Host: Prof. Dr. Michaela Hau

Effects of prenatal and postnatal environments on nestling and adult energy expenditure

Talk Gary Burness, Seewiesen
Within a population there exists variation among individuals in physiological traits. There is increasing recognition that the rearing environment, including that experienced prenatally, can affect the adult phenotype and contribute to this variation. Using captive Japanese quail, we have been exploring the role that temperature, experienced either pre- or post-natally, has on an individual’s growth rates and thermal physiology. To our surprise, we have found that effects can be long lasting, and influence adult energy expenditure. Using wild birds we have been testing whether maternally-derived antibodies, transferred to offspring via egg yolk, influence nestling metabolic rate and capacity to mount an immune response. Effects are detectable at the fledgling stage, although we cannot track effects in adults. These experimental systems highlight the role that early environmental effects have on an individual’s energy expenditure however direct links with fitness remain to be shown. [more]

Coping with change: The evolutionary ecology of stress

Talk Maren Vitousek
Why are some individuals, and some species, better able to cope with stress than others? When faced with an acute challenge – the attack of a predator, a severe storm, a major injury – hormones mediate changes in an enormous diversity of behavioral and physiological traits. Variation in these key mechanisms of phenotype can influence the ability to survive and reproduce. In this talk I will discuss how integrative research in free-living birds is providing fundamental insight into the capacity of individuals, populations, and species to persist in changing environments, and how selection shapes endocrine mediators of phenotype. [more]

A journey inside the nuptial gift of a spider

Nuptial gifts, consisting of male donations of nutritious substances to females, are widespread and diverse. They are used by males to attract females, secure sperm transfer and as parental investment. In a series of experimental laboratory studies I have explored the evolutionary significance of gift giving in the spider Pisaura mirabilis, addressing both, male and female reproductive interests. Males exploit female foraging motivation by offering an insect prey wrapped in silk, that is eaten by the female during mating. The gift increases both, male mating success and fertilization success by prolonging sperm transfer. Interestingly, males also produce worthless (non-nutritive) gifts consisting of prey leftovers rather than genuine prey gifts. These males successfully ‘cheat’ females into mating while minimizing the costs associated with gift production (i.e. a missed meal), but suffer from shortened copulations. Results from my on-going research address the potential ecological drivers for worthless gifts in a natural spider population, such as intra-sexual competition and prey availability, and unearth how nuptial gifts may become a target of sexually antagonistic co-evolution, where cheating via worthless gifts leads to female resistance to the trait. [more]

Early life effects on later life performance: mechanisms and time scales

Talk Pat Monaghan, Seewiesen
Conditions experienced early in life can have profound effects on phenotypes and subsequent life histories, and these effects can operate over different time scales and across generations in some cases. During early life, the environment can induce phenotypic effects which, while they may have short term benefits, can also carry long term costs. In this talk I will particularly concentrate on how variation in the plane of nutrition and in the level of stress exposure in early life can have long term consequences for fitness related parameters. This is based on experiments that we have carried out mainly in birds and fish, involving both field and laboratory based studies. I will also discuss a number of mechanisms that can underpin these effects, including changes to the reactivity to external stressors and to telomere dynamics, and discuss to what extent these induced changes might be adaptive. I will also briefly discuss the implications for conservation biology of these long lasting environmental effects on phenotypes. [more]

Alex Jordan, Max Planck Institute for Ornithology and University of Konstanz: Mechanisms of social influence in animal groups

Talk Alex Jordan, Seewiesen
Understanding how individuals in social groups and collectives interact and influence each others’ behaviour is a central challenge in modern science, and an analysis of how the nature, frequency, and fine-scale detail of these interactions leads to emergent properties at the level of the collective is essential for achieving progress in fields ranging from the dynamics of information exchange in digital systems, human societies, and social organisms. In this talk I will discuss ongoing research using computational ethological techniques, analyses of neuroanatomy and neural activity, and traditional ecological field observations to understand the evolution of social behaviour. In my lab we leverage the incredible diversity of social behaviours and social systems present in the Lamprologine cichlid fishes of Lake Tanganyika to uncover the mechanisms and evolutionary pathways to complex social behaviour and group structure. [more]

