“Evolution Canyon,” a potential microscale monitor of global warming across life

Abstract

Climatic change and stress is a major driving force of evolution. The effects of climate change on living organisms have been shown primarily on regional and global scales. Here I propose the “Evolution Canyon” (EC) microscale model as a potential life monitor of global warming in Israel and the rest of the world. The EC model reveals evolution in action at a microscale involving biodiversity divergence, adaptation, and incipient sympatric speciation across life from viruses and bacteria through fungi, plants, and animals. The EC consists of two abutting slopes separated, on average, by 200 m. The tropical, xeric, savannoid, “African” south-facing slope (AS = SFS) abuts the forested “European” north-facing slope (ES = NFS). The AS receives 200–800% higher solar radiation than the ES. The ES represents the south European forested maquis. The AS and ES exhibit drought and shade stress, respectively. Major adaptations on the AS are because of solar radiation, heat, and drought, whereas those on the ES relate to light stress and photosynthesis. Preliminary evidence suggests the extinction of some European species on the ES and AS. In Drosophila, a 10-fold higher migration was recorded in 2003 from the AS to ES. I advance some predictions that could be followed in diverse species in EC. The EC microclimatic model is optimal to track global warming at a microscale across life from viruses and bacteria to mammals in Israel, and in additional ECs across the planet.

Climate variation and change are major abiotic stresses driving life's evolution (1–22). Parmesan and Yohe (9), analyzing results for 1,700 species, showed that recent biological trends match climate-change predictions. Global meta-analyses documented significant range shifts averaging 6.1 km per decade northward (or 6.1 m per decade upward) and significant mean advancement of spring events by 2.3 d per decade. A significant globally coherent fingerprint of climate change across natural systems was identified for 289 species (9). Parmesan (7) reviewed evidence of climate change indicating that climate change is already affecting living systems in diverse perspectives, including phenological changes, species interactions, range shifts, contractions and abundance, elevation shifts, marine communities’ shifts, pest and disease shifts, tree-line patterns, extinctions, and evolutionary genetic and plasticity changes. New concerns have been raised about the ability of the earth's biodiversity of plants and animals to maintain a viable foothold on the planet if temperatures continue to rise. (See ref. 21 for an alternative point of view). In a recent review on global warming, during the last three decades in wild cereals, the progenitors of cultivated wheat and barley showed earliness in flowering time and in genetic changes (22) and global decline in cultivars’ crops (19). Rapid range shifts of species are associated with high levels of climate warming, shifting to higher elevations at a median rate of 11.0 m per decade, and to higher latitudes at a median rate of 16.9 km per decade, two and three times faster than previously reported (20). Some of the conflicting views on the effects of climate change on biodiversity relate to the fact that the organisms discussed are globally and ecologically spread and, furthermore, do not encompass all life forms at one site. Here I describe a very coherent microscale divergent evolutionary-ecological system dubbed “Evolution Canyon,” which may provide an ideal monitoring system to examine the effects of global warming across life from bacteria to mammals.

Evolution Canyon Model

The Evolution Canyon (EC), the subject of a long-term research program in Israel, started in 1991 at EC I (Lower Nahal Oren, Mount Carmel) and continued in three additional Evolution Canyons [EC II (Lower Nahal Keziv, Western Upper Galilee), EC III (at Nahal Shaharut, southern Negev Desert), and EC IV (Mezar, southern Golan Heights)] (Fig. 1). The more than 200 published studies on all ECs appear in Nevo's Evolution Canyon list at http://evolution.haifa.ac.il and are reviewed by Nevo (23–28).

Fig. 1.

The four “Evolution Canyons” in Israel (EC I–IV). Note the interslope divergence in vegetation between the opposite slopes, even in EC III in the Negev Desert. Detailed plant formations are as follows. EC I: The “African” slope (AS), or South-Facing Slope (SFS), displays a savanna-like park-forest of Carob trees, Ceratonia siliqua- and the bush Lentisk, Pistacia lentiscus, associated with the African grasses Hyparrhenia hirta, Andropogon distachyos, and Penissetum ciliare. The “European” slope (ES), or North-Facing-Slope (NFS), is covered by a dense maquis (brushwood) forest of live-oak, Quercus calliprinos-Pistacia palaestina plant association, including some wild olives Olea europea. EC II: The AS=SFS is as in EC I with the African grasses Hyparrenia hirta and Penisetum ciliare. The ES=NFS is covered with homogeneous forest of Acer obtusifolium-Laurus nobilis. EC III: the SFS is covered with cyanobacteria. The NFS is covered with lichens. The creek vegetation includes trees of Tamarix sp. and bushes of Retama raetam. EC IV: The ES=NFS is covered by the oak Quercus ithaburensis. The AS=SFS is covered by the oak Quercus ithaburensis. The AS=SFS, after long agricultural usage is now dominated by Carthamus tenuis; a few Ziziphus spina-christi trees represent the native savannoid tropical plant community. The substrate of both slopes is volcanic Pleistocene basalt. (Reproduced from ref. 27, figure 2.)

