Genes controlling eye development and light sensitivity differed between the Northern krill from the Atlantic Ocean versus the Mediterranean Sea, researchers found.
Photo: Andreas Wallberg / Uppsala University.
A groundbreaking study led by researchers from Uppsala University, Sweden, in collaboration with an international team, has revealed that Northern krill (Meganyctiphanes norvegica) exhibit remarkable genetic adaptations that enable them to cope with climate change.
The findings, published this month in Nature Communications, provide crucial insights into how key marine species can survive in rapidly changing environments, potentially offering strategies for protecting marine ecosystems in the future.
The research team, led by bioinformatician Per Unneberg and researcher Andreas Wallberg from Uppsala University, conducted a comprehensive study on Northern krill, small marine crustaceans that play a vital role in ocean ecosystems as a food source for whales, seals, and fish.
By sequencing and comparing the DNA of 74 krill specimens from various regions of the North Atlantic and Mediterranean, the researchers uncovered extensive genetic variation within the species.
"Understanding how genetic adaptation works in krill can help us better predict which populations are more or less resilient to climate change," said Unneberg in a press release. "Since so many species in the ocean depend on krill, this knowledge is an important element in protecting marine ecosystems when the climate changes."
The study identified hundreds of genes associated with adaptation to both hot and cold environments, including genes related to light and heat sensitivity, nutrient uptake, and reproduction. These genetic adaptations are crucial for the survival and reproduction of krill in diverse climates.
"The krill genome is six times larger than that of humans and contains unique copies of many genes," Unneberg explained. "Our research shows that specific gene copies may have played an important role in the krill’s ability to adapt to both cold and warm waters. Our results may be of great importance for the conservation of important genetic diversity and marine ecosystems."
The study suggests that certain populations of Northern krill, particularly those in Scandinavian fjords, may serve as genetic "hot spots" for future adaptation to a warmer North Atlantic and Arctic.
Conserving these populations could be crucial for maintaining genetic diversity and resilience in marine ecosystems, the researchers say.
"This research gives us a new insight into how plankton can survive in a world of rapidly changing climate by adapting genetically," said Wallberg.
"What we have learned about the Northern krill can also be used to understand how other species can cope with climate change – such as the Antarctic krill, which is an important but declining species in the Antarctic ecosystem."
The study emphasizes the importance of mapping and conserving genetic diversity in marine species to ensure the stability of marine ecosystems amid climate change.
The findings can also inform conservation strategies for other key marine species, helping scientists and policymakers develop effective measures to protect ocean biodiversity, the researchers said.
The full study, Unneberg, P. (et al. 2024). Ecological genomics in the Northern krill uncovers loci for local adaptation across ocean basins. Nature Communications, can be read here: https://doi.org/10.1038/s41467-024-50239-7