Karen Spencer, University of St. Andrews: Developmental programming in birds: integrating data on in ovo and external stimuli

Talk Karen Spencer, Seewiesen
Even before it is born the conditions an animal experiences can have profound long-term effects on its health and wellbeing. In birds, mothers deposit a range of nutritional and hormonal factors into the egg that can alter embryonic development. If the mother experiences stress during egg laying a higher level of stress hormones are deposited into the egg, which can alter the development of the neuroendocrine system then controls the ability to respond to stress. In later life adults exposed to pre-natal stress have been shown to exhibit altered stress responses, fear-related behaviours and there is very good evidence that they are more likely to develop negative health issues. Work carried out by myself and colleagues suggests that in ovo conditions can program later behaviours via neuroendocrine systems and that these conditions may act as a signal to the offspring to alter development in such a way as to maximise survival in the post-natal environment, but that that there will also be costs associated with this strategy. However, oviparous species are often also exposed to many external factors as well, without the buffer of the maternal body as in mammals. The fact that birds use acoustic calls to communicate in many different contexts, such as calling to chicks or alarm calls when stressed, suggests that these calls can provide salient cues as to the quality of the environment. However, whether they provide such cues to embryos is unknown. We still have much to learn about the importance of different types of acoustic stimuli in shaping later phenotypes. Here I will detail some of the new experiments going on in my lab to investigate the adaptive significance of pre-natal acoustic stimuli. I will suggest that we should consider both in ovo and external stimuli as programming factors and work is now needed to integrate the two stimuli types to determine if re-programming of embryonic phenotypes is possible when environmental conditions change over the incubation period. [more]

Will Cresswell, University of St. Andrews: Connectivity in migrant birds and its implications for their population dynamics and conservation in a changing world

Talk Will Cresswell, Seewiesen
Any underlying theory to explain why migrants are more prone to population declines than non-migratory species must arise from the differences between these two groups in their ability to deal with accelerated rates of habitat and climate change in the Anthropocene. Recent theoretical advances have therefore concentrated on understanding how migrant and resident birds differ in their evolutionary response to climate and habitat change, in particular how migrants are likely to be under selection to be bet-hedging generalists which makes them well adapted to climate change and habitat shifts but relatively poorly adapted to habitat loss and any site-based conservation solutions to address this. The main differences between migrants and residents are:1. Migrants generally have a bet-hedging strategy with high migratory spread (low connectivity) over a large non-breeding area, and greater natal and breeding dispersal than residents. 2. Migrants depend more on a chain of suitable sites that must be correctly arranged in space and time for a successful annual cycle to be completed.I will discuss how these characteristics lead to population dynamics and so potential conservation solutions for migratory birds, as many populations continue to decline. [more]

Kate Buchanan, Deakin University: Effects of early life on vocal communication

Talk Kate Buchanan, Seewiesen
In wild animals - and also for humans, the start you receive in life has profound and long lasting impacts on your behaviour, physiology and fitness. I am fascinated by how early life experiences impact on avian cognition and development, particularly focusing on the trait of vocal communication. The development of the songbird brain and consequent song production is known to exhibit considerable plasticity in relation to environmental conditions. Whilst stimulation enables neural development and complex cognitive abilities to develop, environmental challenges cause stunting during periods of neural growth and reduce the capacity of animals to perform complex cognitive tasks. My work focuses particularly on the impact of developmental stress on neural control mechanisms and song output in a number of songbird species. Our recent work show that the mechanism not only involves volumetric changes in the embryonic brain, but also the capacity of this brain to learn new vocal signatures. We know that early developmental stress affects song within generations and my current work is testing the potential for such effects to be mediated across generations, both through environmental stress and parental communication. In recent years we have become interested in prenatal communication, the impact on the developing brain and its relevance for long term developmental programing in birds. Here, I will present the current research from my group addressing the effects of early life experience on neural development, behaviour and physiology in zebra finches. [more]

