PhD Projects 2011

Fitness consequences of social foraging

Abstract We want to establish Molossus molossus as a model system where we can quantify the fitness consequences of social foraging in a free-ranging mammal. This species is energetically limited due to it's morphology and foraging mode as well as the short availability window and patchy distribution of their food (insect swarms). One adaptation to deal with this problem and probably at least a major reason for living in closed societies in this species is increased foraging efficiency through group hunting. With a combination of state-of-the-art methods (transponder based surveillance of the population, automated telemetry, playback experiments, genetic approaches) we want to assess the costs and benefits of this behavior in a population in Panama. This project is a collaboration with Arne Ludwig from the Institute for Zoo and Wildlife Research in Berlin and Kamran Safi from the MPIO Radolfzell.

Keywords information transfer, evolution of sociality, fitness, group size, ecological niche

Main advisor Dina Dechmann, MPIO Radolfzell

Molecular genetics of animal behavior in wild bird populations

Abstract Correlated natural variation in sets of behavioral traits have been observed in bird populations. This project is aimed to measure such variation by field experiments and to analyse the underlying mechanisms and consequences on the molecular genetics level.

Keywords behavioral genetics, personality, fitness consequences, candidate genes, selection signatures

Main advisor Jakob Müller, MPIO Seewiesen

Molecular and cellular mechanisms of fin regeneration in zebrafish

Abstract In contrast to mammals, fish retain the remarkable ability to regenerate a variety of tissues. The differences in regeneration ability might be due to different protein activities and/or regulative processes of the involved molecules. The zebrafish caudal fin is a particularly attractive model of regeneration because the fin is a relatively simple structure, quick to regenerate, and nonessential to the viability of fishes. Regenerating fins form a blastema by dedifferentiation of existing cells, which then proliferate and finally differentiate again to replace the damaged tissue types. Zebrafish are also amenable to molecular and genetic manipulations, including transgenic techniques and forward genetic screens. We could recently show that the retinoic acid signaling pathway is essential for the formation of the blastema. The project is to investigate the contribution of microRNAs and epigenetic changes in the process and to develop techniques to visualize and to genetically manipulate the regeneration process. The project will utilise zebrafish using a variety of approaches including immunofluorescence, microinjections, and the development of transgenics.

Prior experience in cell biology or developmental genetics, preferably in vertebrates, is essential. You should be familiar with molecular genetic techniques, e.g. PCR, sequencing, and cloning. This project is being conducted within the laboratory of Prof. Axel Meyer, which combines both world-class fish breeding and molecular laboratory facilities.

Keywords zebrafish, regeneration, retinoic acid, miRNA, epigenetic mechanisms

Main advisor Gerrit Begemann, University of Konstanz

Gestural signalling in bonobo (Pan paniscus) infants in the wild

Abstract Language has often been used to define what it means to ‘be human’. Children begin to display nascent forms of communicative skills such as pre-linguistic gestures at around their first birthday. But how do these gestures differ between humans and other animals?

By combining the ethological approach with methods of Comparative Psychology, our group investigates this question by focusing on the development and cognitive complexity underlying gestural behavior in different human cultures, closely related species and species living in comparable social systems.

The PhD-project will especially focus on the gestural behavior of bonobo infants in the wild (Lui Kotal, DRC). This project is a collaboration with Gottfried Hohman and Barbara Fruth from the Max Planck Institute for Evolutionary Anthropology in Leipzig.

You should have a background in Biology/Psychology or a related field. Previous experience with fieldwork, especially in tropical rain forests is essential, experience with great apes or monkeys is preferred. You should be physically fit, highly motivated, independent, responsible, and fluent in French.

Keywords language, gestures, cognitive complexity, development, Pan paniscus

Main advisor Simone Pika, MPIO Seewiesen

Gestural signalling in chimpanzee (Pan troglodytes) infants in the wild

Abstract Language has often been used to define what it means to ‘be human’. Children begin to display nascent forms of communicative skills such as pre-linguistic gestures at around their first birthday. But how do these gestures differ between humans and other animals?

By combining the ethological approach with methods of Comparative Psychology, our group investigates this question by focusing on the development and cognitive complexity underlying gestural behavior in different human cultures, closely related species and species living in comparable social systems.

The PhD-project will especially focus on the gestural behavior of chimpanzee infants living in two different chimpanzee communities (Ngogo, Kanyawara, Uganda) in the wild. This project is a collaboration with John Mitani, University of Michigan, USA, Martin Muller, University of New Mexico, USA and Richard Wrangham, University of Harvard, USA.

You should have a background in Biology/Psychology or a related field. Previous experience with fieldwork, especially in tropical rain forests is essential, experience with great apes or monkeys is preferred. You should be physically fit, highly motivated, independent, responsible, and fluent in English.

Keywords language, gestures, cognitive complexity, development, Pan troglodytes

Main advisor Simone Pika, MPIO Seewiesen

Evolutionary physiology of birds

Abstract Our main research interest is to understand the ways in which animals evolve physiological adaptations to the environment in which they live. We focus on the evolution of three physiological systems: i) seasonal reproduction, ii) endocrine control of behavior, and iii) circadian rhythms. Currently we investigate, for example, how individual variation in physiological organization translate into various components of fitness. Our main study species is the great tit, Parus major, a well-studied and abundant species across Europe. We approach microevolutionary questions using natural variation in the wild, phenotypic engineering (hormone manipulations), telemetry, and behavioral observations, eventually extending into quantitative genetics approaches.

