Temporal changes in the potential geographic distribution of Histiotus velatus (Chiroptera, Vespertilionidae), the “decade effect"

Also investigate how the potential distribution of this species changes
with the addition of new records over the decades (decade effect).
Assuming that (1: hypothesis of the effect of the decade) the addition of
new occurrence records over time increases the potential size of the
species distribution; and (2: Wallacean distance hypothesis) over the
years, the new points added are increasingly distant from the research
centers. Considering the geographic knowledge gap of Histiotu velatus, our
objective is to report a new record of this species and estimate its
potential distribution in South America through ENMs. For this, we
compiled records of occurrence of species, selected from 1900 to 2015. We
used 19 bioclimatic variables available in the WorldCLim database to
estimate the potential distribution of the species and we used three
modeling algorithms: Maximum Entropy (MXT) Random Forest (RDF) and Support
Vector Machine (SVM). We selected the main bat research centers in Brazil,
using the Lattes platform for the Wallacean distance hypothesis, using the
Euclidean distance calculation. To test the hypothesis of the decade
effect, we used beta regression analysis, taking conservative and
non-conservative approaches. The results showed that the predicted area
expanded and retracted over the decades, with an improvement in the
accuracy of the models with the addition of new data. Most of the records
are located in the southeastern region of Brazil, but the algorithms
predicted areas in countries where there were no records. Only the
conservatism approach has had a positive relationship over the decades.
The distance from new points does not increase over the years of research
centers.