Research on the adaptation of cod to environmental stress

Dr Till Harter joined the GEOMAR Helmholtz Centre for Ocean Research Kiel in mid-December to establish a new Emmy Noether research group. Previously, he was a postdoctoral researcher at McMaster University in Hamilton, Canada, where he studied the function of red blood cells and the physiological relationships between cardiovascular and respiratory function in vertebrates. “Many people have the simplistic idea that red blood cells are just a bag full of haemoglobin that carry oxygen. This is accurate to some extent for humans and mammals, as red blood cells lose their nucleus and cell organelles during the maturation process. However, red blood cells of most other vertebrates, including fish, have a nucleus. They can continue to produce new proteins and thus can respond to changing conditions - something we still know very little about,” explains Till Harter.

Focus on red blood cells from cod

The aim of the research group is therefore to find out how the red blood cells of fish change as a result of climate change and rising temperatures. In particular, cod (Gadus morhua) are being investigated - initially in the Baltic Sea and later also in the Atlantic along the Norwegian coast as far as Svalbard and in the Arctic. The aim is to analyse whether the red blood cells change in a way that is beneficial to the fish and enables them to adapt to the new conditions. Among other things, the performance of the fish will be analysed. In the course of the project, comparisons can also be made between the different regions.

“We are particularly interested in cod, because it is an important fish for fisheries, plays an important cultural role and is also very high up the food chain from an ecological perspective. If the cod is pushed out of some regions because it gets too hot, this could affect the entire food chain. The focus on cod also has a very practical reason: it is large enough to be able to take blood from it,” says Till Harter.

Limits to adaptability already known

Previous research has shown that there are limits to adaptability. For example, cod populations off the coast of France have been pushed northwards and no longer live as far south as they did a few years ago. Till Harter's research group is interested in these limits on a physiological level. “I'm interested in why these limits exist and why some cod populations can survive heatwaves of 20 degrees, but will perish at higher temperatures,” says Till Harter, “the aim here is to study the cellular mechanisms in red blood cells in detail”.

Background Emmy Noether Programme

With the Emmy Noether Programme, the German Research Foundation (DFG) supports outstandingly qualified postdocs and junior professors in an early phase of their scientific career. It enables them to qualify for a university professorship by independently leading an Emmy Noether Group over a period of six years.

Further Emmy Noether Groups at GEOMAR

Dr Nadine Mengis: ‘FOOTPRINTS’ on the topic of climate stabilisation (FB2)