Change of niche in guanaco (Lama guanicoe): The effects of climate change on habitat suitability and lineage conservatism in Chile
- Published
- Accepted
- Subject Areas
- Biogeography, Conservation Biology, Evolutionary Studies, Taxonomy, Climate Change Biology
- Keywords
- Environmental Niche Modelling, Climate Change, Lama, Ungulate conservation, maxent
- Copyright
- © 2018 Castillo et al.
- Licence
- This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ Preprints) and either DOI or URL of the article must be cited.
- Cite this article
- 2018. Change of niche in guanaco (Lama guanicoe): The effects of climate change on habitat suitability and lineage conservatism in Chile. PeerJ Preprints 6:e3517v1 https://doi.org/10.7287/peerj.preprints.3517v1
Abstract
Background. A fundamental problem in the biogeography of climate change is to understand and predict how environmental factors determine whether organisms will alter their seasonal activities, home ranges, migratory patterns, abundances, and interspecific interactions. The main goal of this contribution was to define the ecological niche of the guanaco (Lama guanicoe) to describe potential distributional changes and to assess the relative importance of niche conservatism and divergence processes among the two lineages described for the species.
Methods. We used current and future projections of climate change under two extreme GHG emission scenarios (RCP2.6 and RCP8.5) to evaluate changes of the environmental niche and future distribution of the largest mammal in the southern cone of South America. Evaluation of niche conservatism and divergence are based on identity and background similarity tests.
Results. We show that: a) the current geographic distribution of lineages and contact population prescribe different climatic requirements that are related to the geographic areas where these lineages are located; b) future distribution models predict a decrease in the distribution surface under both scenarios; c) the surface area predicted to be gained, lost, and unchanged is ~15%, 15- 26%, and 85- 75% respectively; d) a 3% increase of areal protection is expected if the current distribution of protected areas is maintained, however this is expected to occur at the expense of a large reduction of high quality habitats under the best scenario and; e) current and future distribution ranges of guanaco mostly adhere to phylogenetic niche divergence hypotheses between linages (L. g. cacsilensis and L. g. guanicoe). However, both lineages and the contact population show niche conservatism given niche similarity tests.
Discussion. Associating environmental variables to species ecological niche seem to be an important aspect of unveiling the particularities of, both, evolutionary patterns and ecological features that species face in a changing environment. We have provided specific descriptions of how such patterns may play out under the most extreme climate change predictions, thereby, providing a grim outlook of the future potential distribution of guanaco. From an ecological perspective, while a slightly larger distribution area is expected, this may come with an important reduction of available quality habitats. From the evolutionary perspective, we describe the limitations of the contact population´s niche to merge with the northern and/or southern niche lineages of guanaco exposing the complexities of understanding evolutionary patterns across this taxon as it experiences climate change dynamics.
Author Comment
This is a submission to PeerJ for review.
Supplemental Information
Map of differences between methodologic models
This is the predictive mapping for both methods used in this work. Panel (A) forecast-model 1 product of the average of models under different GCMs, Panel (B) forecast-model 2 product the bioclimatic variables averaged under the different GCMs. Here we have subtracted the panel prediction (B) on panel (A). In panel (C) the differences in the predictions of both forecast models are observed, the red areas indicate overestimation of the distribution of L. guanicoe, and blue zones indicate an underestimation of this distribution.
Pairwise correlation values from bioclimatic variables
BIO1: Annual mean temperature; BIO4: Temperature seasonality; BIO7: Temperature annual range; BIO12: Annual precipitation; BIO15: Precipitation seasonality
Principal component analysis of bioclimatic variables
Biplot of principal component from a bioclimatic variables final set. Where BIO1: Annual mean temperature; BIO4: Temperature seasonality; BIO7: Temperature annual range; BIO12: Annual precipitation; BIO15: Precipitation seasonality.
Area Under the Curve (AUC) Jackknife analysis of environmental variables
AUC Jackknife analysis for the environmental variables used in the current distribution models generation of each guanaco lineage in Chile. Bio1 = Annual mean temperature; Bio4 = Temperature seasonality; Bio7 = Temperature annual range; Bio12 = Annual precipitation Bio15 = Precipitation seasonality.