Figure 1.
Filtered occurrences of L. camara used for this study.
Table 1.
Biodiversity databases used to obtain occurrences of L. camara.
Figure 2.
Niche dynamics of Lantana camara: from native to invaded ranges.
The contour lines delineate the available niche in its native range (green) and in its invaded range (red) in India (column a), Australia (column b) and Africa (column c). The solid and dashed contour lines illustrate, respectively, 100% and 50% of the available (background) environment. The colored areas correspond to the unfilled zone (green; line 1), the overlap zone (blue; line 2), or the expansion zone (red; line 3) resulting from overlaying the native niche with the invaded niche. The last line shows the correlation circles, which indicate the weight of each bioclimatic variable on the niche space defined by the first two principal component axes. The predictor climatic variables are BIO1 (annual mean temperature), BIO5 (temperature of warmest month), BIO12 (annual precipitation), BIO14 (precipitation of driest month), BIO15 (precipitation seasonality), BIO18 (precipitation of warmest quarter).
Table 2.
Niche dynamics values estimated using climatic conditions in the native and invaded regions.
Figure 3.
Statistical tests for niche comparisons between native and invaded regions.
Observed frequencies for the niche overlap index (D) in relation to the expected D for p = 0.05. The first line shows the tests for niche equivalency (a, b and c) and the second line for niche similarity (d, e, and f). The first column compares niches between the native range and Australia (a and d), the second column between the native range and Africa (b and e) and the third column between the native range and India (c and f).
Table 3.
Evaluation index values (AUC and Boyce Index) and omission rate for the obtained models.
Figure 4.
Potential geographic distribution of L. camara in its native region.
Predictions are based on current occurrences in the Neotropics and the climatic data from the places where this plant inhabits there.
Figure 5.
Potential geographic distributions of L. camara in each invaded region.
The first line shows the predicted geographic distributions in Africa (a, d), the second line in India (b, e) and the third in Australia (c, f). The first column illustrates predictions based on invaded-to-invaded projections (a, b, c), and the second column based on native-to-invaded projections (d, e, f).
Figure 6.
New potentially invadable areas resulting from the observed niche shift in India.
Overlay of the potential geographic distributions in Africa (a) and Australia (b) estimated from the native niche and the modified niche in India. The orange areas identify new vulnerable areas. They correspond to locations predicted as unsuitable according to its current distribution in its native range, but as suitable based on its current distribution in India.
Table 4.
Percent overlap, unfilled and expansion areas in Australia, Africa and India obtained by overlaying the native-to-invaded distributions with the invaded-to-invaded distributions in each invaded region.
Table 5.
Percent unfilled and expansion areas in Australia and Africa obtained by overlaying the modified-niche-to-invaded distributions with the invaded-to-invaded distributions in both invaded region.
Figure 7.
Climatic analogy between the native range of L. camara and its invaded range in India.
Using the multivariate environmental similarity surface (MESS) we identified BIO1 (annual mean temperature), BIO18 (precipitation of the warmest quarter) and BIO5 (temperature of the warmest month) as the most dissimilar variables. The red, blue and yellow areas identify locations in India with values for BIO5, BIO1 and BIO18, respectively, outside the observed value range in its native region.
Figure 8.
Differences in maximum temperature of the warmest month between the native range of L. camara and its invaded range in India.
The mean values and their standard errors were estimated using the temperature of the warmest month at each location where this plant is present in India and in its native range.