2023-07-11 15:02:05
BELOVED BLACKSMITH
Pars
Updated Tuesday, July 11, 2023 – 15:02
The genetic patterns found could serve to identify other endangered insects, especially pollinators, and avoid a serious ecological problem.
Glaucopsyche alexis, closest European relative to Xerces Blue.ROGER VILA / CSICZoonomy Project The genome of 240 mammal species that will help fight diseases Environment The chimpanzee genome holds the key to combating its illegal trade
The wings of the Xerces Blue butterfly (Glaucopsyche xerces) were an intense iridescent blue color, in contrast to the characteristic white spots on its ventral area (abdomen). The last specimens of this species, endemic to the coastal dunes around the city of San Francisco (California), were found in 1941 and its disappearance made it a global icon of human-caused extinctions. This week a team led by researchers from the Institute of Evolutionary Biology (IBE-CSIC-UPF) and the Barcelona Museum of Natural Sciences details in the scientific journal eLife the sequencing of the genome of four specimens of this butterfly, a work that allows us to better understand the events that led to its extinction and that opens the door to the possible recovery of the species.
In addition to Xerces Blue, the authors have also sequenced the genomes of seven other specimens of Silvery Blue (Glaucopsyche lygdamus), its closest relative in evolutionary terms, which lived between 80 and 100 years ago, from the Smithsonian Institution in Washington. . So, the researchers have been able to recompose the evolutionary path of both species -which diverged between one and two million years ago- and confirm that they are two different evolutionary lineages.
Comparison of the genomes of both species has also revealed that the DNA of the Xerces blue butterfly contained a high incidence of inbreeding, a sign of population decline, a finding that could be used to identify other insect species threatened by human activity. The extinction patterns of these animals, contrary to what happens with vertebrates, are not well understood today, despite the fact that the disappearance of insects, especially pollinators, is a serious ecological problem.
“There are many endangered insects whose situation goes unnoticed because it is extremely difficult to census their populations, which in general seem very abundant to us”, explains Roger Vila, researcher at the IBE (CSIC-UPF) and lead author of the research. “However, they can be very sensitive to climate variations and human action, for example, to pesticides. That is why we believe that the genomic traits that indicate the reduction of the population of the Xerces blue butterfly can serve as an alert today and help detect vulnerable insects in future studies.”
Demographic decline
The results of the research indicate that the Xerces Blue butterfly experienced a large population decline over tens of thousands of years, probably caused by climate change (which did not affect Silvery Blue in the same way). The authors explain having detected the characteristics of a small population in the genome, traits that include low genetic diversity, long chromosomal fragments without genetic variation, and a high frequency of deleterious alleles (which impair the viability of individuals and turn the species into a species). vulnerable).
With this antecedents, the destruction of their habitat by humans was the trigger for their final extinction: the growth of the city of San Francisco eliminated much of its habitat and its population was relegated to the Golden Gate National Park where it continued to decrease until it disappeared. Iconic to Californian wildlife, the Xerces Blue butterfly became a symbol of insect extinction around the world.
Debate on ‘de-extinction’
On the other hand, the sequencing of its genome could pave the way towards de-extinction (techniques that make it possible to regenerate living specimens of an extinct species) of this butterfly. In recent years, the possibility of applying this process to bring extinct species back to life has aroused the interest of the scientific community, but it also raises questions. debates over its ethical and ecological implications.
“The issue of de-extinction is controversial, but at the same time it offers a message of hope,” says the other leader of the study, Carles Lalueza-Fox, a researcher at the IBE (CSIC-UPF) and director of the Museum of Natural Sciences in Barcelona. “It is proposed as a form of ecological restoration, and in this sense, Xerces blue would be a good candidate for various reasons: in the Presidio park, in San Francisco, the ecosystem of coastal dunes where it was endemic is being restored, and it could complete the restoration of this environment.In addition, being an organism with a limited dispersal and that appears a few weeks a year, It would not represent the danger of becoming a pest“, aade.
According to the criteria of The Trust Project
Know more
#genome #Xerces #Blue #butterfly #icon #humancaused #extinction #sequenced