Nav: Home

Evolution in action: How some fish adapt to pollutants

December 08, 2016

New genetic analyses of fish reveal how some have managed to evolve and adapt to live in polluted water. The results suggest that the high genetic diversity exhibited by these fish was key - a palette for natural selection to act on to facilitate the population's rapid adaptation to extreme pressures. In salt marshes along North America's Atlantic coast, killifish have increasingly been exposed to industrial pollutants that have reached lethal levels in recent decades. Some subpopulations have developed tolerance to the pollutants, however. To better understand this adaptation, Noah M. Reid et al. analyzed the genomes of 384 killifish, some of which have developed tolerance to toxins and some of which remained sensitive, across four regions. Tolerant fish were found to have reduced genetic diversity compared to sensitive fish - a sign of reduction in population size in polluted sites, where exchange of genetic information became limited. The researchers also identified in these fish a number of genes that were associated with increased survival, particularly genes involved in the aryl hydrocarbon receptor (AHR) signaling pathway. By examining this pathway in developing embryos exposed to toxins, the team found that many genes associated with the AHR pathway were deleted in tolerant killifish, likely impacting AHR signaling in a manner not observed in sensitive killifish. But as the AHR pathway is associated with estrogen and hypoxia signaling, regulation of cell cycle, and immune system function, what about the consequences of it being stifled? The authors identified several compensatory mutations that may help mitigate the loss of function in AHR signaling in killifish. These results are featured in a Perspective by Michael Tobler and Zachary W. Culumber.

American Association for the Advancement of Science

Related Natural Selection Articles:

Genomic selection in dairy cows creates opportunities not possible with traditional selection
The 2019 ADSA Annual Meeting featured the Joint ADSA/Interbull Breeding and Genetics Symposia titled ''Ten Years of Genomic Selection'' and ''Data Pipelines for Implementation of Genomic Evaluation of Novel Traits.'' Because of genomic selection's importance to dairy science, the Journal of Dairy Science invited the speakers to submit articles and share information from these symposia with a wider audience.
Recurrent genomic selection for wheat grain fructans
Development of Climate-Resilient, Nutritionally Improved Wheat
NASA's OSIRIS-REx in the midst of site selection
After a lengthy and challenging process, the team is finally ready to down-select from the four candidate sites to a primary and backup site.
The argument for sexual selection in bacteria
The evolutionary pressure to pass on DNA can produce behavior that otherwise makes no sense in a struggle to survive.
Sexual selection influences the evolution of lamprey pheromones
In 'Intra- and Interspecific Variation in Production of Bile Acids that Act As Sex Pheromones in Lampreys,' published in Physiological and Biochemical Zoology, Tyler J.
Infection biology: Signs of selection in the stomach
Helicobacter pylori, a globally distributed gastric bacterium, is genetically highly adaptable.
Study finds natural selection favors cheaters
Natural selection predicts that mutualisms -- interactions between members of different species that benefit both parties -- should fall apart.
Natural selection and spatial memory link shown in mountain chickadee research
Chickadees with better learning and memory skills, needed to find numerous food caches, are more likely to survive their first winter, a long-term study of mountain chickadees has found.
Birds-of-paradise genomes target sexual selection
Researchers provide genome sequences for 5 birds-of-paradise species: 3 without previous genome data and 2 with improved data.
How much are we learning? Natural selection is science's best critic
Even as they've struggled to highlight parts of the human genome worth investigating, scientists have wondered how much they're actually learning through the methods they use.
More Natural Selection News and Natural Selection Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Clint Smith
The killing of George Floyd by a police officer has sparked massive protests nationwide. This hour, writer and scholar Clint Smith reflects on this moment, through conversation, letters, and poetry.
Now Playing: Science for the People

#562 Superbug to Bedside
By now we're all good and scared about antibiotic resistance, one of the many things coming to get us all. But there's good news, sort of. News antibiotics are coming out! How do they get tested? What does that kind of a trial look like and how does it happen? Host Bethany Brookeshire talks with Matt McCarthy, author of "Superbugs: The Race to Stop an Epidemic", about the ins and outs of testing a new antibiotic in the hospital.
Now Playing: Radiolab

If former Minneapolis police officer Derek Chauvin's case for the death of George Floyd goes to trial, there will be this one, controversial legal principle looming over the proceedings: The reasonable officer. In this episode, we explore the origin of the reasonable officer standard, with the case that sent two Charlotte lawyers on a quest for true objectivity, and changed the face of policing in the US. This episode was produced by Matt Kielty with help from Kelly Prime and Annie McEwen. Support Radiolab today at