate change resiliency of Native Canadian plant species in the Okanagan Valley and Canada’s Arctic (Inuit Nunangat). Dr. Katie Marshall University of British Columbia Causes and consequences of low temperature limits in invertebrates While biogeographical theory has frequently suggested that poleward range limits are set by abiotic factors such as temperature, it remains unclear what role low temperature tolerance plays in setting these limits. In particular, species distribution modelling methods that rely on correlative approaches may underestimate the role that plasticity plays in setting poleward range limits. My laboratory focuses on the physiology of low temperature tolerance in invertebrates, using several systems to test the causes and plasticity of limits to freeze tolerance and freeze avoidance. While these "bottom up" approaches are particularly powerful in well-characterized systems like spruce budworm where resources like genomes and population distributions are available, we also believe that invertebrate macroecology needs new and better tools for understanding the ranges and population sizes of invertebrates. So we have also been focusing on developing machine learning and metabarcoding methods to start developing datasets that can be used to test mechanistic hypotheses about the drivers of poleward range limits.
Ryan Kiburn pHD candidate, Plaxton & Snedden Lab Investigations into the multifaceted functions of Ricinus communis calcium-dependent protein kinase-1 (RcCDPK1) As the global population grows and demands on agricultural land rise, there is a need to increase crop yields. Castor (Ricinus communis) oil seeds (COS) have become an important model for oil seed metabolic engineering due to their massive accumulation of oil at maturity relative to commercially important oil seeds such as canola. In developing COS, a unique ‘bacterial-type’ phosphoenolpyruvate carboxylase (PEPC) isozyme is highly expressed as a regulatory and catalytic subunit of a novel Class-2 PEPC complex. Class-2 PEPC’s unique kinetic and regulatory properties, and dynamic subcellular targeting to the mitochondrial surface, support the hypothesis that it facilitates rapid refixation of respiratory CO2 while sustaining a large anaplerotic flux to replenish TCA cycle C-skeletons withdrawn in support of storage oil and protein biosynthesis in developing COS. R. communis Ca2+-dependent protein kinase-1 (RcCDPK1) catalyzes in vivo inhibitory phosphorylation of bacterial-type PEPC (BTPC) at Ser451 in developing COS (Ying et al. 2017 Plant Physiol.). This research aims to address how autophosphorylation influences RcCDPK1’s ability to transphosphorylate BTPC at Ser451. Interestingly, RcCPDK1 exhibits high sequence identity (83%) to its closest ortholog from the model plant Arabidopsis thaliana, AtCPK4, which also catalyzes Ca2+-dependent phosphorylation of COS BTPC at Ser451 in vitro. AtCPK4 also appears to regulate signal transduction of the stress hormone abscisic acid (ABA) by phosphorylating an important ABA-responsive transcription factor (AtABF4), raising questions about further overlap between substrates of these two CDPK orthologs, and ultimately whether RcCDPK1 might also function in castor ABA signaling. Using a mix of biochemistry and genetic approaches with a focus on enzyme kinetics and functional genomics, this project has uncovered novel aspects of RcCDPK1 regulation that shed light on autophosphorylation in CDPKs, as well as providing initial links between the control of central carbon metabolism and ABA signaling.
Patterns of species association: Quantifying and detecting patterns of association in ecological communities Patterns of non-random species association (co-occurrence), which are common, are frequently used as an indicator of the processes responsible for shaping ecological communities. While a great deal of effort has gone into developing and evaluating the statistical methods used to detect non-random patterns of association, and the metrics used to quantify them, questions remain about their performance. I present research investigating the performance of various methods and metrics used to explore species co-occurrence patterns and, ultimately, provide recommendations on what methods work for detecting significant patterns of association within ecological communities.
A new Genotyping-in-thousands by sequencing (GT-seq) panel for Canadian polar bears: population structure and sex-biased dispersal applications In the context of a rapidly warming arctic, effective management planning for polar bear (Ursus maritimus) subpopulations is limited by infrequent surveys and data deficits that preclude robust estimates of population trends. Genetic monitoring using non-invasively collected scat samples is an alternative that can mitigate some of the challenges associated with traditional monitoring (e.g. expensive, invasiveness) and provide opportunities for collaboration between Northern communities and Western scientists. Scat samples can provide numerous insights into individual- and population-level health, such as information on contaminants levels and diet. However, understanding this information relies on being able to reliably genetically identify individuals. To identify individual polar bears from non-invasive scat samples, we have developed and validated a new genomics method called Genotyping-in-Thousands by sequencing (GT-seq). We demonstrate that our new method can successfully genotype (>50% loci present) 62.9% and provide genetic identity for 80% of non-invasively collected fecal samples determined to contain polar bear DNA (i.e. from cells shed from the gut lining). Using an optimized, cost-efficient GT-seq panel of 324 Single Nucleotide Polymorphisms (SNPs), we are also able to comprehensively characterize polar bear population structure at similar levels to past studies that have used more invasive methods. Major contributors to contemporary population structure include dispersal (including sex-biased) and gene flow, yet few studies have been able to characterize sex-biased dispersal in Ursids. In my second data chapter, we aim to confirm sex-biased dispersal in polar bears using our new GT-seq assay and investigate density-dependent impacts on sex-biased dispersal through comparison of sex-biased dispersal patterns in subpopulations varying in bear density. This GT-seq test and the information it enables will provide the foundation of a non-invasive toolkit for polar bear monitoring and contribute to community-led programs - data from which can inform co-existence with polar bears, conservation, and policy decisions.
Dr. Tom Sherratt Carleton University Not all who wander are lost: exploration-exploitation dilemmas, and how animals resolve them There is frequently a trade-off between gaining new information (exploration) and using current information (exploitation). In some instances, this trade-off is mundane: should we play it safe and buy a familiar brand of wine we know is good (exploit), or take a risk and try a new brand that might be even better (explore)? In other instances, the trade-off is a matter of life and death: at what point in a clinical trial should researchers exploit their available information and switch all patients to an experimental drug if it looks like it works? Likewise, non-human animals regularly face exploration-exploitation dilemmas that have fitness consequences: should they attack an unfamiliar type of prey in the hope that it is edible (explore), or trust their instincts and leave it alone (exploit)? Should they continue to graze in the current field, or move elsewhere where the grass may be greener?
In this talk, I highlight the ubiquity of exploration-exploitation dilemmas and introduce the analytical and numerical techniques to solve them. Once the solutions are described, I show how many widely observed phenomena, from age-dependent neophobia in great tits to polymorphisms in butterflies, can be understood as a consequence of animals seeking to resolve this trade-off. The solution techniques to exploration-exploitation models are computationally demanding, and animals cannot possibly solve them by “doing the math”. Indeed, I describe experimental evidence showing how simple “rules of thumb” are able to predict the behaviour of decision-makers far better than the exact solution. Finally, I show how two separate Bayesian approaches to decision making in behavioral ecology, namely signal detection models (which predict strategic behaviour assuming complete information) and exploration-exploitation models (which predict strategic behaviour as information is gained), are deeply connected, with the former a special case of the latter. |
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