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Erika Fernlund IsakssonPhD student

About me

I am a PhD student in sexual selection working under the supervision of Dr. John Fitzpatrick. In this doctoral thesis, I am working with the pygmy halfbeak (Dermogenys colletti), a species showing a wide range of sexually selected traits including weaponry and ornamentation as well as associated behaviours of courtship and contest competition (pre-mating selection). Since female halfbeaks engage in multiple mating, there is also sexual selection after mating in the form of sperm competition and crypic female choice. Plus, males invest in large testes relative to their body size, up to 8-10%! 

Male (under) courting a female halfbeak. Credits: Hannah Ogden.

These guys are native to Southeast Asia, which is why I went to Singapore and Malaysia in 2019 with post-doc Alessandro Devigili. Out of this trip came an interesting study on wild halfbeaks, published in Frontiers Ecology and Evolution. Link below. Other than that, I have been working on assessing the resource-dependency of sexual trait investment, in male and female halfbeaks, both during pre- and post-copulatory selection. 




Devigili A, Fernlund Isaksson E, Puniamoorthy N and Fitzpatrick JL (2021) Behavioral Variation in the Pygmy Halfbeak Dermogenys collettei: Comparing Shoals With Contrasting Ecologies. Front. Ecol. Evol. 9:607600. doi: 10.3389/fevo.2021.607600