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Biology subjects

Maclean, I.

Publications and source records attributed to Maclean, I..

3 recordsLinked to original sources

Climate-smart prioritisation of tropical Key Biodiversity Areas for protection in response to widespread temperature novelty.

Key Biodiversity Areas (KBAs) are a cornerstone of 21st century area-based conservation targets. In tropical KBAs, biodiversity is potentially at high risk from climate change, because most species reside within or beneath the canopy, where small increases in temperature can lead to novel climate regimes. We quantify novelty in temperature regimes by modelling hourly temperatures below the forest canopy across tropical KBAs between 1990 and 2019. We find that up to 66% of KBAs with tropical forest are likely to have transitioned to novel temperature regimes. Nevertheless, 34% of KBAs are providing refuge from novelty, 58% of which are not protected. By conducting the first pan-tropical analyses of changes in below-canopy temperatures, we identify KBAs that are acting as climate refugia and should be prioritised as candidates for expansion of the conservation network in response to the post-2020 Global Biodiversity Framework target to conserve 30% of land area by 2030.

ecology↗

Re-drawing Koppen-Geiger classes with microclimate: implications for nature and society

Scientists have long categorized the planets climate using the Koppen-Geiger (KG) classification to understand climate change impacts, biogeographical realms, agricultural suitability, and conservation. However, global KG maps primarily rely on macroclimate data collected by weather stations, which may not represent microclimatic conditions experienced by most life on Earth. Few studies have explored microclimate at broad scales, largely due to data and computational constraints. Here, we predicted KG classes separately from macroclimate and microclimate for over 32 million locations across six continents. Microclimate reclassified 38% of the total area, and microclimate KG classes were both more spatially variable, and encompassed a broader range of latitudes, relative to macroclimate KG classes. By redrawing the lines of climate classes, our study prompts a reevaluation of the importance of meteorological drivers of ecology across scales, shedding light on how natural, agricultural, and social systems experience and respond to global change.

ecology↗

Climate-driven variation in biotic interactions provides a narrow and variable window of opportunity for an insect herbivore at its ecological margin

Climate-driven geographic range shifts have been associated with transitions between dietary specialism and generalism at range margins. The mechanisms underpinning these often transient niche breadth modifications are poorly known, but utilisation of novel resources likely depends on phenological synchrony between the consumer and resource. We use a climate-driven range and host shift by the butterfly Aricia agestis to test how climate-driven changes in host phenology and condition affect phenological synchrony, and consider implications for host use. Our data suggest that the perennial plant which was the primary host before range expansion is a more reliable resource than the annual Geraniaceae upon which the butterfly has become specialised in newly colonised parts of its range. In particular, climate-driven phenological variation in the novel host Geranium dissectum generates a narrow and variable window of opportunity for larval productivity in summer. Therefore, although climatic change may allow species to shift hosts and colonise novel environments, specialisation on phenologically-limited hosts may not persist at ecological margins as climate change continues. We highlight the potential role for phenological (a)synchrony in determining lability of consumer-resource associations at range margins, and the importance of considering causes of synchrony in biotic interactions when predicting range shifts.

ecology↗