麻豆淫院

Meerkats genetically adapt to a species-specific form of tuberculosis according to a long-term study by an international research team led by Ulm University. The scientists also found that climate change in the Kalahari Desert exerts additional selection pressure on the animals. The combination of infection pressure and climate change is putting meerkats under increasing evolutionary stress. The study's results have been in Nature Ecology & Evolution.

How do wild animal diseases affect the genetics of their hosts in the long term鈥攁nd what is the role of climate change? A team of researchers from Germany, Switzerland, the United Kingdom and Australia, led by Professor Simone Sommer from the Institute of Evolutionary Ecology and Conservation Genomics at Ulm University, investigated this using genetic data collected over two decades from more than 1,500 meerkats, together with data on the spread of tuberculosis.

The researchers were able to show for the first time that the disease alters the immune-genetic diversity of the animals. The tuberculosis infection, which is caused by the bacterium Mycobacterium suricattae, greatly shortens the life expectancy of meerkats and makes it more difficult for them to reproduce.

The study focuses on the so-called MHC genes (Major Histocompatibility Complex), which play an important role in the recognition of pathogens and the immune defense of all vertebrates. The researchers made a surprising discovery: Over the course of the study, a certain gene variant developed from a supposed risk factor into a survival advantage. While this variant was initially more common in infected animals, adaptation processes in wild animals later led to a longer life and more offspring鈥攁 clear indication of dynamic selection processes triggered by pathogens.

"Our data impressively shows how infectious diseases can trigger evolutionary changes in wild animal populations in real time," explains Dr. Nadine M眉ller-Klein, first author of the study and scientist at the Institute of Evolutionary Ecology and Conservation Genomics. Until now, such adaptations had mainly been hypothesized on the basis of laboratory studies.

Climate change increases spread of tuberculosis

Particularly alarming: climatic changes, especially rising temperatures and changes in rainfall combined with heat waves, significantly increase the spread and progression of tuberculosis. The results emphasize the growing importance of wildlife diseases in the context of global warming.

"Climate change is not only altering habitats, but also the way in which infectious diseases affect the health of wild animals," explains Ulm co-author Dr. Dominik Melville. "Lack of food and heat stress deplete energy reserves鈥攚hich is particularly critical when an animal is already weakened or infected."

Professor Sommer adds, "Twenty years ago, we already realized that preserving genetic diversity would be crucial for species conservation. Now we recognize how immunogenetic diversity in particular plays a central role鈥攊t can significantly reinforce the disease resilience of wild animals in the face of climate change."

The study also shows positive prospects for them. At the same time, the wildlife ecologist warns, "The results emphasize the need to consider genetic diversity as an integral part of modern species conservation strategies."

The findings of this study do not only concern meerkats. They significantly contribute to fundamental research in evolutionary biology, while also providing important impetus for wildlife health and conservation strategies in the face of climate change.

The study was made possible by the extensive collection of data from one of the world's best documented wildlife populations in the Kuruman River Reserve in the Kalahari and decades of research led by Professor Marta Manser from the University of Zurich and Professor Tim Clutton-Brock from the University of Cambridge.