Scientists have mapped out over 50,000 snail species on Earth. Of these, about 500 different species live in the ocean or on the shore from subtropical to Arctic waters.
- There are very few species in the ecosystem that are as diverse and adaptable as snails, says Anja Marie Westram. She is an evolutionary biologist and researcher at Nord University and the Institute of Science and Technology (IST) in Vienna.
Westram is the project manager for a group of marine biologists and genetic researchers from universities in the United Kingdom, Spain, Sweden and Norway, that is doing research on snails (gastropods).
- Bold and pionering marine research
Marine snail field. Researcher Anna Marie Westram is the project manager for The genomic basis of temperature adaptation across space. The FRIPRO project has received 11.2 million Norwegian kroner from the Research Council of Norway. Photo: Joost Andre M Raeymaekers
The FRIPRO project named The genomic basis of temperature adaptation across space has received 11 million Norwegian kroner from the Research Council of Norway (RCN).
In this project, the researchers will map out and study the populations of marine beach snails, from warm seawater in Spain and Italy, to colder waters along the coasts of Great Britain, Iceland and Norway and to the Arctic part of Russia.
- The climate is getting warmer and beach snails can give us knowledge about how changes in temperature affect genes of species, Westram says.
The specie rough Periwinkle snail (Littorina saxatilis) is an expert in local adaptation according to the researchers.
How do marine snails adapt to changes in temperature?
The researchers study the beach snails living on rocks, in the salt water and on the beach rocks in different temperatures, and the snail genes must be analyzed using powerful computers, so-called gene sequencing.
- Our goal is to understand and explain how populations of snails genetically adapt to the change in temperature in the tidal zone. By doing this we will be able to contribute to the understanding of how species' genes adapt to climate change, as documented by the UN's Intergovernmental Panel on Climate Change (IPCC), Westram says.
The common beach snails live in the tidal zone, where there are extreme fluctuations in temperatures and in the supply of oxygen. Littorina saxatilis has developed a lung-like structure in addition to gills in order to survive in this extreme environment.
Snails that live in higher or lower parts of the tidal zone have different physiological adaptations.
On the Swedish west coast. The tidal zone is diverse, and the shore snail is a popular marine snail species for evolutionary geneticists. This picture is from Bohuslän on the west coast of Sweden. Photo: Roger Butlin
The shore snails that live in the higher part of the beach rocks have adapted to higher oxygen levels than the snails at the waters's edge.
- There is still a lot we do not know about genetic adaptation, despite a lot of new research in this field. In this research we will thoroughly analyse the genomic data about how this marine snail adapts to temperature, because today's models do not consider all of the large and important ecosystems, such as the bustling life between high and low tide, Westram says.
The snail populations in the tidal zone live close to each other
The shore snails live in small communities, usually only a few meters apart, but they are still different in both appearance and size. According to the researchers, the genus probably contains large amount of genetic variation.
- Because of this large genetic variation and the differences in adaptation on small geographical scales, L. saxatilis is also a good system to study how populations become more and more different and maybe eventually evolve into completely different species.
- We know that local adaptation involves genetic adaptation to local conditions, but we do not know much about how new barriers for reproduction limit the flow of genes in and between the shore snail populations. The point is that the process changes the genetic landscape and thus also the diversity of species.
Marine thermometers? A group of rough Periwinkle snails (Littorina saxatilis) near, Bodø in Norway. Photo: Joost Andre M Raeymaekers
(Article translated from Norwegian by Helen Hillevi Ruud, Nord University)