Erica Leder sitter på en båtbrygga vid Tjärnölaboratoriet
Photo: Susanne Liljenström

Evolutionary biologist Erica Leder: I always wanted to work at a place by the sea


Erica Leder's research is about what happens deep inside the smallest building blocks of life. About how genes and environment together create an individual with all its characteristics. After a research career that took her around the world, she has settled on the Swedish west coast and the Department of Marine Sciences.

Erica Leder is Senior Lecturer at the Department of Marine Sciences.
Erica Leder is Senior Lecturer at the Department of Marine Sciences.
Photo: Susanne Liljenström

Erica Leder is a researcher with an unusually wide repertoire: The adaptability to new environments in gobid fish, the large sex differences in colors and behavior in sticklebacks, evolution of shell types in Littorina snails, and sperm evolution in passerine birds.

But, behind the seemingly widely different research areas is actually one and the same question: How populations and species can develop and adapt to their surrounding environment through natural and sexual selection. Erica Leder approaches this question on a very basic level – what is going on in the DNA and the genes:

"Every organism is an interesting case study. It´s all about dissecting the phenotype."

Genes and environment makes the individual

The term "phenotype" refers to the appearance of an organism and all its physical characteristics and traits. Things we can see and measure; such as body size, eye color, blood type. From an evolutionary perspective, selection operates upon the phenotype. The phenotype results from an individuals´ DNA code, or its genotype, and the influence of the environment that controls which genes are actually expressed.

"Much of the phenotype is encoded in the DNA, or specific beneficial traits would not be able to evolve. It is trying to make the connection between genotype and phenotype that I find interesting. How do the genes interact and how are they regulated to then, after many steps, produce a phenotype", says Erica Leder.

The interest in genetics built up slowly. Ericas undergraduate was in resource and recreation management, her master was on the ecology of Dungeness crabs. But a course in fish biology opened her eyes for the variation in forms and behavior of various fish species.

Erica Leder looking for Littorina snails among the rocks.
Erica Leder spends a lot of time in front of the computer, but the work also includes some field studies. Here, looking for Littorina snails on the rocky shore right outside of Tjärnö Laboratory.
Photo: Susanne Liljenström

Doctoral thesis on Arctic charrs

Erica Leder did her PhD on two closely related species of Arctic charrs in Alaska; one living in lakes and one living in the ocean. Somewhere during the process, she realized that the phenotypic appearance of something does not always tell the whole story.

"I was trying to understand how you decide what is a species and what is not a species. And then I got more and more into the function of genes: If something looks different – what are the genes that are responsible for this differences that you see?"

Starting as an environmental biologist and ecologist, Erica Leder describes herself as a molecular geneticist as well as a genome biologist/bioinformatician.

"Most of my research now is a little bit of field work, a little bit of lab work and lots of bioinformatic work analyzing gene sequences and gene expression."

The mechanisms behind biodiversity

The research Erica Leder is doing is usually referred to as basic science. Basic science is sometimes difficult to justify since there is not an immediate societal outcome. However, in order to make informed decisions about managing and preserving biodiversity we need to understand how diversity is generated or maintained through genomic processes, Erica Leder points out. It is important to understand what is the mechanism that shapes the diversity that we observe in nature:

"What genomic variation do you have that allows populations to handle variation in the environment? What is the buffering capacity in the genomes? In some cases you need to understand that at the genomic level, what the genes do and how they interact."

Erica Leder is involved in several projects with collaborators around the world. For example, the genetics of the invasive round goby, the mechanisms of parallel evolution in Littorina snails, population genetics of the Western Australian Seahorse, and passerine bird genomics related to sperm evolution.

Erica Leder and a bullfinch male.
Erica Leder does not only study marine species in her research. Among other things, she investigates the evolution of sperm in bullfinches.

The research on birds she does together with her Norwegian husband who is an evolutionary biologist at the Natural History Museum in Oslo. They first met in the US during Erica’s PhD and then again when she was doing field work in Norway.

"We started collaborating on some bird research projects, and after almost ten years things just clicked.. We still have joint projects, including studying bullfinches around our cabin in the Norwegian mountains. Both my husband and I are very committed to our research - when other couples might go to the cinema in their free time, we talk science!"

Tjärnö provides many opportunities

Erica Leder started her position at the Department of Marine Sciences, with Tjärnö Marine Laboratory as work place, at in the summer of 2020. She then came from Nofima, a Norwegian institute focusing on aquaculture. . Before that she has lived and worked in six different countries, including several universities in the United States, but also in Canada, Finland and in Estonia.

"It is quite common in the US, jumping from university to university. I wanted to learn certain techniques with certain research groups, and at the time that it seemed a good idea to follow that."

Through membership and field grants from the Centre for Marine Evolutionary Biology, CeMEB, Erica Leder had visited Tjärnö several times. She always enjoyed the friendly atmosphere and the beautiful surroundings.

"I feel there are so many opportunities at Tjärnö Marine Laboratory with permanent and visiting scientists, master students, undergraduate students and PhD-students, and all the outreach activities. I always wanted to work at a place by the sea, working with marine organisms".

So maybe this is the final job destination?

"It may sound silly, but it is my dream job!"

Text: Susanne Liljenström

Facts Erica Leder

Academic title: Senior lecturer

Working place: Tjärnö Marine Laboratory, Strömstad

Born in Virginia, US, in 1967

Interests: Cycling (road and trails), cross-country skiing, snowboarding with my sister and her kids.

Dream project:  Being able to understand the diversity of sperm phenotypes across various species. Sperm are the most diverse cell type in the animal kingdom, yet they all have the same function – so, why are they so different?