Matthew effect in counting the number of species
The number of species in an area is a fundamental parameter in species-area theory. Besides sampling size and statistical extrapolation, the inaccurate number of species can intensify the existing controversy on the species richness—productivity and extinction rate overestimate/underestimate. This problem can be caused by Matthew effect from sampling process and taxonomic identification: it is much easier to identify and record common species than rare species. Therefore, it is necessary to prevent and control the Matthew effect, which can distort the number of species (especially the rare species) and the individuals of each species.