Abstract

Species distribution models are useful for identifying the ecological characteristics that may limit a species’ geographic range and for inferring patterns of speciation. Here, we test a hypothesis of niche conservatism across evolutionary time in a group of manakins (Aves: Pipridae), with a focus on Chiroxiphia boliviana, and examine the degree of ecological differentiation with other Chiroxiphia and Antilophia manakins. We tested whether allopatric sister species were more or less similar in environmental space than expected given their phylogenetic distances, which would suggest, respectively, ecological niche conservatism over time or ecologically mediated selection (i.e. niche divergence). We modeled the distribution of nine manakin taxa (C. boliviana, C. caudata, C. lanceolata, C. linearis, C. p. pareola, C. p. regina, C. p. napensis, Antilophia galeata and A. bokermanni) using Maxent. We first performed models for each taxon and compared them. To test our hypothesis we followed three approaches: (1) we tested whether C. boliviana could predict the distribution of the other manakin taxa and vice versa; (2) we compared the ecological niches by using metrics of niche overlap, niche equivalency and niche similarity; and (3) lastly, we tested whether niche differentiation corresponded to phylogenetic distances calculated from two recent phylogenies. All models had high training and test AUC values. Mean AUC ratios were high (>0.8) for most taxa, indicating performance better than random. Results suggested niche conservatism, and high niche overlap and equivalency between C. boliviana and C. caudata, but we found very low values between C. boliviana and the rest of the taxa. We found a negative, but not significant, relationship between niche overlap and phylogenetic distance, suggesting an increase in ecological differentiation and niche divergence over evolutionary time. Overall, we give some insights into the evolution of C. boliviana, proposing that ecological selection may have influenced its speciation.

Highlights

  • ObjectivesOur goal was to understand the coarse-scale ecological and geographic properties of species’ distributions [16,17] and, as a consequence, we most closely follow the Grinnellian niche concept

  • The distributional area of a species is an expression of its evolutionary history and its ecology [1,2]

  • The present study extends the approaches followed by Anciães and Peterson [19] in four main ways: we focus on C. boliviana in comparison with other Chiroxiphia and Antilophia manakins, making it a more detailed approach; we significantly increase the sample sizes of all taxa; we add robust methods to describe and compare the ecological niches in environmental space; and we perform a correlation between niche and phylogenetic distance

Read more

Summary

Objectives

Our goal was to understand the coarse-scale ecological and geographic properties of species’ distributions [16,17] and, as a consequence, we most closely follow the Grinnellian niche concept. The overall goals of this study were to test hypotheses of niche conservatism and speciation in C. boliviana, with other Chiroxiphia and Antilophia manakins

Methods
Results
Conclusion

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.