PopCOmics comes to an end

 By Xavier Turon and Marta Pascual

Dear friends and followers of the PopCOmics project, we announce that the project ended officially the 30th September 2021. We have waited to make this post so that some papers with results could appear and a new project is up and running.

We are delighted with the outcome of PopCOmics, in which we have published ca. 40 WoS-listed papers with the results obtained, plus a long series of papers indirectly related with the project. This is much more than could be expected from the modest amount of funding that we had available, and is the result of the hard work of all team members.

We are also proud to have completed 3 PhD during the duration of the project, while another three are currently ongoing. This is complemented by a number of Master Theses and Bachelor Theses that showcase the formative achievements of PopCOmics.

We have also a strong output in the form of meeting presentations, divulgation activities and media appearances. The team has been keen in reaching both the specialized audiences and the general public.

We want to congratulate the team of the project for the important results obtained. It was fun and enjoyable working together in PopCOmics, and the general assemblies were memorable occasions.

We are happy to announce also that the next project has been funded by the Spanish Ministry of Science and Innovation, and started on September 2021. This new project, “Marine genomic challenges: from genes to communities” aka MARGECH project, will allow us to continue the development and application of molecular tools to pressing issues in marine ecology and biology. We will keep in mind, as always, the conservation focus and the need to respond to societal needs for high quality data and informed advice. Please bookmark the webpage of Margech https://margech.wixsite.com/margechproject and stay tuned for interesting news!

The MARGECH official logo

New PopCOmics paper

 

By Xavier Turon

The two sides of the Mediterranean: population genomics of the black sea urchin Arbacia lixula (Linnaeus, 1758) in a warming sea.

By Carreras, Ordóñez, García-Cisneros, Wangensteen, Palacín, Pascual, Turon

We are happy to have finally published our work on the population genomics of one of the focal species of PopCOmics, the black sea urchin Arbacia lixula. The new open access paper in Frontiers in Marine Science can be found at:

https://www.frontiersin.org/articles/10.3389/fmars.2021.739008/full

This article is a good counterpart to the one we published previously on the other dominant sea urchin species in the shallow Mediterranean: the purple sea urchin Paracentrotus lividus (Carreras et al 2020, available at https://onlinelibrary.wiley.com/doi/full/10.1111/ddi.13016). Both species are important ecosystem engineers. It is interesting to note the differences in population parameters of two species with similar larval lifespans, such as a more marked effect of the Almería-Oran front in the purple than in the black sea urchin. For the latter, only a clear differentiation between populations in the eastern and the western basin was detected. Salinity, rather than temperature, seems to drive adaptive responses in Arbacia lixula. Overall, the scenario of an increased dominance of the black sea urchin in a warming Mediterranean seems plausible.

Here is the abstract:

Global environmental changes may have a profound impact on ecosystems. In this context, it is crucial to gather biological and ecological information of the main species in marine communities to predict and mitigate potential effects of shifts in their distribution, abundance, and interactions. Using genotyping by sequencing (GBS), we assessed the genetic structure of a keystone species in the Mediterranean shallow littoral ecosystems, the black sea urchin Arbacia lixula. This bioengineer species can shape their communities due to its grazing activity and it is experiencing an ongoing expansion with increasing temperatures. The population genomic analyses on 5,241 loci sequenced in 240 individuals from 11 Mediterranean sampled populations revealed that all populations were diverse and showed significant departure from equilibrium. Albeit genetic differentiation was in general shallow, a significant break separated the western and eastern Mediterranean populations, a break not detected in previous studies with less resolutive markers. Notably, no clear effect of the Almería-Oran front, an important break in the Atlanto-Mediterranean transition, could be detected among the western basin populations, where only a slight differentiation of the two northernmost populations was found. Despite the generally low levels of genetic differentiation found, we identified candidate regions for local adaptation by combining different genomic analysis with environmental data. Salinity, rather than temperature, seemed to be an important driver of genetic structure in A. lixula. Overall, from a population genomics standpoint, there is ample scope for A. lixula to continue thriving and adapting in the warming Mediterranean.

 

Results of a DAPC ordination of samples, with the fitted vectors of environmental variables superimposed