Contact

Most birds do not have a penis, and most ornithologists have not thought about bird penises much. However, evolutionarily, the loss of the penis in birds is an extremely significant event: why lose an organ that seems so handy to get sperm close to female eggs? The few birds that have kept their penis may offer some insights as to why this penis loss may have occurred in birds. Waterfowl are remarkable in the variation of their genital morphology. In some waterfowl, males force copulations on females, and in these species males have longer and more elaborate penises, and females have convoluted vaginas that redirect paternity to her chosen mate. Male-male competition plays a critical role in influencing the morphology of the penis, surprisingly within the lifetime of an individual. The evolutionary history of avian genitalia is complex, and has had interesting consequences to avian behavior.

The first part of my talk will focus on the use of drones for the monitoring of wildlife. In this project, we evaluated the use of a drone equipped with a thermal infrared camera as a tool to monitor moose (Alces alces) in Scandinavia’s boreal forest. We first investigated the factors affecting moose detection probability and then estimated local moose population density. Additionally, we compared the efficiency of drone and ground approaches to detect and observe GPS-collared female moose and their calves and quantified how these approaches affected moose behavior and space use. The second part of my talk focusses on the interactions of moose and beavers, and how they are mediated by forestry. Specifically, we (1) analyzed GPS data to quantify habitat selection by moose in relation to riparian areas and Eurasian beaver (Castor fiber)  presence, (2) used camera traps to investigate if beaver lodges affect the diversity and relative abundance of other mammals, and (3) conducted shoreline transects to evaluate the role of moose density and forest structure on beaver occurrence and foraging patterns.

Climate change and biodiversity loss have led to an urgent need to maintain and restore genetic processes within and among plant populations in human-modified landscapes. Landscape genetics is a field which was born as an amalgation of landscape ecology and population genetics, and hence offers excellent tools for enhancing our knowledge of the role of land use change, climatic and topographic factors in shaping the genetic structure and gene flow of plants. Using plants in biodiverse semi-natural grasslands as an example, I will provide an overview about how our group has applied landscape genetic approach to track the gene flow of plants and touch upon some lessons we learned on this road. Finally, I will show how our landscape genetic studies led us to conduct a citizen science campaign in 30 European countries.

Mammalian teeth and mammalian gastrointestinal tracts are examples of convergent evolution to increase chewing efficacy and the use of microbes not only as service providers but as nutrients. The ruminant system combines several characteristics that make the combination of teeth and the digestive tract more than its components. This presentation is a travel through the ingestive and digestive adaptations of mammals.

Elucidating the mechanistic basis of adaptive variation in organismal performance is a central goal of evolutionary physiology. Aerobic performance, a complex trait, depends on the coordinated function of multiple physiological systems, with metabolic pathway flux and mitochondrial function playing critical roles. Investigating how evolved differences in organismal physiology shape aerobic capacity offers a powerful framework for understanding the evolution of complex traits. This is particularly relevant for animals facing oxygen limitation, whether from environmental hypoxia or from energetically demanding activities such as prolonged diving. In this talk I will present my research on how metabolic pathways are shaped by environmental challenges, with examples ranging from animals living in high-altitude hypoxia to ongoing work in diving birds.

 

Once largely confined to poultry, Highly Pathogenic Avian Influenza (HPAI) viruses, especially H5N1 strains, has shown increased spread among wild birds, with persistent circulation year-round, particularly in Europe, where seasonal patterns have shifted from winter outbreaks to sustained, multi-seasonal presence. This change in ecology contributes to broader geographic spread and higher transmission risks. HPAI has traditionally just affected bird populations, but recent developments show increased spillover into mammalian species, raising serious public health concerns. Notably, the virus is now infecting mammalian species, including wild carnivores and marine mammals, with growing reports of mortality and sporadic human infections. These cross-species events highlight the virus’s zoonotic potential and its pandemic risk if it acquires efficient human-to-human transmission capabilities. The talk underscores the urgent need for global surveillance, One Health collaboration, and preparedness strategies to address this evolving viral threat.

Biodiversity is the foundation of resilient ecosystem services that sustain human well-being. However, advancing impacts of intensive land use, climate change, and resource overexploitation critically threaten biodiversity - particularly in the tropics. This talk will highlight the far-reaching challenges arising from these developments as well as the opportunities tropical ecology provides for a sustainable future.

