Patterns of persistence and isolation indicate resilience to climate change in montane rainforest lizards

Date

2010

Authors

Bell, Rayna C.
Parra, Juan L.
Tonione, M.
Hoskin, Conrad
MacKenzie, Jacob B.
Williams, Stephen E.
Moritz, Craig

Journal Title

Journal ISSN

Volume Title

Publisher

Blackwell Publishing Ltd

Abstract

Globally, montane tropical diversity is characterized by extraordinary local endemism that is not readily explained by current environmental variables indicating a strong imprint of history. Montane species often exist as isolated populations under current climatic conditions and may have remained isolated throughout recent climatic cycles, leading to substantial genetic and phenotypic divergence. Alternatively, populations may have become contiguous during colder climates resulting in less divergence. Here we compare responses to historical climate fluctuation in a montane specialist skink, Lampropholis robertsi, and its more broadly distributed congener, L. coggeri, both endemic to rainforests of northeast Australia. To do so, we combine spatial modelling of potential distributions under representative palaeoclimates, multi-locus phylogeography and analyses of phenotypic variation. Spatial modelling of L. robertsi predicts strong isolation among disjunct montane refugia during warm climates, but with potential for localized exchange during the most recent glacial period. In contrast, predicted stable areas are more widespread and connected in L. coggeri. Both species exhibit pronounced phylogeographic structuring for mitochondrial and nuclear genes, attesting to low dispersal and high persistence across multiple isolated regions. This is most prominent in L. robertsi, for which coalescent analyses indicate that most populations persisted in isolation throughout the climate cycles of the Pleistocene. Morphological divergence, principally in body size, is more evident among isolated populations of L. robertsi than L. coggeri. These results highlight the biodiversity value of isolated montane populations and support the general hypothesis that tropical montane regions harbour high levels of narrow-range taxa because of their resilience to past climate change.

Description

Keywords

Keywords: mitochondrial DNA; animal; article; Australia; biological model; cell nucleus; classification; climate change; DNA sequence; genetic variability; genetics; geography; lizard; phylogeny; Animals; Australia; Cell Nucleus; Climate Change; DNA, Mitochondrial; Lampropholis; Lineage divergence; Montane tropical diversity; Pleistocene refugia

Citation

Source

Molecular Ecology

Type

Journal article

Book Title

Entity type

Access Statement

License Rights

Restricted until

2037-12-31