We have updated our privacy policy to explain how we use your non-public data.
We use cookies to provide you with a better experience. You can read our cookie policy here.
Commercial whaling in the 20th century decimated giant whale populations, but it also appears to have had a lasting effect on the genetic diversity of today’s surviving whales, according to a new study from Oregon State University.
The researchers compared DNA from a collection of whale bones discovered on beaches near deserted whaling stations on South Georgia Island in the South Atlantic Ocean with DNA from whales from the existing population and uncovered strong evidence of the loss of maternal DNA lineages in blue and humpback whales. . .
“A maternal lineage is related to an animal’s cultural memories, such as feeding and breeding sites, that are passed down from one generation to the next,” said the study’s lead author, Angela Sremba, who conducted the studies as part of her doctoral studies in Oregon. . University Marine Mammal Institute Estatal. Si you lose a maternal line, chances are you lose that wisdom as well. »
The effects recently appeared in the Journal of Heredity.
South Georgia is a remote island located about 800 miles southeast of the Falkland Islands and is home to several whaling stations that operated from the turn of the century until the 1960s. In just over 60 years, more than 2 million whales have been killed in the South. hemisphere, totaling 175,000 near South Georgia.
Evidence of this slaughter is still found on the island, which is replete with thousands of whale bones, many of which are a hundred years old or older, that were discarded for processing. The cold temperatures of the region have contributed to its preservation.
Subscribe to the daily Technology Networks newsletter and receive the latest science news straight to your inbox every day.
“For 60 years, whales have been absent from South Georgia’s feeding grounds, suggesting that cultural reminiscence has been lost,” said Baker, Ph. D. holder. advise. ” The number of whales returning to this domain is not yet large, but there is a sense that they could rediscover this habitat. “
To better understand the conceivable impact of whaling on the genetic diversity of the existing population, Sremba analyzed DNA extracted from bones discovered on the island of South Georgia and compared the genetic data with previously published data on live whales from the fresh post-hunt population.
She and her colleagues learned about humpback, blue and fin whale bones and found that while genetic diversity among whales remains high, there are indications of a loss of maternal DNA lineages in blue and humpback whale populations.
The researchers were unable to find differences in diversity between DNA samples from Southern Hemisphere fin whales before and after hunting, likely due to the limited availability of post-hunt samples.
Since some whale species can live up to 100 years, it’s also conceivable that some of today’s whales were alive during the whaling era, said Sremba, who is now a researcher at OSU’s Hatfield Marine Cooperative Institute for Marine Resources and Ecosystem Studies. Newport Science Center.
As those whales die, this can lead to additional loss of additional maternal lines. This underscores the importance of preserving the whales’ genetic data now, he said.
“It’s remarkable that those species have survived. A hundred years from now, we don’t know what might replace them, and we can’t measure any substitution today if we don’t have an intelligent perception of the past,” Sremba said. “These paintings give an opportunity to piece together the history of those whale populations and help us understand what was lost due to whaling activities. “
Rising temperatures due to climate change could also lead to DNA deterioration in bones from South Georgia Island, Baker said.
“These paintings are a way to maintain this story indefinitely,” he said.
Reference: Sremba AL, Martin AR, Wilson P et al. Mitochondrial DNA diversity in 3 species of giant whales before and after whaling. J Heredity. 2023: esad048. is what I: 10. 1093/jhered/esad048
This article has been republished from the following documents. Note: Possibly the draping would have been modified in terms of duration and content. For more information, please tap on the source cited.