Sequencing reveals complex history of amphibian-killing fungus
(Phys.org) —One of the biggest threats facing amphibian species is the disease chytridiomycosis, which is caused by a fungus known as Batrachochytrium dendrobatidis (Bd). An understanding of the evolutionary history of microbial pathogens, like Bd, is critical to predicting disease outbreaks and causes of shifts in virulence. The sudden appearance of Bd worldwide suggests a recent introduction into the affected areas, likely facilitated by the international movement of amphibians. A new paper published yesterday in PNAS reveals that the evolutionary history of Bd significantly predates recent outbreaks, and is much deeper and more complex than previously thought. Using whole-genome sequencing from a global panel of Bd isolates, researchers suggest that Bd likely originated somewhere between 10,000 and 40,000 years ago, but could be as old as 100,000 years.