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In animal-pollinated flowers, the pollinators cannot detect the presence of nectar before entering flowers, and therefore flowers may cheat by not producing nectar. An earlier model suggested that a mixed strategy of producing nectarful and nectarless flowers would be evolutionarily stable. Here we compare nectarless flowers as a cheating strategy with three competing hypotheses namely "visit-more-flowers", "cross-pollination enhancement" and "better contact". We collected field data on 28 species of plants to test some of the differential predictions of the hypotheses. Nectarless flowers were detected in 24 out of 28 plant species. Correlations of percent nectarless flowers with floral and ecological variables support the cheater flower hypothesis. We further model the cost-benefits of cheating and show that an evolutionary stable ratio of nectarless to nectarful flowers can be reached. The equilibrium ratio is mainly decided by factors associated with pollinator density and pollinator learning.

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The importance of patch quality for amphibians is frequently overlooked in distribution models. Here we demonstrate that it is highly important for the persistence of endemic and endangered amphibians found in the threatened and fragile ecosystems that are the rocky plateaus in Western Maharashtra, India. These plateaus are ferricretes of laterite and characterise the northern section of the Western Ghats/Sri Lanka Biodiversity Hotspot, the eighth most important global hotspot and one of the three most threatened by population growth. We present statistically supported habitat associations for endangered and data-deficient Indian amphibians, demonstrating significant relationships between individual species and their microhabitats. Data were collected during early monsoon across two seasons. Twenty-one amphibian taxa were identified from 14 lateritic plateaus between 67 and 1179m above sea level. Twelve of the study taxa had significant associations with microhabitats using a stepwise analysis of the AICc subroutine (distLM, Primer-e, v7). Generalist taxa were associated with increased numbers of microhabitat types. Non-significant associations are reported for the remaining 9 taxa. Microhabitat distribution was spatially structured and driven by climate and human activity. Woody plants were associated with 44% of high-elevation taxa. Of the 8 low-elevation taxa 63% related to water bodies and 60% of those were associated with pools. Rock size and abundance were important for 33% of high elevation specialists. Three of the 4 caecilians were associated with rocks in addition to soil and stream presence. We conclude the plateaus are individualistic patches whose habitat quality is defined by their microhabitats within climatic zones.

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