The EC microsite model is optimal to monitor climatic change, primarily global warming. The opposite slopes of the ECs display dramatic biotic contrasts abutting tropical and temperate slopes (Fig. 1). Higher solar radiation (up to 800% more) on the African (AS) south-facing slope (SFS) causes its tropical microclimate (Fig. 2). The AS displays higher solar radiation, temperature, drought, spatiotemporal heterogeneity and fluctuation, and xeric savannoid biota compared with the European (ES) north-facing slope (NFS). The terms “European” and “African” slopes refer to the northern ECs, not to the desert (EC III). The ES = NFS is temperate, cooler, mesic, and forested with maquis live-oak brushwood. The AS is, on average, only 200 m from the ES in the northern ECs. Preliminary microclimatic results at EC I at Lower Nahal Oren, Mount Carmel, show higher illuminance, temperature, and drought on the AS than on the ES (29). Relative humidity, except under the high summer sun, was 1–7% higher on the ES. This dramatic microclimatic divergence causes the drastic interslope biodiversity across life involving bacteria, fungi, plants, and animals. Consequently, local savannoid-forested biodiversity divergence across a few hundred meters displays globally divergent patterns (23). In general, the SFS in canyons north of the equator receive higher solar radiation than NFS. This greater solar radiation acts through soil, air moisture, and temperature on plants and animals (30, 31). Thus, canyons with contrasting SFS and NFS slopes, such as in EC, are excellent natural models for testing climatic change predictions.

Fig. 2.

The EC model. (A) Schematic diagram. (B) Cross section view of EC I, Lower Nahal Oren, Mount Carmel. (C) Air view of EC I. Note the plant formation on opposite slopes. The green, lush, European, temperate, cool-mesic NFS sharply contrasts with the open park forest of warm-xeric, tropical, “African-Asian” savanna on the SFS. In each EC seven sampling stations are designated: three on the SFS (nos. 1–3), one at the valley bottom (no. 4) and three on the NFS (nos. 5–7). (Reproduced from figure 1 in ref. 45.)

In diverse groups of organisms across phylogeny, the tropical Asian-African SFS harbors African and Asian xeric tropical biota. The tropical AS is richer, on average, in terrestrial species than the temperate ES, which is richer in aquatic-dependent taxa (23), as is true globally. In 9 of 14 (64%) model organisms across life, genetic polymorphism of proteins (allozymes) and DNA markers displayed higher frequencies on the AS. Similarly, some model organisms displayed higher mutation frequencies, gene conversion, recombination, DNA repair, genome size, small sequence repeats, SNPs, retrotransposons, transposons, candidate gene diversity, and genome-wide gene expression and regulation on the more drought-stressful AS (27). Besides adaptive divergence, interslope divergence also involves incipient sympatric speciation across life from bacteria to mammals, representing the “Israeli Galapagos” where new incipient species originate on the opposite xeric-tropical and mesic-temperate slopes. Microclimatic selection overrides gene flow and drift (28), and drives both interslope adaptive divergence and incipient sympatric ecological speciation at a microscale.

Besides highlighting many mysteries of evolutionary biology, such as the influence of stress on evolution (33), the EC model also seems optimal for monitoring global warming. The following predictions could be advanced, depending on different species: (i) Increasing global temperatures are expected to lead to significant range shifts from the AS to ES and in the elevation from the upper to the lower station on both slopes. (ii) Similarly, higher migration is expected from the tropical AS to the temperate ES, and from upper to lower stations. (iii) Significant earliness of flowering time was found primarily on the AS. Extinction of species on both slopes, but primarily on the AS, as was initially observed, will be discussed later. (iv) In addition, phenological changes, species interaction, and pest and disease shifts could be expected. (v) Genetically, higher levels of polymorphisms (appearance of new alleles), improved DNA repair, and increase in mutation frequencies may occur primarily on the AS. (vi) Last, but not least, incipient speciation of new species are expected more on the AS. The predictions of species extinction and interslope migration of species were also shown at EC at a microscale (32). Moreover, because the predictions of global climate change are not the same everywhere on the planet, and sensitivity to global warming varies in different species, sampling of ECs throughout the world could provide a better picture of what is happening worldwide. Generalizing this approach leads to a greater world diversity of ECs. The Israeli EC already inspired EC studies elsewhere in the world (Shmuel Raz of the Institute of Evolution at the University of Haifa in collaboration with Ben De Bivort of Harvard University to initiate an EC study in Idaho).

