Evolution in action: adaptation and incipient sympatric speciation with gene flow across life at “Evolution Canyon”, Israel

Abstract

Various major evolutionary problems are still open, controversial or unsettled. These include even the basic evolutionary processes of adaptation and speciation. The “Evolution Canyon” model is a microscale natural laboratory that can highlight some of the basic problems requiring clarification (Nevo list of “Evolution Canyon” publications at http://evolution.haifa.ac.il). This is especially true if an interdisciplinary approach is practiced including ecological functional genomics, transcriptomics, proteomics, metabolomics and phenomics. Here I overview and reanalyze the incipient sympatric adaptive ecological speciation of five model organisms at “Evolution Canyon”, across life: the soil bacterium, Bacillus simplex; wild barley, the progenitor of cultivated barley, Hordeum spontaneum; the tiny beetle Oryzaephilus surinamensis; the cosmopolitan fruit-fly, Drosophila melanogaster, and the Africa-originated spiny mouse, Acomys cahirinus. All five models of organisms display evolution in action of microclimatic adaptation and incipient sympatric adaptive ecological speciation on the tropical and temperate abutting slopes, separated on average by only 250 meters. Some distant species converge in their micro-climatic adaptations to the hot and dry “African”, south-facing slope (SFS or AS) and to the cool and humid “European”, north-facing slope (NSF or ES). Natural selection overrules ongoing inter-slope gene-flow between the free interbreeding populations within and between slopes, and leads to adaptive incipient sympatric ecological speciation on the dramatically opposite abutting xeric savannoid and mesic forested slopes.

Keywords:

• adaptive evolution
• incipient sympatric ecological speciation

Acknowledgements

I thank all my collaborators from Israel and overseas for their excellent collaborations in the long-term “Evolution Canyon” project. I thank Kexin Li, Avigdor Beiles and Robin Permut for their help in reading and commenting on the manuscript. The Ancell-Teicher Research Foundation of Genetic and Molecular Evolution provided financial support throughout this long-term project. I extend my deepest gratitude to the Foundation. I devote this paper to my late dear friend President Joseph Teicher, a visionary leader and exemplary human being.

Additional information

Notes on contributors

Eviatar Nevo

The evolutionary biological studies of Eviatar Nevo involve genes, genomes, phenomes, populations, species, and ecosystems of bacteria, fungi, plants, animals and humans. They focus on the structure, function, and causation of genetic/genomic diversity in nature, adaptation, speciation and domestication. See publication details at http://evolution.haifa.ac.il and autobiography in the chapter titled ‘My Life: Origin and Evolution’ in the book titled The Evolution of Eibi Nevo in honor of his 80th birthday (2009).