Chilean limpets: evolution and genetic diversity on our coasts

Paulina Quiroz Mella, Journalist UACh.- Understanding how oceanographic factors shape marine biodiversity was the main objective of the research entitled “Comparative genetics of barnacle populations in a biogeographic transition zone reveals common patterns of genetic structure and demographic history”lead by Livia Fluffystudent of Doctorate in Sciences, mention Ecology and Evolution from the Faculty of Sciences of the Austral University of Chile (UACh).

The study, published in the scientific journal “Molecular Ecology”, focused on comparatively evaluating the population genetics and historical demography of four species of limpets of the genus scurria: scurria scurra, Scurria variabilis, caecilian scurria and Scurria araucana. As explained in the text, the distribution of genetic diversity is closely associated with current transitions, but also with environmental changes that affected our coastline in the past.

In this context, the study was able to associate certain elements of topography and oceanographic processes that shape seascapes to the current distribution of genetic diversity in this species. Currently, in Chile comparative studies of population genetics are scarce, making it difficult to understand how evolutionary processes shape the diversity of organisms that exist today on our coasts.

genetics and geography

State-of-the-art sequencing and bioinformatics technology was used to assess patterns of genetic differentiation, allowing researchers to look at tens of thousands of genes at once. Likewise, several statistical correlation analyzes were carried out to describe the spatial configuration of genetic diversity and infer the role of the environment in this distribution.

The results obtained indicated that there are areas on the coast where there are “jumps” or breaks in the distribution of the genes of these species. These “jumps” indicate that something in the environment prevents the limpet larvae from passing from one side of these territorial breaks to the other. Added to this is the fact that these are sites common to several species, which corroborates that the environmental differences that exist between these regions affect the way in which many species are distributed.

“Shared genetic jumps can be linked to historical climate stability and oceanographic features that act as soft barriers to dispersal, evidencing the need to compare multiple species and those inhabiting the same geographic area to understand the influence of a particular seascape on diversity. genetics”, indicated Lívia Peluso.

In the same way, he added that, although it was not the objective of this study, differences were also found in the distribution of some of the species with respect to what had been previously reported in the literature, which reveals an important phenotypic variability in the shells between species.

“Also, the results yielded a clear and previously unknown latitudinal segregation, where S. variabilis was only observed at sites north of 34° S. (Christmas, O’Higgins Region); S. araucana was found only north of 36° S (Concepción, Biobío Region.); while S. ceciliana was only located in sites south of 36° S”added the researcher.

The academics Bernardo Broitman; Marco Lardies; Roberto F. Nespolo; and Pablo Saenz-Agudelo, the latter director of the Master of Science, mention in Geneticsfrom the Faculty of Sciences UACh.

As pointed out by the academic, it is essential to remember what the biologist Jacques Cousteau said, “you can’t protect what you don’t know”, this to emphasize that basic studies are very important.

“All ecosystems are extremely complex and understanding the evolution of the species that make them up is part of understanding how they work. Imagine what it would be like to try to repair an airplane if the engineers in charge did not know the function and position of each of the pieces that make it up; most likely that plane would not work well. The same thing happens in ecosystems, but with a much higher level of complexity. Only by deciphering their basic functioning can we understand them, and only by understanding them can we conserve and manage them effectively.”noted Dr. Pablo Saenz-Agudelo.

Finally, it is worth mentioning that the full article is available directly on the website of the scientific journal “Molecular Ecology”: https://onlinelibrary.wiley.com/doi/10.1111/mec.16978