Population loss and genetic diversity: parts of the biodiversity conservation puzzle
Environmental change isn’t only causing a significant decrease in biodiversity, it’s also impacting genomic diversity. “In the current ecological crisis, wildlife populations are facing rapid declines and are at risk of losing genetic diversity,” says Hernán Morales, a researcher at the University of Copenhagen. According to Morales, genetic diversity provides the substrate for adaptation and population viability. “A thorough understanding of how genetic diversity changes in the face of population decline is thus an essential piece of the biodiversity conservation puzzle,” he explains. Helping provide this understanding is the EU-funded GENDANGERED project.
From samples to computer modelling
Together with Tom Gilbert, a professor at the University of Copenhagen, along with museums, organisations and research groups, Morales examined several endangered bird species that have seen their populations plummet in recent decades. “We sequenced the genomes of both old and contemporary samples, directly comparing the genetic diversity before and after the population decline,” remarks Morales. While getting the necessary samples from natural history collections was delayed due to the COVID-19 pandemic, this didn’t stop Morales from continuing his research. “I focused on the computer modelling part of the project, which actually turned out to be a great experience as I was able to learn more at a greater level of detail,” he adds.
Forecasting the long-term viability of a species
Using the computer models, researchers obtained an in-depth look at how genomic diversity changes over time in response to habitat degradation and a loss of population. “We discovered that genetic diversity’s response to population decline largely depends on a species’ past demography, their level of connectivity, and the amount of conservation management they were subjected to,” notes Morales. Morales goes on to explain that genetic variation can have either a positive, negative or neutral effect on a species’ viability, with neutral variation being particularly important, as it can fuel future adaptive change. “Our research shows that any decrease in population will reduce the positive and neutral genetic variants and elevate the negative ones, resulting in an increase in harmful variation,” he adds. “Over time, this could compromise the long-term viability of a species.”
Informing conservation efforts
The GENDANGERED project, which was undertaken with the support of the Marie Skłodowska-Curie Actions programme, has helped position the use of fundamental evolutionary genomic sciences within biodiversity conservation. Some of the project’s findings will inform the conservation efforts of the endangered species monitoring programmes that contributed to projects happening at the Australian National University, International Crane Foundation, Mauritian Wildlife Foundation and Durrell Wildlife Conservation Trust. Morales will also lean on the project’s findings as a member of the Conservation Genetics Specialist Group, part of the International Union for Conservation of Nature. “This group is making fantastic efforts to incorporate genetic information directly into conservation policy and I’m excited to add GENDANGERED’s findings into this initiative,” he says. Although the project itself is now finished, Morales’ work continues. “There are many directions that I want to take this research,” he concludes. “This includes exploring how we can increase the use of computer models to empower conservation practitioners.”
Keywords
GENDANGERED, wildlife, genetic diversity, population loss, biodiversity, conservation, endangered species, computer modelling, habitat degradation