Keyword evolution, physiology, hormone, stress, behavior, fitness

Main advisor Michaela Hau, MPIO Radolfzell

Speciation and genomics of cichlid fishes

Main advisor Axel Meyer, University of Konstanz

The involvement of the ubiquitin-like protein FAT10 in pathogen defence

Abstract The ubiquitin-like protein FAT10 is strongly inducible by pro-inflammatory cytokines in most tissues and is covalently conjugated to a large variety of substrate proteins (Aichem et al. (2010) Nature Communications 1, doi:10.1038/ncomms1012; Groettrup et al. (2008) Trends Biochem. Sci. 33: 230-237). FAT10 is the only ubiquitin-like protein which directly targets substrate proteins for degradation by the proteasome. Recently, we have identified a viral protein which is conjugated to FAT10. This finding gave rise to the hypothesis that FAT10 may be involved in the defence against intracellular pathogens by targeting viral proteins for degradation.

In this project we want to challenge FAT10 deficient mice with a number of bacterial and viral pathogens in order to determine if their immune response to these pathogens is defective. If for certain pathogens an attenuated pathogen clearance and immune response can be found, the functional involvement of FAT10 will be investigated.

Keywords Cytotoxic T lymphocytes, immune response, pathogen defence, proteasome, degradation, virus, bacteria, infection

Main advisor Marcus Groettrup, University of Konstanz

Memory traces in the brain

Abstract Little is known about the physiological mechanisms which enable animals to associate temporally disjunct stimuli. Two simple behavioral paradigms to study the association of temporally disjunct stimuli are trace conditioning and backward conditioning. In trace conditioning a meaningful unconditioned stimulus (e.g. electric shock) is presented after the conditioned stimulus (e.g. odor) has terminated. In backward conditioning the sequence is reversed: here the odor follows the electric shock and the animal learns to associate the absence of an electric shock with the odor.

We use the model Drosophila melanogaster to study the physiological basis of trace conditioning and backward conditioning. In particular, we aim to investigate neural representations of stimulus traces and neural mechanisms that underlie associative learning in trace and backward conditioning. The work comprises optical imaging, genetic manipulation, behavioral experiments and computational approaches.

Keywords learning and memory, olfaction, neuronal mechanisms, Drosophila, optical imaging

Main advisor Paul Szyszka, University of Konstanz

The song learning related genome of birds

Abstract Learned vocalisations are the exception in animals and occur in birds only in songbirds, parrots, and some hummingbirds. Songbirds have to learn their songs from conspecific tutors. To do so, songbirds evolved a specific neuronal circuit for song production and learning. This system of well defined brain nuclei is unknown in taxonomic sister-groups and the underlying developmental mechanisms for the differentiation are not understood so far.

In a genetic screen using songbird microarrays developed in our group as well as next generation sequencing, we are planning to identify genes, which define the development and function of the song system.

In relation, we want to analyse the transcriptome of the song system from a selected group of songbirds species and compare it to the transcriptome of homologous brain regions in non-songbirds from South America.

We are looking for a PhD candidate who would like to pursue a thesis which involves molecular biological work with microarrays and modern sequencing techniques, as well as bioinformatics, to mine the aquired data for candidate genes and to perform in silico pathway analysis.

Main advisor Manfred Gahr, MPIO Seewiesen

Electrophysiological study of vocalizations of crows

Abstract Songbirds use a specialized neural circuit for singing of learned sounds, the song system. The neural mechanisms of song production and learning are a model for human speech learning. In order to study neurophysiological correlates of singing, we invented a radio-transmitter that allows the monitoring of the brain activity in freely behaving small animals. Here we intend to adapt this technique to crows, a songbird species, for two reasons: 1. crows have large song systems that allow the simultaneous recordings of two song control regions and 2. crows have a large repertoire of individual learned communication calls. Thus, the aim is to study the dynamics of neural activity during vocal communication in a natural setting of crows.

Main advisor Manfred Gahr, MPIO Seewiesen

Movement ecology of African flying foxes

Abstract Eidolon helvum is a species that plays an important role for humans and ecosystems in Africa as it is on the one hand a long-distance seed disperser and important source for bush meat, on the other hand it may also be a reservoir for human relevant diseases. Also interesting about this species is that it spends at least half of each year on a long distance migration, during which most of the reprodcutive cycle takes place. In a collaboration with the Ghanian Wildlife Services, veterinaries from the University of Cambridge and the Zoological Society of London we are conducting a GPS-tracking as well as a genetic study to determine the migration route and follow social groups during their yearly cycle. We are also looking at the physiological consequences of hunting pressure and living in the city.

Keywords Small and large scale movement ecology, ecosystem services, hunting pressure and physiological consequences

Main advisor Dina Dechmann, MPIO Radolfzell

How is learning and memory of the honey bee affected by environmental factors?

Abstract Honey bees (Apis mellifera) are among the most important "farm animals" because they play an important role in the pollination of various crops. However, honey bees are threatened by various environmental factors: several diseases (e.g. colony collapse disorder, foulbrood), parasites (e.g. the Varroa mite) and the use of pesticides has caused massive losses of honey bees during the last years. This project will investigate the effects of these environmental aspects on learning and memory, based on the observation that learning and memory play an important role in honey bee behavior and thus might be used as an early alarm signal to estimate the honey bees' state of health. We will develop a novel learning paradigm and measure the influence of diseases and pesticides on honey bee learning and memory. Neurophysiological measurements, such as in vivo brain imaging, will be used to unveil the underlying mechanisms. The project combines behavioral analyses, computational developments, calcium imaging and brain physiology. The successful candidate should have a strong background in neuroscience and in computational analyses.

Keywords honey bees, learning, memory, stress, behavior

Main advisor Giovanni Galizia, University of Konstanz