Login   |   Register


Evolution in action across life at “Evolution Canyons”, Israel

Eviatar Nevo

Authors information

Abstract


The "Evolution Canyon" model reveals evolution in action across life at a microscale involving biodiversity divergence, adaptation and incipient sympatric ecological speciation across life. The model highlights diverse taxa species richness, genomics, proteomics and phenomics phenomena by exploring genetic polymorphisms at protein and DNA levels and, recently, genome-wide gene expression and regulation. Genetic diversity and divergence reveal evolutionary dynamics of natural populations exposed to sharp-interslope, ecologically divergent, tropical and temperate microclimates on a xeric, tropical, "African" south-facing slope (AS) abutting with a mesic, temperate, "European" north-facing slope (ES) separated by 200 meters on average. Four "Evolution Canyons” (EC) are currently being investigated in Israel in the Carmel, Galilee, Negev, and Golan Mountains (EC I-IV), respectively. We identified 2,500 species in ECI (Carmel) from bacteria to mammals in an area of 7,000 m2. Local biodiversity patterns parallel global patterns. Higher terrestrial species richness was found on the AS. Aquatic species richness prevails on the ES. In 9 out of 14 (64%) model organisms across life, we identified a significantly higher genetic polymorphism on the more stressful AS. Likewise, in some model taxa, we found largely higher levels of mutation rates, gene conversion, recombination, DNA repair, genome size, small sequence repeats (SSRs), single nucleotide polymorphism (SNPs), retrotransposons, transposons, candidate gene diversity, and genome-wide gene expression and regulation on the more stressful AS. Remarkably, interslope incipient sympatric ecological speciation was found across life from bacteria to mammals. The "Evolution Canyon" model represents the Israeli ecological analogue of the Galapagos Islands. Micro- climatic selection overrides gene flow and drift, and drives both interslope adaptive divergence and incipient sympatric ecological speciation at a microscale. The EC model could potentially highlight many mysteries of evolutionary biology including the genetic basis of adaptation and speciation, especially now with the rapid high-throughput techniques of whole genome analysis.

Keywords


Biodiversity evolution, species richness, microclimatic divergent selection, active evolution, adaptive divergence, sympatric ecological speciation

Full Text





Submitted: 2009-05-05 14:41:57
Published: 2009-10-16 13:10:00
Search for citations in Google Scholar
Related articles: Google Scholar


 

FOOTER

Trends in Evolutionary Biology [eISSN 2036-265X] is an Open Access, peer-reviewed journal published by PAGEPress, Pavia, Italy. All credits and honors to PKP for their OJS.

 
 
© PAGEPress 2008-2014     -     PAGEPress is a registered trademark property of PAGEPress srl, Italy.     -     VAT: IT02125780185