Trait-based prediction of extinction risk

Biological diversity is eroding at an increasing pace and most probably more species fall into extinction than are described every single day. Useful knowledge for the conservation of most species is extremely scarce and the current population trends for most of them are unknown. Identifying ecological or functional trait characteristics of species that are the ultimate causes of extinction may be extremely useful to circumvent the lack of knowledge on species trends. In this project, our aim was to identify which are the biological traits (like body size, diet) of species that make them more prone to becoming extinct. To identify such traits, we employ two approaches. The theoretical approach aimed to understand the underlying mechanisms governing the relationship between a given trait (for example, body size) and extinction risk. In this approach, we created "virtual" species, or artificial species, which were all similar to each other except in the focus trait and simulated different threatening scenarios (like habitat loss or hunting) to see which will be the winner. In the empirical approach, the objective is not to understand mechanisms, but rather to find real evidence of correlations between biological traits and extinction risk, for that crossing real species and their known biological traits with threat status. Two key messages emerged from this work: species with narrow habitat and climatic breadth, poor fecundity, poor capacity to disperse, and high degree of human disturbance within the geographical range are more threatened to extinction. However, our simulations suggested that the same trait can be disadvantageous under certain human threats, but advantageous in others.