The following overview highlights adaptive patterns to the microclimatic stresses in diverse organisms on the opposite slopes, including higher illuminance, temperature, and drought on the AS and light deprivation in the maquis forest on the ES. Differences between samples of most species analyzed in two EC slopes were grown in a common environment indicating that phenotypic changes have a genetic basis. Increasing global temperatures are expected to drive migration from the AS to ES and the extinction of European taxa on the AS and ES.

Results and Discussion

Adaptations to Solar Radiation and DNA Repair Efficiency.

Natural populations of most organisms are constantly exposed to harsh environmental factors affecting their growth. UV radiation is one of the most important abiotic stresses influencing organisms in nature. In the EC project we highlighted the adaptive response to DNA-damaging agents of UV in natural populations of yeast, soil fungi, wild barley, and Drosophila melanogaster, model organisms studied on the opposite slopes at EC and exposed to a much higher UV radiation on the tropical AS. In the yeast Saccharomyces cerevisiae we studied the phenotypic response of populations to UVA and UVC radiations and to methyl methansulfonate to evaluate the interslope effect on the strain's ability to withstand DNA-damaging agents (34). We exposed our strains to the different DNA-damaging agents and measured survival by counting colony forming units. The AS strains were more resilient to both UVA and methyl methansulfonate than were strains from the ES (Fig. S1). These results suggest that the AS strains are more adapted to higher solar radiation than the ES strains. Remarkably, the tetraploid strains were more tolerant to all DNA-damaging agents than their neighboring diploid strains, suggesting that higher ploidy might be an evolutionary adaptation to high solar radiation in yeast, as is true in angiosperms (35). Future observations are expected to find increased resilience to UVA in AS strains than in ES strains.

DNA repair efficiency as an adaptive trait against solar radiation has been also demonstrated locally at EC I in D. melanogaster (36), and regionally across Israel in wild barley, Hordeum spontaneum (37). The repair efficiency of four thermotolerant and four thermosensitive isofemales lines of D. melanogaster from EC I in Mount Carmel was tested using 2-acetylaminofluorene as the mutagen (36). Thermotolerant isofemale lines showed high DNA repair efficiency at both high and room temperatures. In contrast, thermosensitive isofemale lines were subdivided into high repair efficiency lines at high temperature and inferior thermosensitive lines that showed low DNA repair efficiency at both temperatures. The results suggest the relationship between DNA repair efficiency and thermotolerance with thermotolerant lines tended to repair DNA more efficiently than thermosensitive lines. On a regional scale across Israel, in wild barley H. spontaneum, it was shown that climatically stress-adapted genotypes displayed DNA repair efficiency more significantly (37). Additional evidence is required in more model organisms to substantiate the link between stress tolerance and DNA repair efficiency, as indicated in these initial experiments and, most importantly, to unfold the involved mechanism of DNA repair. Future observations at the AS are expected to show higher DNA repair in Drosophila species and in wild barley, as well as in additional species that could be surveyed for DNA repair.

Melanism.

The adaptive melanin response of the soil fungus Aspergillus niger to UV radiation was clearly demonstrated in EC I (38). Mean conidial melanin concentration of 80 strains was threefold higher on the sunny AS than on the shady ES (Fig. S2), and the former resisted UVA radiation better than the latter. Clearly, melanin in A. niger is an adaptive trait against UVR generated by natural selection. Remarkably, we also showed significant interslope differential growth rates in A. niger at EC I, where the growth rate was ES > AS > Dead Sea (39). On a regional scale we compared the local adaptive patterns of soil mycobiota revealed in the four ECs in Israel (40). Melanized species overwhelmingly dominated the mycobiota of the southern Negev desert EC III at Saharut (Fig. S3A). Melanin-containing fungi also prevailed in the SFS's sunny localities of EC I and EC II in northern Mount Carmel and western Upper Galilee, respectively. Our mycological studies in the four ECs clearly demonstrate spatially (sunny SFS and sunny niches on ES) and seasonally (in summer) higher levels of melanized soil fungi species. Open south-exposed “African” environments of the northern ECs with a moderate level of microclimatic stress supported abundant development of melanin-containing species with small one-celled conidia (Fig. S3B).