The focus will be on key findings from international research on the interactions between biodiversity and land use across tropical regions, including long-term studies in cacao agroforestry systems in Indonesia, Cameroon and Peru. Field experiments from Peru, for example, demonstrate that birds and bats can increase cacao yields by up to 118% through natural pest control, corresponding to nearly USD 959 per hectare each year. Similar results across continents show that tropical land-use systems can be managed both profitably and biodiversity-friendly, depending strongly on landscape context, shade levels, and the functional diversity of interacting species such as pollinators and predatory arthropods.

Translating this knowledge into practice requires diversity at multiple levels - through the inclusion of varied communities, methods, and perspectives that bridge knowledge and implementation gaps. Such diversity can advance global Sustainable Development Goals by linking environment, society, and economy. Tropical ecology thus points the way toward our shared sustainable future and illustrates how ecological knowledge can inform practical solutions for biodiversity conservation, sustainable agriculture, and human well-being.

Non-shivering thermogenesis (NST) is one of the most fascinating evolutionary achievements, enabling high body temperatures and successful radiation of mammals and birds into cold environments. In many mammals, the mechanism of adaptive NST relies on the mitochondrial heater protein, uncoupling protein 1 (UCP1), in brown adipose tissue (BAT). In humans, dissipating excessive nutrient energy via thermogenesis in adipose tissue represents an attractive route to reduce obesity and its comorbidities. To unravel specific pathways that could be instrumental in therapeutically targeting human adipose tissue, we use unique animal models to receive evolutionary clues how thermogenesis was wired into adipose tissue. My laboratory has transformed our view on BAT evolution using comparative approaches, highlighting that some thermogenic pathways emerged late during mammalian evolution. Using bioenergetic approaches, we demonstrate that the thermogenic function of UCP1 has only sparked in the stem placental ancestor.

The authors introduce an authority-building perspective on scholarship, examining how scholars' citation outcomes are related to two behaviors that scholars repeat over time: building universalist authority by publishing in top-tier journals, and building social authority by collaborating with peers who occupy central positions in the collaboration network of their discipline. Analyzing a unique longitudinal database of 134,558 business scholars from 1960 to 2020, the authors find that citations reward scholars for building social authority rather than for publishing in high-quality journals. However, the authors also demonstrate that building social authority can lead to “ghetto effects,” where research fields become isolated and less cited. Specifically, for research fields in which scholars maintain few collaborations with peers from other fields, building social authority leads to fewer citations for the collective production of that field. The authors conclude that journals and universities should guard research fields against the negative consequences of building social authority and offer recommendations on how to mitigate these consequences.

Human culture is remarkable in its complexity and cumulative nature, but the evolutionary roots of the mechanisms enabling it remain debated. One key factor may be the interaction between cognition and social tolerance. My research investigates fundamental processes for cultural evolution, namely how social tolerance shapes collective problem solving, innovation, and social learning. Using cooperatively breeding common marmosets (Callithrix jacchus), I showed that groups outperform individuals on problem-solving tasks, not simply by pooling abilities but because groups achieved solutions beyond what any single individual managed alone, indicating that their collective performance was greater than the sum of its parts. These findings highlight that collective problem solving emerges along a continuum shaped by social tolerance. I extended this line of work to other primates. In a comparative study of capuchin monkeys, I found that tufted capuchins (Sapajus apella), which display higher tolerance in co-feeding contexts, were more successful at solving novel foraging puzzles than less tolerant white-faced capuchins (Cebus capucinus). In ring-tailed lemurs (Lemur catta), I tested whether repeated social learning opportunities allowed for the gradual accumulation of task knowledge. Tolerant stable dyads performed best, while replacement dyads and solitary individuals showed poor performance, suggesting that low tolerance in some pairs disrupted information transfer and constrained collective intelligence. Together, these studies provide converging evidence that social tolerance is a critical moderator of problem solving and innovation in primates. They suggest that the human trajectory of cumulative culture may have been facilitated not only by cognitive capacity but also by cooperative social systems that enhanced tolerance, sustained collaboration, and allowed knowledge to be maintained and recombined across individuals.