A chytrid fungus, Batrachochytrium dendrobatidis, has caused mass mortality and biodiversity loss in amphibians at El Copé, Panama. The study shows a strong correlation between the emergence of this pathogen and the decline of amphibian populations. The fungus, which causes chytridiomycosis, has led to the extinction of several amphibian species and a significant reduction in biodiversity. The disease is highly virulent and has a wide range of potential hosts, posing a threat to global amphibian diversity. The study found that the fungus was absent or present at very low levels before September 2004, but its prevalence increased dramatically, leading to widespread mortality and local population extinctions. The disease was confirmed through histological and molecular analyses, and Koch's postulates were fulfilled, demonstrating that the fungus is the primary cause of the observed die-offs. The study highlights the role of emerging infectious diseases in amphibian population declines and suggests that chytridiomycosis is a major driver of amphibian extinctions. The disease spreads through both direct and environmental transmission, and its prevalence can increase rapidly in amphibian communities. The study also notes that the disease is likely to spread further in the Neotropics, leading to more amphibian extinctions. The research underscores the importance of understanding the ecology and evolution of infectious diseases in the context of biodiversity loss. It also emphasizes the need for further study to understand the long-term impacts of chytridiomycosis on amphibian populations and the factors that contribute to its spread. The findings suggest that amphibian declines are not merely due to sampling or natural fluctuations but are often caused by pathogens like B. dendrobatidis. The study concludes that chytridiomycosis is a significant threat to amphibian biodiversity and highlights the need for conservation efforts to mitigate its impact.A chytrid fungus, Batrachochytrium dendrobatidis, has caused mass mortality and biodiversity loss in amphibians at El Copé, Panama. The study shows a strong correlation between the emergence of this pathogen and the decline of amphibian populations. The fungus, which causes chytridiomycosis, has led to the extinction of several amphibian species and a significant reduction in biodiversity. The disease is highly virulent and has a wide range of potential hosts, posing a threat to global amphibian diversity. The study found that the fungus was absent or present at very low levels before September 2004, but its prevalence increased dramatically, leading to widespread mortality and local population extinctions. The disease was confirmed through histological and molecular analyses, and Koch's postulates were fulfilled, demonstrating that the fungus is the primary cause of the observed die-offs. The study highlights the role of emerging infectious diseases in amphibian population declines and suggests that chytridiomycosis is a major driver of amphibian extinctions. The disease spreads through both direct and environmental transmission, and its prevalence can increase rapidly in amphibian communities. The study also notes that the disease is likely to spread further in the Neotropics, leading to more amphibian extinctions. The research underscores the importance of understanding the ecology and evolution of infectious diseases in the context of biodiversity loss. It also emphasizes the need for further study to understand the long-term impacts of chytridiomycosis on amphibian populations and the factors that contribute to its spread. The findings suggest that amphibian declines are not merely due to sampling or natural fluctuations but are often caused by pathogens like B. dendrobatidis. The study concludes that chytridiomycosis is a significant threat to amphibian biodiversity and highlights the need for conservation efforts to mitigate its impact.