Remarkably, located only 50–150 m apart, mild north-exposed European forest environments selected fast-reproducing Penicillium species as dominants. In contrast to the relatively constant and stable microfungal communities of the north-facing ES, those of the AS were subjected to remarkable spatiotemporal changes. Thus, soil microfungal community structure is a sensitive bioindicator of spatiotemporally and ecologically divergent changing conditions at both local and extreme differences on a regional scale (Fig. S3A). Most remarkably, melanization in fungi is an adaptive response to radiation (41). Melanin is highly advantageous for fungi against various environmental stresses of harmful UV and ionizing radiation. Melanin can absorb all types of electromagnetic radiation; hence, it can transform energy and shield the organism. This ability is true for fungi and other melanized organisms inhabiting highly radiated environments across the planet (41). An increased proportion of melanic species of soil fungi is expected on the AS because of ongoing global warming. Intriguingly, the spiny mice Acomys cahirinus modulate the eumelanin-to-pheomelanin ratio to achieve cryptic coloration on the brighter AS (42).

Thermotolerance Adaptations.

The higher solar radiation on the AS slope leads to higher mean daily daytime temperatures and temperature ranges on the AS (29). Top-soil temperature may be 10 °C higher on the AS than on the ES during summer. These higher temperatures lead to higher thermotolerance of the AS populations compared with ES populations, as was shown in the soil bacterium Bacillus simplex (43–45) and the fruit fly D. melanogaster (46). In B. simplex, among 131 strains studied, African strains grew better than European strains at a stressful high temperature (43.25 °C) (Fig. S4). The results suggest that adaptation to hotter and more stressful environments on the AS=SFS slope is ongoing (Fig. S4; see also discussion in ref. 45). Likewise, in wild barley H. spontaneum, dormancy was significantly deeper on the xeric AS than in the mesic ES, as is true across Israel (47, 48).

The results of D. melanogaster consistently resembled other studies: an inverse relationship between survival and heat-shock temperature, male-female differences in thermotolerance, and inducible thermotolerance (46, 49). Females oviposited in the laboratory at temperatures following their origin at EC I (49). Consistently, for all years of collection, AS = SFS flies exceeded ES = NFS flies in basal and inducible thermotolerance after diverse heat shocks, with and without thermal pretreatment (Fig. S5). Even behavioral genes related to sexual behavior and circadian rhythm, such as period, diverge in D. melanogaster displaying interslope differences in the sequence encoding the (Thr-Gly)_n repeat (exon 5), suggesting evolutionary functional importance (50). Increased levels of thermotolerance and dormancy in bacteria (51, 52) as well as in wild cereals are expected on the AS in the future because of global warming.

Drought-Resistance Adaptations.

Drought is one of the major abiotic stresses that limits plant growth. The higher drought on the AS = SFS selects for diverse drought-resistant adaptive complexes. In an area of 7,000 m² we recorded 320 vascular plants species in 217 genera and 59 families (53). Plant cover was dramatically lower on the AS (35%) vs. 150% (including all plant layers) on the ES. The two slopes shared only 31–48% of species. Most species are from the Mediterranean territory on both slopes, but the Saharo-Arabian elements are distributed primarily on the xeric AS = SFS, and Mediterranean and Euro-Siberian elements are mainly distributed on the ES = NFS, thus locally reflecting the regional vegetation type across Israel. The vegetation displays dramatic interslope differences between the hot-xeric Mediterranean savannoid open plant formation on the AS compared with the cooler, mesic dense maquis forest on the ES (Fig. 1). The most extreme difference between the slopes was the predominance of trees and shrubs (two- to eightfold) on the mesic and cooler ES = NFS and the distinct predominance of short-lasting annuals on the xeric and warmer AS = SFS (53).

