Disentangling the effects of evolutionary and ecological processes on population growth

Climate change and human activities can strongly impact wild populations, which may need to acclimate, adapt through genetic changes, or move to more suitable habitats to persist. However, these ecological and evolutionary processes are rarely studied simultaneously, which can lead to biases when evaluating the vulnerability of populations to environmental changes. The DEEP-Pop project bridges the fields of ecology, evolution, and genomics in a unified quantitative framework to better understand how wild Atlantic salmon populations respond to environmental changes. By studying 150 populations over a 30-year period, we first aim to describe changes in the number of Atlantic salmon and identify the environmental drivers affecting population dynamics. We will then investigate the effect of these environmental drivers on the genetic composition of salmon populations and determine whether they are adapted to their current environment. By using temporal genomic data, we will gain a good understanding of which genes are contributing to the evolution of populations and their impact on population growth. Overall, the DEEP-Pop project seeks to unveil whether diverse salmon populations exhibit uniform responses to environmental changes concerning genetic adaptation, migration, phenotypic variation and population growth. This multidisciplinary approach will provide valuable knowledge for understanding how species adapt to an ever-changing world.

Understanding how populations respond to changing environmental conditions is a major concern in ecology and evolutionary biology. To persist in altered environments, populations may need to acclimate (e.g. phenotypic plasticity), adapt through genetic changes or move to more suitable habitats. However, those ecological and evolutionary processes are rarely studied simultaneously, which can lead to biases when evaluating the vulnerability of populations to environmental changes. The DEEP-Pop project bridges the fields of ecology, evolution, and genomics in a unified quantitative framework to better understand how wild Atlantic salmon populations respond to environmental changes. By studying 150 populations over a 30-year period, we will first identify the environmental variables influencing Atlantic salmon demography. Then, we will investigate the genetic composition of populations to determine whether they are adapted to their current environment and how they may respond to future climatic conditions. We will investigate the potential causes of maladaptation (i.e. population size, migration, introgression of farmed salmon). By using temporal genomic data, we will get a good understanding of which genes are currently evolving and of their impact on population growth. We will be able to determine whether salmon populations respond in the same way to environmental changes, in terms of genetic changes, traits variation and population growth.