Scale affects the understanding of biases on the spatial knowledge of Atlantic Forest primates

[Display omitted] •Spatial knowledge of Atlantic Forest primates has biases that vary according to the study scale and grid cell resolution;•In broad-scale perspectives (regional and global) the primate’s spatial knowledge is unbiased;•At narrow-scale perspectives, the knowledge may have bias, depending on grid cell resolution;•The central region of the Atlantic Forest is well sampled;•The São Francisco region and ecotone zones need to be further sampled. The biodiversity knowledge has several deficits. The wallacean shortfall—related to species distribution unknowledge—is one of the most studied shortfalls. It is important to identify gaps and biases in spatial biodiversity knowledge. However, to find out where the main biodiversity deficits are we need to know how the biodiversity spatial sampling changes according to spatial scale. Here we use an extensive dataset of Atlantic Forest primates to test spatial bias as a function of spatial scales and cell-size resolutions. Our findings indicate that the sampling coverage and spatial knowledge of Atlantic Forest primates are biased depending on spatial cell-size resolution and scale. We also show that from a broad-scale perspective (regional and global) primate spatial knowledge is spatially unbiased regardless of cell-size resolution considered. In contrast, in narrow-scale perspectives the knowledge may have or not spatial bias depending on the cell-size resolution. Our results suggest that sampling bias can be present or more pronounced in narrow-scale in a local perspective. Thus, the choice of scale and spatial resolution on ecological studies must consider the potential impacts of sampling bias accordingly to each scale and cell-size resolution.