Intraspecifically, the leaves are small and xeric on the AS displaying drought-resistant adaptation and large and mesic on the ES (54) (Figs. S6 and S7). Even woody plants respond drastically to the microclimatic stresses on opposite slopes of the EC I (54, 55). Seven structural and morphological characteristics of leaves from three woody species (Olea europaea, Ceratonia siliqua, and Pistacia lentiscus) show overall parallel and species-specific leaf xeromorphic interslope microclimatic adaptations (Fig. S6). All leaves of all three species from the AS = SFS were smaller than those from the ES = NFS. Leaves of O. europaea and C. siliqua on the AS were significantly thicker than those on the ES because of increased thickness of the two photosynthetic parenchyma layers, the palisade and spongy layers. A similar significantly increased thickness of the spongy layer was found in leaves of P. lentiscus. The results clearly unfold drought-resistance adaptive complexes on the more arid AS and shade resistance adaptive complexes on the ES caused in woody plants as in annuals (see below) by natural climatic selection (Fig. S6). Xeromorphic characteristics are expected to increase in the future with global warming.

Remarkably, we have shown bigger genome size on the stressful AS in three of four species at EC I; carob tree, C. siliqua (56); annual legume Lotus peregrinus (57), the beetle Oryzaephilus surinamensis (58), with the opposite trend in Cyclamen persicum (59). Similarly, we have shown in soil fungi interslope differences in mutation, crossing over and gene-conversion frequencies (60, 61), all higher on the more stressful AS. We also demonstrated higher polymorphism on the AS in an inter-HIP1 decamer across the genome (62) and in AFLP (63) of the cyanobacterium Nostoc linckia, and in rDNA polymorphism in wild barley (64). Similarly, long-term microclimatic stress caused rapid and quite recent (∼80,000 y ago) adaptive radiation of the KaiABC clock gene family in N. linckia with polymorphism, primarily at the AS, unfolding positive diversifying, balancing, and purifying selections driving forces of the kai gene family's evolution (65). Finally, we have shown that in B. subtilis at EC III in the southern Negev desert, presumably adaptive mutations in the promoter region of the TPP-riboswitch increasing GC content occur on the xeric SFS, whereas mutations on the opposite NFS increase AT content (66). Last but not least, even noncoding retrotransposons are divided by natural selection into two distinct clusters on the AS and ES, suggesting regulation of drought and light deprivation, respectively (67). Both genome size and GC content are expected to increase differentially in different species with global warming.

Stress and Fluctuating Asymmetry.

Fluctuating asymmetry (FA) is arguably considered an indicator of stress. We studied leaf asymmetry of 12 species of vascular plants growing under contrasting microclimates at EC I (55). Leaves of the trees Quercus calliprinos and Pistacia palaestina were significantly more asymmetric on the microclimatically more fluctuating, drier, and savannoid AS = SFS. Leaves of the shrub Calicotome villosa were significantly more asymmetrical on the microclimatically less variable, shadier, and maquis-like ES = NFS. Differences in FA were negatively correlated with differences in local abundance. Species displayed higher FA on the slope where they were less abundant. The results obtained in this study suggest that the AS of EC is only severely stressful for species on the margins of their adaptive zone. Similarly, the ES is only severely stressful for species on the margins of their different adaptive zones. Changes in leaf size of 11 of 12 plant species studied at EC suggest that the phenotypic modifications are more sensitive to stress than FA (Fig. S7). In contrast, only 3 of 12 species showed significant interslope differences in FA. The FA is expected to increase in plant species, particularly on the AS, with global warming.

Adaptive Complexes Against Shade or Light Deprivation.

We studied the crucifer Ricotia lunaria, distantly related to Arabidopsis thaliana, on the opposite slopes of EC I for AFLP genetic diversity (68) and whole-genome interslope divergence (69). The interslope and intraslope biodiversity differed significantly based on both phenotypic and genotypic divergence. The whole-genome interslope divergence showed up-regulation of drought resistance genes on the AS = SFS and shade resistance and up-regulation of photosynthetic genes on the ES = NFS (69). The method of whole-genome analysis (70) showed the following gene ontology results on the AS = SFS drought-stressful slope: the blue light signaling pathway, circadian rhythm, ethylene-mediated genes, leaf development, protein amino acid phosphorylation, RNA splicing, and transcribed transposon development. In addition, more heat-response genes are activated at the AS = SFS as well as a fivefold increase in flower development (69). These interslope divergence patterns are adaptive and channeled by natural selection.

Signals of Global Warming at EC I: Preliminary Realized Predictions.

