Publications by authors named "Alexander C Lees"

Insects are one of the most diverse taxa and are fundamental to the delivery of many ecosystem services. Despite their global ubiquity and ecological importance, there is little research on temporal variation in insect activity, especially in the tropics where the group is most diverse. Gaps in our knowledge of insects are compounded by a lack of robust methods to monitor their activity at fine timescales.

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Wings with an elongated shape or larger surface area are associated with increased flight efficiency in a wide range of animals from insects to birds. Inter- and intra-specific variation in these attributes of wing shape is determined by a range of factors-including foraging ecology, migration, and climatic seasonality-all of which may drive latitudinal gradients in wing morphology. A separate hypothesis predicts that wing shape should also follow an elevational gradient because air density declines with altitude, altering the aerodynamics of flight and driving the evolution of more efficient wings in high-elevation species to compensate for reduced lift.

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Biodiversity loss is occurring globally with negative impacts on ecosystem function and human well-being. There is a scientific consensus that diverse environmental and anthropogenic factors are altering different components of insect biodiversity, with changes occurring at all levels of biological organisation. Here, we describe how uncertainty around specific trends and the semantics of 'decline' in relation to insect biodiversity have been leveraged by denialist campaigns to manufacture doubt around the insect biodiversity crisis.

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Vagrancy is the occurrence of individuals outside the normal geographic range of their species. These rare and unpredictable events have long been neglected by the scientific community, belying a growing body of evidence that vagrancy can have an important role in eco-evolutionary processes at both population and community scales.

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Biodiversity loss is one of the main challenges of our time, and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space. While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes, vast areas of the tropics remain understudied. In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity, but it remains among the least known forests in America and is often underrepresented in biodiversity databases.

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Understanding the composition of urban wildlife communities is crucial to promote biodiversity, ecosystem function and links between nature and people. Using crowdsourced data from over five million eBird checklists, we examined the influence of urban characteristics on avian richness and function at 8443 sites within and across 137 global cities. Under half of the species from regional pools were recorded in cities, and we found a significant phylogenetic signal for urban tolerance.

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Inner phenomena, such as personal motivations for pursuing sustainability, may be critical levers for improving conservation outcomes. Most conservation research and policies, however, focus on external phenomena (e.g.

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Alexander Lees and Pramana Yuda introduce the songbird trade of Southern and Eastern Asia that is a major threat to regional bird populations.

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Human activities pose a major threat to tropical forest biodiversity and ecosystem services. Although the impacts of deforestation are well studied, multiple land-use and land-cover transitions (LULCTs) occur in tropical landscapes, and we do not know how LULCTs differ in their rates or impacts on key ecosystem components. Here, we quantified the impacts of 18 LULCTs on three ecosystem components (biodiversity, carbon, and soil), based on 18 variables collected from 310 sites in the Brazilian Amazon.

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Vagrant birds are frequently recorded outside of their regular geographic range. A new study documents how vagrancy, in this case in an Asian songbird, can lead to establishment of a new migration route.

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Conservation initiatives overwhelmingly focus on terrestrial biodiversity, and little is known about the freshwater cobenefits of terrestrial conservation actions. We sampled more than 1500 terrestrial and freshwater species in the Amazon and simulated conservation for species from both realms. Prioritizations based on terrestrial species yielded on average just 22% of the freshwater benefits achieved through freshwater-focused conservation.

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Tropical forests and coral reefs host a disproportionately large share of global biodiversity and provide ecosystem functions and services used by millions of people. Yet, ongoing climate change is leading to an increase in frequency and magnitude of extreme climatic events in the tropics, which, in combination with other local human disturbances, is leading to unprecedented negative ecological consequences for tropical forests and coral reefs. Here, we provide an overview of how and where climate extremes are affecting the most biodiverse ecosystems on Earth and summarize how interactions between global, regional and local stressors are affecting tropical forest and coral reef systems through impacts on biodiversity and ecosystem resilience.

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Habitat loss, fragmentation, and degradation have pervasive detrimental effects on tropical forest biodiversity, but the role of the surrounding land use (i.e., matrix) in determining the severity of these impacts remains poorly understood.

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Organismal appearances are shaped by selection from both biotic and abiotic drivers. For example, Gloger's rule describes the pervasive pattern that more pigmented populations are found in more humid areas. However, species may also converge on nearly identical colours and patterns in sympatry, often to avoid predation by mimicking noxious species.

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Article Synopsis
  • Secondary forests (SFs) are increasingly important for carbon storage and biodiversity, regenerating on previously deforested tropical lands.
  • Despite their recovery, SFs do not fully replicate the biodiversity and structure of undisturbed primary forests (UPFs), with an average recovery of 88% species richness after up to 40 years.
  • The study shows that while SFs accumulate carbon and support many species, they cannot replace UPFs, highlighting the need for ongoing conservation efforts in primary forests.
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The tropics contain the overwhelming majority of Earth's biodiversity: their terrestrial, freshwater and marine ecosystems hold more than three-quarters of all species, including almost all shallow-water corals and over 90% of terrestrial birds. However, tropical ecosystems are also subject to pervasive and interacting stressors, such as deforestation, overfishing and climate change, and they are set within a socio-economic context that includes growing pressure from an increasingly globalized world, larger and more affluent tropical populations, and weak governance and response capacities. Concerted local, national and international actions are urgently required to prevent a collapse of tropical biodiversity.

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Vertebrates perform key roles in ecosystem processes via trophic interactions with plants and insects, but the response of these interactions to environmental change is difficult to quantify in complex systems, such as tropical forests. Here, we use the functional trait structure of Amazonian forest bird assemblages to explore the impacts of land-cover change on two ecosystem processes: seed dispersal and insect predation. We show that trait structure in assemblages of frugivorous and insectivorous birds remained stable after primary forests were subjected to logging and fire events, but that further intensification of human land use substantially reduced the functional diversity and dispersion of traits, and resulted in communities that occupied a different region of trait space.

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