Publications by authors named "John M Halley"

Diversification of plant chemical phenotypes is typically associated with spatially and temporally variable plant-insect interactions. Floral scent is often assumed to be the target of pollinator-mediated selection, whereas foliar compounds are considered targets of antagonist-mediated selection. However, floral and vegetative phytochemicals can be biosynthetically linked and may thus evolve as integrated phenotypes.

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Orchids constitute one of the most spectacular radiations of flowering plants. However, their origin, spread across the globe, and hotspots of speciation remain uncertain due to the lack of an up-to-date phylogeographic analysis. We present a new Orchidaceae phylogeny based on combined high-throughput and Sanger sequencing data, covering all five subfamilies, 17/22 tribes, 40/49 subtribes, 285/736 genera, and c.

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Future systems of extreme isolation, including initiatives in space exploration, may require the services of onboard ecosystems. Biosphere 2, which ran between 1991 and 1993, aspired to mimic the earthly ecosystem and assess the ability of humans and other species to survive in a fully enclosed space. In this study, the data for plant species survival in the tropical rainforest sector from the first 2-year mission were studied through the prism of the neutral theory of biodiversity (NTB), which predicts how closed communities develop and how they lose species due to random demographic effects.

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Loss of habitat can take many forms, ranging from the fragmentation of once-continuous habitat to the slow erosion of populations across continents. Usually, the harm leading to biodiversity loss is not immediately obvious: there is an extinction debt. Most modelling research of extinction debt has focussed on relatively rapid losses of habitat with species loss happening in response afterwards.

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Many protected areas worldwide increasingly resemble habitat isolates embedded in human-modified landscapes. However, establishing linkages among protected areas could significantly reduce species-loss rates. Here we present a novel method having broad applicability for assessing enhanced regional connectivity on persistence of mammal diversity.

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In the midst of a persistent pandemic of a probable zoonotic origin, one needs to constantly evaluate the interplay of SARS-CoV-2 (severe acute respiratory syndrome-related coronavirus-2) with animal populations. Animals can get infected from humans, and certain species, including mink and white-tailed deer, exhibit considerable animal-to-animal transmission resulting in potential endemicity, mutation pressure, and possible secondary spillover to humans. We attempt a comprehensive review of the available data on animal species infected by SARS-CoV-2, as presented in the scientific literature and official reports of relevant organizations.

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Numerous orchid species around the world have already been affected by the ongoing climate change, displaying phenological alterations and considerable changes to their distributions. The fly orchid ( L.) is a well-known and distinctive species in Europe, with a broad distribution across the continent.

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The emergence of novel SARS-CoV-2 variants of concern (VOC), in late 2020, with selective transmission advantage and partial immunity escape potential, has been driving further evolution in the pandemic. The timing of mutational evolution and its limits are thus of paramount importance in preparedness planning. Here, we present a model predicting the pattern of epidemic growth including the emergence of variants through mutation.

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Climate change is regarded as one of the most important threats to plants. Already species around the globe are showing considerable latitudinal and altitudinal shifts. Helen's bee orchid (), a Balkan endemic with a distribution center in northwestern Greece, is reported to be expanding east and southwards.

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Inferring species' responses to climate change in the absence of long-term time series data is a challenge, but can be achieved by substituting space for time. For example, thermal elevational gradients represent suitable proxies to study phenological responses to warming. We used butterfly data from two Mediterranean mountain areas to test whether mean dates of appearance of communities and individual species show a delay with increasing altitude, and an accompanying shortening in the duration of flight periods.

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Background: In Epirus, Greece, orchids have been traditionally harvested for the production of salep, a beverage made from their tubers. Over-collection of orchids for salep is believed to be a growing threat to wild species, yet very little research has concentrated on orchid populations in the wild. Here, we studied the impact of salep collection on population demographic parameters and uniformity of distribution patterns of the Elder-flowered orchid, , the most commonly collected orchid in northern Greece.

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We explore how the phyllosphere microbial community responds to a very seasonal environment such as the Mediterranean. For this, we studied the epiphytic bacterial community of a Mediterranean ecosystem in summer and winter, expecting to detect seasonal differences at their maximum. With high-throughput sequencing (HTS), we detected the operational taxonomic units (OTUs) present in the phyllosphere and also in the surrounding air.

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Human activities are exposing organisms not only to direct threats (e.g. habitat loss) but also to indirect environmental pressures such as climate change, which involves not just directional global warming but also increasing climatic variability.

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The Eastern Arc Mountains of Tanzania and the Atlantic Forest of Brazil are two of the most fragmented biodiversity hotspots. Species-area relationships predict that their habitat fragments will experience a substantial loss of species. Most of these extinctions will occur over an extended time, and therefore, reconnecting fragments could prevent species losses and allow locally extinct species to recolonize former habitats.

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Background: The abundant-centre hypothesis (ACH) assumes that a species becomes more abundant at the centre of its range, where the environmental conditions are most favorable. As we move away from this centre, abundance and occupancy decline. Although this is obvious intuitively, efforts to confirm the hypothesis have often failed.

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Predicting biodiversity relaxation following a disturbance is of great importance to conservation biology. Recently-developed models of stochastic community assembly allow us to predict the evolution of communities on the basis of mechanistic processes at the level of individuals. The neutral model of biodiversity, in particular, has provided closed-form solutions for the relaxation of biodiversity in isolated communities (no immigration or speciation).

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Species extinction following habitat loss is well documented. However, these extinctions do not happen immediately. The biodiversity surplus (extinction debt) declines with some delay through the process of relaxation.

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No species lives on earth forever. Knowing when and why species go extinct is crucial for a complete understanding of the consequences of anthropogenic activity, and its impact on ecosystem functioning. Even though soil biota play a key role in maintaining the functioning of ecosystems, the vast majority of existing studies focus on aboveground organisms.

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Naturalists as early as Darwin observed terrestrial basking in green turtles (Chelonia mydas), but the distribution and environmental influences of this behaviour are poorly understood. Here, we examined 6 years of daily basking surveys in Hawaii and compared them with the phenology of local sea surface temperatures (SST). Data and models indicated basking peaks when SST is coolest, and we found this timeline consistent with bone stress markings.

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Very little is known about the impact of climate change on fungi and especially on spore production. Fungal spores can be allergenic, thus being important for human health. The aim of this study was to investigate how climate change influences the responsive ability of fungi by simulating differing environmental regimes.

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The European protected-area network will cease to be efficient for biodiversity conservation, particularly in the Mediterranean region, if species are driven out of protected areas by climate warming. Yet, no empirical evidence of how climate change influences ecological communities in Mediterranean nature reserves really exists. Here, we examine long-term (1998-2011/2012) and short-term (2011-2012) changes in the butterfly fauna of Dadia National Park (Greece) by revisiting 21 and 18 transects in 2011 and 2012 respectively, that were initially surveyed in 1998.

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The species-area relationship (SAR) predicts that smaller areas contain fewer species. This is the basis of the SAR method that has been used to forecast large numbers of species committed to extinction every year due to deforestation. The method has a number of issues that must be handled with care to avoid error.

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A paper by Wearn et al. (Reports, 13 July 2012, p. 228) yields new insights on extinction debt.

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