Dataset Information

Narrow thermal tolerance and low dispersal drive higher speciation in tropical mountains.

ABSTRACT: Species richness is greatest in the tropics, and much of this diversity is concentrated in mountains. Janzen proposed that reduced seasonal temperature variation selects for narrower thermal tolerances and limited dispersal along tropical elevation gradients [Janzen DH (1967) Am Nat 101:233-249]. These locally adapted traits should, in turn, promote reproductive isolation and higher speciation rates in tropical mountains compared with temperate ones. Here, we show that tropical and temperate montane stream insects have diverged in thermal tolerance and dispersal capacity, two key traits that are drivers of isolation in montane populations. Tropical species in each of three insect clades have markedly narrower thermal tolerances and lower dispersal than temperate species, resulting in significantly greater population divergence, higher cryptic diversity, higher tropical speciation rates, and greater accumulation of species over time. Our study also indicates that tropical montane species, with narrower thermal tolerance and reduced dispersal ability, will be especially vulnerable to rapid climate change.

SUBMITTER: Polato NR

PROVIDER: S-EPMC6298121 | biostudies-literature | 2018 Dec

REPOSITORIES: biostudies-literature

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Narrow thermal tolerance and low dispersal drive higher speciation in tropical mountains.

Polato Nicholas R NR Gill Brian A BA Shah Alisha A AA Gray Miranda M MM Casner Kayce L KL Barthelet Antoine A Messer Philipp W PW Simmons Mark P MP Guayasamin Juan M JM Encalada Andrea C AC Kondratieff Boris C BC Flecker Alexander S AS Thomas Steven A SA Ghalambor Cameron K CK Poff N LeRoy NL Funk W Chris WC Zamudio Kelly R KR

Proceedings of the National Academy of Sciences of the United States of America 20181105 49

Species richness is greatest in the tropics, and much of this diversity is concentrated in mountains. Janzen proposed that reduced seasonal temperature variation selects for narrower thermal tolerances and limited dispersal along tropical elevation gradients [Janzen DH (1967) <i>Am Nat</i> 101:233-249]. These locally adapted traits should, in turn, promote reproductive isolation and higher speciation rates in tropical mountains compared with temperate ones. Here, we show that tropical and temper ...[more]

PMID: 30397141

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Dataset Information

Narrow thermal tolerance and low dispersal drive higher speciation in tropical mountains.

Publications

Narrow thermal tolerance and low dispersal drive higher speciation in tropical mountains.

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