Environmental variables
To investigate the importance of our environmental variables in
determining species presence, we compared rescaled, standardized
values of the environmental variables at locations where the
species was predicted present or absent. To do this, we overlapped
the layer of the single binary ensemble with the nine environmental
variables used in the modeling. For each variable, we
extracted the value for each pixel at which the species was
predicted present or not present. To compare niche dimensions,
we converted all variables to the same scale, such that the values
from the whole study area ranged between 0 and 1. We assume
that the most limiting variable for species occurrence is the one
with the smallest standard deviation for predicted presence and
with the greatest difference between the means of predicted
present and not present.
To complement the previous analysis, we overlapped the maned
sloth 42 occurrence points with the nine environmental variables
used in the modeling, and extracted the value for each pixel. Then
we performed a principal component analysis (PCA) to associate
the maned sloth occurrence points records to the environmental
variables, aiming to provide the means to explain the variance
magnitudes related to environmental variables to reveal the
internal structure of the data. This technique is used to represent,
in the environmental space, the niche occupied by the species