Mountain colonisation, miniaturisation and ecological evolution in a radiation of direct developing New Guinea Frogs (Choerophryne, Microhylidae)
- Published
- Accepted
- Subject Areas
- Biodiversity, Biogeography, Taxonomy
- Keywords
- Central Cordillera, endemism, montane cradle, montane museum, North Papuan Mountains, terrestrial
- Copyright
- © 2017 Oliver 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
- 2017. Mountain colonisation, miniaturisation and ecological evolution in a radiation of direct developing New Guinea Frogs (Choerophryne, Microhylidae) PeerJ Preprints 5:e2663v2 https://doi.org/10.7287/peerj.preprints.2663v2
Abstract
Aims. Mountain ranges in the tropics are characterised by high levels of localised endemism, often-aberrant evolutionary trajectories, and some of the world’s most diverse regional biotas. Here we investigate the evolution of montane endemism, ecology and body size in a clade of direct-developing frogs (Choerophryne, Microhylidae) from New Guinea. Methods. Phylogenetic relationships were estimated from a mitochondrial molecular dataset using Bayesian and maximum likelihood approaches. Ancestral state reconstruction was used to infer the evolution of elevational distribution, ecology (indexed by male calling height), and body size, and phylogenetically corrected regression was employed to examine the relationships between these three traits. Results. We obtained strong support for a monophyletic lineage comprising the majority of taxa sampled. Within this clade we identified one subclade that appears to have diversified primarily in montane habitats of the Central Cordillera (> 1000 m. a.s.l), with subsequent dispersal to isolated North Papuan Mountains. A second subclade (characterised by moderately to very elongated snouts) appears to have diversified primarily in hill forests (< 1000 m a.s.l.), with inferred independent upwards colonisations of isolated montane habitats, especially in isolated North Papuan Mountains. We found no clear relationship between extremely small body size (adult SVL less than 15mm) and elevation, but a stronger relationship with ecology – smaller species tend to be more terrestrial. Conclusions. Orogeny and climatic oscillations have interacted to generate high montane biodiversity in New Guinea via both localised diversification within montane habitats (centric endemism) and periodic dispersal across lowland regions (eccentric endemism). The correlation between extreme miniaturisation and terrestrial habits reflects a general trend in frogs, suggesting that ecological or physiological constraints limit niche usage by miniaturised frogs, even in extremely wet environments such as tropical mountains.
Author Comment
This document has undergone minor resisions since the previous version, included changes to main text, and small corrections and changes to all Figures.
Supplemental Information
Supplmentary Figures and Tables
Supplementary tables and figures. Specimens numbers, locality information and GenBank accession numbers for Choerophryne specimens included in analyses (Table S1); GenBank accession details for outgroup samples (Table S2); genetic distance data for species and candidate lineages (Table S3); and summary data on body, elevational distribution and calling height for Choerophryne (Table S4). Bayesian tree for all samples (Figure S1); Trait evolution in the major lineages of Choerophryne estimated using BEAST (Figure S2); and summary of museum records for Choerophryne grouped by phenotype (Figure S3).
Supplementary File 2
Appendix S2. BEAST input file for ancestral state analyses
Supplementary File 3
Appendix S3. Treefile for chronogram estimated in BEAST with ancestral states.