5/6 #BOU2023 #SESH4
Our results are surprising, as they are partially in contrast to the expectation from genetic rescue literature. Next steps will be investigating mating choices among these different groups and introgression of immigrant genes on longer time frames.

4/6 #BOU2023 #SESH4
We found striking differences in multiple fitness components between the different groups, whereby F1s experienced heterosis (fitness increase), and F2s experienced epistatic breakdown (fitness loss), which was also reflected in overall fitness.

3/6 #BOU2023 #SESH4
We then tested these predictions using detailed life history data to model zygote and sex specific juvenile survival, and adult lifetime reproductive success in a Bayesian framework. Then we combined these estimates into an overall fitness approximation.

2/6 #BOU2023 #SESH4
Based on 40 years of data from a population of song sparrows (Melospiza melodia) we created groups of individuals with specific fitness expectations from line cross theory, including heterosis and epistatic breakdown following outcrossing.

1/6 #BOU2023 #SESH4
What are the genetic and fitness consequences of natural immigration in a wild meta-population?

I am a PhD candidate in evolutionary biology at CBD at NTNU @ntnu supervised by Jane Reid, Henrik Jensen, Lukas Keller, Peter Arcese and Pirmin Nietlisbach.

6/6 #BOU2023 #SESH4
This work was carried out at CBD at NTNU @ntnutogether with my supervisors and Debora Goedert, funded by NSERC / CRSNG and Norges forskningsråd. We are thankful to the Tsawout and Tseycum First Nations for allowing continuing access to X̱OX̱ DEȽ (Mandarte Island).

1/6 #BOU2023 #SESH4 : Seasonal migration is a critical movement allowing individuals to escape from seasonal extremes. To predict how populations might respond to increased seasonal variation it is crucial that we understand the development of traits like movement and survival.

5/ #BOU2024 #Sesh4 For other city traits, only birds with high urban tolerance respond strongly, with occurrence increasing with city wealth and decreasing with city size greenness but only for these species.

4/ #BOU2024 #Sesh4 Our results show that for some traits of cities, species respond the same way regardless of their urban tolerance, with species occurrence declining with increased city size and night time light.

3/ #BOU2024 #Sesh4 We collected urban occurrence data from scientists and birdwatchers in Ontario’s cities asking them assess breeding occurrence of birds in their cities. We used this data to calculate a mean occurrence score for each species weighted by the observer’s ability.

3/ Six years of artificial selection (grey shading) succeeded in switching that spatial difference: a quantitative genetic model showed that birds in the East had genes for laying larger clutches than birds in the West onlinelibrary.wiley.com/doi/abs/10.111… #BOU2023 #SESH4

1/7 #BOU2024 #SESH4 . FID (Flight Initiation distance: Distance at which animals flee from an approaching threat) is a behaviour used to understand how animals adapt to the urban life. FID is shorter in cities than in non-urban areas

I'm excited to be at BOU Urban Birds conference #BOU2024 and to be presenting some of my recent work with Glasgow Urban Ecology Group in #SESH4 . I'll be chatting about what is driving differences in Blue Tit reproductive parameters and population growth. Come and say hi 👋 #ornithology

4/ When selection ended, this difference disappeared almost as quickly as it had been created (figure shows the genetic change between 1981 and 2021, as predicted by 1000 samples of our model)... #BOU2023 #SESH4

2/ Erik Postma and I are studying the great tit population on the Dutch island of Vlieland to understand how adaptation, drift and gene flow shape evolution. On Vlieland, great tits in the West lay bigger clutches (more eggs) than those in the East #BOU2023 #SESH4

5/6 #BOU2024 #SESH4

🐣 Considering the extremes of our gradient, we see reduced productivity in the urban site.

🐦Overwinter survival in adult Blue Tits is higher in our urban site compared to the non-urban site, which may help compensate for reduced productivity.

5/ …yet natural selection on clutch size was relatively weak. So if not driven by in situ adaptation, is gene flow the main driver of evolution at local scales? #BOU2023 #SESH4

6/6 #BOU2024 #SESH4

Increased availability of Oak and Birch leads to earlier egg laying, more fledglings and caterpillars. This highlights the importance of completing food chains in urban areas.

Higher adult survival in urban Blue Tits may compensate for reduced productivity.

4/6#BOUsci23 #SESH4
Next, it’s the flowchart for trajectory reconstruction process.

1/6 #BOU2024 #SESH4 #ornithology

Urbanisation is occurring rapidly across the globe. Urban areas are characterised by:

🌆 Increased amounts of impervious surfaces;
🌆 Altered microclimates;
🌆 Novel community compositions