El declive de los anfibios. La dificultad de separar las variaciones naturales del cambio global

摘要: SUMMARY World-wide crisis of biodivesity can be attributable, in first place, to direct impact human activities on the environment, and their effects are objectively noticeable. On other hand, global climate changes induced indirectly by may also explain this but consequences difficult evaluate since they confounded with natural fluctuations populations. Amphibian populations have been suspected declining globally, an increasing number studies shown that many species disappearing even from seemingly pristine habitats, especially tropical montane sites where interferences disregarded as a potential cause decline. This suggests idea agents responsible these losses. However, rigorous evaluation hypothesis would previously require demonstrate existence pattern amphibian Studies addressing question certainly not conclusive enough long-term census data amphibians still available. Most exhibit high degree demographic variability clouds any conclusion about trends. limitation precludes possibility drawing decline when based time series too short statistical power reject null no Some alternatives monitoring programs suggested such elasticity analysis molecular tests for eventual population bottlenecks.