Jon E. Brommer

Short CV

2016-2019      Tenure-track professor 2nd stage (Associate professor), U of Turku
2012-2016      Tenure-track professor 1st stage (Assistant professor), U of Turku
2003               Docent in Evolutionary Biology, University of Helsinki
2001               Ph.D., University of Helsinki, Finland
1997               M.Sc, University of Amsterdam, The Netherlands
I currently am supervisor for 5 Ph.D. students within VERG (primary supervisor for Barbara Class, Jenni Poutanen and Pauliina Järvinen; secondary supervisor for Fabio Balotari Chiebao, Tytti Turkia). In the past, six students have been awarded their Ph.D under my supervision – Edward Kluen (2012), Jaana Kekkonen (2011), Pekka Kontiainen (2010), Natalia Pitala (2007), Patrik Karell (2007) and Kalev Rattiste, 2006).
Before I obtained my current position, my salary and my research has been mostly funded by the Academy of Finland (post-doc 2003-2004, 2005-2006; Academy Researcher 2006-2012). In addition, I received funding for a Ph.D. student project from the Academy of Finland (2003-2006) and the Nessling Foundation (2004-2007). My current project funded by the Academy of Finland "Evolutionary quantitative genetic of personality in the wild" focuses on applying evolutionary approaches on behaviors measured in wild birds and includes collaboration with Kees van Oers at the Netherlands Institute for Ecological Research (Wageningen, NL).
I have acted as opponent in several Ph.D. defenses and regularly act as expert for evaluation of grant proposals, docentships and Ph.D. theses. I regularly review papers for the major journals in ecology and evolution. During 2014-2016, I acted as reviewer and as chair (in 2016) of the scientific panel for Ecology, Evolution and Systematics of the Swedish Research Council (VR). At the moment, I have no editorial duties, but I have been editor-in-chief for Ornis Fennica and I was a review editor for Journal of Evolutionary Biology. I was head of the local organisation for the Nordic Society Oikos Conference in 2016, and am in the committee for the European Ornithological Union (EOU) conference in 2017, as well as European Society for Evolutionary Biology (ESEB) in 2019. All conferences held in Turku.
My publications can be found following links to personal pages given on the right-hand side of this page.
I try to keep a repository on GitHub with some useful computer code, the link to this repository can also be found on the right-hand side of this page. 

Research interests

My main interest lies in understanding broadly relevant ecological issues in wild populations: Why we see variation in morphology, behavior and life-history (i.e. reproduction and survival) and how such variation affects changes in abundance in wild populations. I typically work from an individual-based perspective. By marking individuals (e.g. a ring on the leg of a bird) and monitor the individuals in a population for a long time, you get information on which individual is related to which individual (a pedigree), and how well individuals survive and produce offspring (which defines selection, but also population growth rate). Most of my research is based on this kind of long-term, individual-based data exploring evolutionary and population dynamics. This work is of general relevance for gaining a better understanding of evolution and ecology, which can be applied to questions regarding conservation and management of wildlife. I also work on larger-scale studies based on coarse population-level monitoring such as working on factors underlying distributional changes and spatial variation in population sex ratios or abundances. Lastly, I do some work on issues in population genetics, mostly related to wildlife conservation and management focusing on the genetic consequence of bottlenecked populations.

 Study systems

Blue tit

Since 2003, I have been working in a nest-box breeding population of blue tits, conveniently breeding around my house (of course, I placed the boxes there). My original interest was to conduct a long-term, individual-based study including an experimental design aimed to improve estimation of quantitative genetic parameters. To this end, essentially all broods in the population were reciprocally cross-fostered in 2005 – 2010. Since then, the focus has been on continuing the protocol without cross-fostering. Although the “Basic Ecological Protocol” (measure all you can) is followed, focus in the last 10 years has been especially on behaviors. A protocol for several “easy-to-measure” behaviors has been developed. Such behaviors include intensity of nest defense at different stages of the breeding cycle, aggression and breath rate when handling individuals, but also measures of individuals in an artificial environment (bird cage). The main drive is to integrate the quantification of behaviors into this long-term study. Many long-term studies measure morphology and life-history traits, but few also take behaviors on board despite the fact that anybody who has been handling individual animals immediately recognizes that individuals behave differently. As the data collected in this project keeps on building up, it becomes possible to answer increasingly more complex questions related to the general question of how variation in consistent behavior (animal personality) is maintained in a wild population.


Tawny owl

In the early 2000s, I started to collaborate with Kimpari Bird Project (KBP) ringers Kari Ahola and Teuvo Karstinen, who have been working on tawny owls since the late 1970s. My interest then was whether the different color morphs in this species differ also in terms of their life history. We quickly learned that they did. Brown tawny owls have lower survival compared to grey ones in this population. In addition, the plumage colouration is highly heritable, consistent with a one locus, two allele model with pigmented (brown) being dominant over unpigmented (grey). Further work, which then also involved my post-doc at the time, Patrik Karell, showed that the lower survival of the brown morph is driven by harsh (cold, snow-rich) winters. In fact, as the winters have gotten milder, survival of especially the brown morph has increased and also their frequency in the study population and in the national population has increased; a pattern we believe signals a microevolutionary change in response to climate change. Further work has identified that many other traits covary with coloration, strengthening the notion that the colouration in tawny owls is part of syndrome of many covarying traits which tend to be favored under different environmental conditions. At this moment, Patrik Karell and I are still working with the tawnies, and still trying to better understand how such highly heritable polymorphism under strong survival selection can be maintained in a population.

White-tailed deer

Finland has an introduced population of white-tailed deer, a North American species. Nowadays, these deer thrive and are an important game species. In the 1930s, however, only three female and one male arrived to Finland after a long journey and founded this population. My original interest, together with Jaana Kekkonen, was to investigate the genetic consequences of this extreme founder event. Despite clear reduction in allelic richnes, the Finish white-tailed deer harbour high heterozygosity and suffer only mildly from inbreeding depression. At the moment, my interest, together with PhD student Jenni Poutanen and collaborators from the Finnish Wildlife Institute (Mikael Wikström) and Luke Natural Resource Institute Finland (Jyrki Pusenius), is to use genetic tools and other non-invasive approaches to develop ways to estimate density of this game species. Our main drive is to explore whether density estimates can be obtained using Spatial Capture Recapture (SCR) approaches and - if so - what kind of setup is required.

Contact information

Section of Ecoloy
Department of Biology
University Hill
FI-20014 University of Turku
For E-mail click on link below (or type address in browser)

 Jon Brommer


 VERG links