Timothy J. Greives, North Dakota State University: Mechanisms and importance of timing in a constantly changing world

Talk Timothy J. Greives
Nearly all animals live in environments that experience dramatic fluctuations in environmental variables across daily and annual times scales. Daily and seasonal rhythms are hypothesized to enable animals to anticipate these environmental changes and appropriately adjust physiology and behavior in advance of these environmental shifts to enhance survival and reproductive success. In the wild, relationships between environmental variables of interest (e.g. daylength or sunrise) and individual variation in expression of behaviors or traits that influence fitness are often observed, yet the underlying mechanisms responsible for integrating multiple cues and regulating timing decisions are often unclear. In contrast, decades of laboratory investigations have generated a wealth of knowledge of underlying physiological mechanisms shaping these rhythms, however the relationships between these mechanisms and their contribution to evolutionary fitness in the highly variable environment of the wild remains unclear; only in the wild can fitness-related traits be quantified in a meaningful way. My research programs seeks to integrate studies grounded in behavioral ecology and physiology to begin to uncover the key sources of variation that influence timing decisions and their fitness implications in the wild. Specifically, my research asks: What are the mechanisms that influence initiation of daily behaviors and initiation of seasonal activation of reproductive physiology and behavior? How does individual variation in these daily and seasonal timing responses in physiology and behavior influence fitness? And, what are the evolutionary pressures, or costs, that have shaped the physiological processes regulating these timing decisions? Here I will present representative studies that highlight the integration of behavioral ecology and physiology in songbirds and outline future lines of research that I will pursue that will begin to address these key questions. [more]

Michael Romero, Tufts University: Stress Physiology in Conservation: Predicting Human Impacts on Wildlife

Talk Michael Romero, Seewiesen
Species populations can decline for many reasons, but stress on individuals of those populations can make all of those reasons worse. Our recent and ongoing work has focused on two related questions: can chronic stress of individuals be used as a proxy for the health of the population; and how exactly might a stress response put a population at greater risk of decline? The ultimate goal is to use measurements of the stress response as a tool in vertebrate conservation. [more]

CANCELLED --- Simon Verhulst, University of Groningen: Corticosterone, Telomeres and Life Histories --- CANCELLED

Talk Simon Verhulst, Seewiesen
Telomere length is a predictor of life span in humans and other species, raising the question how variation in telomere length arises. Because telomere length declines with age, telomere length at any time point is the outcome of telomere length at birth and subsequent telomere dynamics. I will discuss recent findings on both factors, with special attention to the role of corticosterone. [more]

Vincent Careau, University of Ottawa: Energetics, behaviour and performance: trait (co)variance across genotypes and species.

Talk Vincent Careau, Seewiesen
During this presentation, I will outline the research program I have put in place over the past five years at the University of Ottawa, on the coadaptations between metabolic, performance, and personality traits. I will present the first results obtained from studies on wild mice, laboratory insects, as well as humans. A common theme in all of our research is the use of quantitative genetic techniques to partition the (co)variance between several traits at different levels of variation. Doing so commonly reveals trait associations that are otherwise undetectable at the aggregated level. [more]

Susan Alberts, Duke University: "The medicine of life": Social life and survival in primates

Talk Susan Alberts, Seewiesen
Longitudinal studies of animal social behavior and demography allow us to understand how environments at one stage of life affect fitness outcomes at another stage of life. This question is important both in the biological sciences and in the human social sciences. Here, I briefly review evidence from the human social sciences that document, and raise important questions about, the profound links between early life, adult life, and longevity. Next, I draw parallels between those studies and biological studies of wild animal systems, where researchers have long studied these links. I argue that wild animal systems, by answering questions that are difficult or impossible to answer in human studies, shed light on the deep evolutionary roots of the human sensitivity to the social environment. They also provide insight into the mechanisms by which environments at one stage of life affect survival outcomes at a later stage of life. Most of the examples I discuss come from my long-term research project, the Amboseli Baboon Research Project. [more]
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