The AS harbors African rodent derivatives (A. cahirinus, Mus macedonicus), birds (Pycnonotus barbatus, Nectarinia osea), reptiles (Agama stellio), and landsnails (Sphincterochila cariosa). In contrast, the ES harbors European derivatives, such as rodents (Apodemus mystacinus, Apodemus flavicolis), birds (Carduelis carduelis, Carduelis chloris, Turdus merula, and Troglodytes troglodytes), reptiles (Lacerta laevis), and landsnails (Pomatias olivieri) (23). African and European derivative species may be either totally restricted to a single slope or may predominate on one slope and appear with low frequency on the alternative slope [e.g., A. cahirinus and A. mystacinus in rodents (71), and A. stellio and L. laevis in lizards (72)]. Such differentiation is ideal for genotyping (27) and phenotyping (73) organism comparisons, including fluctuating symmetry (55) and stress (33), but most importantly for the monitor of climatic change, particularly global warming. Furthermore, for example, Lacerta viridis disappeared from the ES, and A. mystacinus disappeared from the AS during our long-term research program that started in 1990 (23).

Interslope migration patterns can also monitor global warming, and expectations were realized in D. melanogster. This species has been one of the major model organisms in the EC I research program. In a series of studies reviewed in Korol et al. (74, 75), Nevo et al. (49), and Rashkovetsky et al. (76), we have shown multiple adaptive interslope divergence and incipient sympatric ecological speciation (all articles listed in Nevo's list of EC, found at http://evolution.haifa.ac.il). By means of the capture-mark-release-recapture method, we studied the migration pattern from AS to ES and vice versa (32). Remarkably, the interslope migration was dramatically asymmetric: 9.5% from the AS to ES and less than 2% from the ES to AS in 2003. These preliminary results need further long-term investigation. However, if verified in several years, in the future they may indicate a strong signal of global warming. These experiments could also extend to other organisms across life, especially those identified to be under stress as reflected in lower population size on the AS.

Conclusions and Prospects.

Israel is undergoing global warming (www.environment.gov.il). The maximum temperature in Israel is expected to rise by 1.8 °C by 2020 compared with the years 1960–1990. The EC is an optimal model to follow evolution in action across life in terms of adaptive interslope divergence determined by sharp ecological microclimatic divergence at a microscale. It is also optimal to unfold incipient sympatric ecological speciation across life from bacteria to mammals (26, 27). Intraspecific adaptations to the xeric tropical AS = SFS display higher resistance to solar radiation tolerance and DNA destruction on the AS, as well as to temperature and drought, including signals of fluctuating asymmetry and possibly larger migration to the cooler ES in highly stressed species, such as D. melanogaster. Extinction and migration patterns, as well as effective gene flow from the AS to ES, presumably signaling the stressful effects of global warming, has already been recorded and could be extended in the future to numerous species across life in an attempt to unfold the effects of climate change, particularly with regard to global warming. The EC model, which parallels global patterns of biodiversity and dynamics at a microscale, could be an ideal site for tracking and could demonstrate that recent biological trends of range shifts match climate-change predictions polewards (6–9, 15, 20, 77) and earliness in flowering and ripening (22). These future studies could highlight the effects of global warming at an actively evolving microsite. Because predictions of climate change vary across the planet, it could be very desirable to study additional Evolution Canyons across the planet to get a more comprehensive picture of the climate change phenomena and verify the global predictions of global warming at microscales.

Materials and Methods

We established seven stations, three on each slope: 1, 2, and 3 at altitudes of 120, 90, and 60 meters, respectively, above sea level (a.s.l.) on the “African” south-facing slope (AS=SFS); one station, no. 4 at the valley bottom, and stations 5, 6, and 7 at altitudes of 60, 90, and 120 m a.s.l. on the “European” north-facing slope. The sampling area amounts to 7000 m². Observations, sampling, field and laboratory experiments and analyses relate to these stations and the aforementioned area surrounding them. We recorded the climatic regimes on the opposite slopes and investigated divergence patterns of phenotypes and genotypes across phylogeny including at “Evolution Canyon” I (in round numbers) 2,500 species : bacteria (100 species), Protozoa (5) , fungi (500), plants (340), invertebrates (1,500), and vertebrates (55). Species diversity was estimated by “species richness.” Genetic diversity was tested in 14 model organisms including allozymes and DNA markers (RAPD, SSR, AFLP, and SNP) and recently whole genome analyses revealing structure, expression, and regulation. The main statistics used involve aparametric tests. The genetic basis of interslope divergence was tested in many species by growing them in the same environment. Detailed materials and methods appear in the individual cited papers.