Reassessing niche partitioning in MacArthur’s warblers: foraging behaviour, morphology and diet differentiation in a phylogenetic context

Biology Letters, Год журнала: 2025, Номер 21(4)

Опубликована: Апрель 1, 2025

Owing in large part to Robert MacArthur’s classic research, wood warblers the family Parulidae are textbook exemplars of species competition and niche partitioning. Conventional wisdom suggests that subtle differences foraging behaviour principal means by which these nearly morphologically indistinguishable able co-occur avoid extinction. Yet, study was fact quite limited scale, he said little about relevance evolution system. Here, we reassess conclusions across an expanded set syntopic warbler a forest northern New York. We combine morphometrics, quantitative data faecal metabarcoding—a direct measure diet—to partitioning evolutionary framework. find close relationships between morphology behaviour, but connection ecomorphology 2237 invertebrate taxa detected their diets. Instead, diet remains phylogenetically conserved—closely related eat similar suites invertebrates, regardless where they forage. Finally, present evidence not only partition space day also has shaped behaviours over time.

Язык: Английский

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Multiple factors shape the elevational distribution patterns of mountain ungulates in Southwest China

Global Ecology and Conservation, Год журнала: 2025, Номер unknown, С. e03592 - e03592

Опубликована: Апрель 1, 2025

Язык: Английский

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Mechanisms of individual variation in large herbivore diets: Roles of spatial heterogeneity and state‐dependent foraging

Ecology, Год журнала: 2022, Номер 104(2)

Опубликована: Ноя. 23, 2022

Abstract Many populations of consumers consist relatively specialized individuals that eat only a subset the foods consumed by population at large. Although ecological significance individual‐level diet variation is recognized, such difficult to document, and its underlying mechanisms are poorly understood. Optimal foraging theory provides useful framework for predicting how might select different diets, positing animals balance “opportunity cost” stopping an available food item against cost searching something more nutritious; composition should be contingent on distribution food, individual foragers selective when they have greater energy reserves invest in high‐quality foods. We tested these predicted niche differentiation quantifying environmental (resource heterogeneity) organismal (nutritional condition) determinants widespread browsing antelope (bushbuck, Tragelaphus sylvaticus ) African floodplain‐savanna ecosystem. quantified individuals' realized dietary niches (taxonomic richness composition) using DNA metabarcoding fecal samples collected repeatedly from 15 GPS‐collared (range 6–14 per individual, median 12). Bushbuck diets were structured spatial heterogeneity constrained condition. observed significant partitioning plants bushbuck both within between two adjacent habitat types (floodplain woodland). Individuals with home ranges closer together and/or had similar vegetation structure (measured LiDAR) ate supporting prediction heterogeneous resource promotes differentiation. good nutritional condition significantly narrower (fewer plant taxa), searched their intensively (intensity‐of‐use index), higher‐quality (percent digestible protein) than those poor condition, endogenous because can time nutritious Our results support predictions optimal about energetic basis provide potentially generalizable understanding width governed animal behavior physiology landscapes.

Язык: Английский

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Micro-photoautotroph predation as a driver for trophic niche specialization in 12 syntopic Indo-Pacific parrotfish species

Biological Journal of the Linnean Society, Год журнала: 2023, Номер 139(2), С. 91 - 114

Опубликована: Апрель 12, 2023

Abstract Parrotfish are key agents of bioerosion and sediment production in coral reef ecosystems; however, their dietary targets therefore potential sources variation carbonate cycling lack resolution. Here we address this knowledge shortfall our current understanding parrotfish diets by testing the concept that protein-rich micro-photoautotrophs target prey for many Scarinine parrotfishes. We focus at fine spatial scales on feeding substrata 12 syntopic Indo-Pacific species mid-shelf sites around Lizard Island, Great Barrier Reef, Australia. followed individual snorkel until biting was observed, then extracted a core each bite. The surface bite scraped to ~1 mm quantitative microscopic analysis (up 630 × magnification) 16S 18S rRNA metabarcoding. most dominant photoautotrophic group terms cover filamentous cyanobacteria, crustose coralline algae. Epiphytic, epilithic, endophytic endolithic cyanobacteria were consistent biota. Although density cores largely among species, data metabarcoding revealed distinct differences between taxonomic composition Our provide further evidence these partition resources.

Язык: Английский

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Rethinking livestock encroachment at a protected area boundary

Proceedings of the National Academy of Sciences, Год журнала: 2024, Номер 121(38)

Опубликована: Сен. 9, 2024

The presence of livestock inside protected areas, or “livestock encroachment,” is a global conservation concern because broadly thought to negatively affect wildlife. Maasai Mara National Reserve (MMNR), Kenya, exemplifies this tension as believed have resulted in the declining wildlife populations, contributing strict and sometimes violent exclusion measures targeting pastoralists. However, research embedded real-world setting that draws insights from social–ecological contexts lacking. In study, we conducted 19 mo ecological monitoring covering 60 sites MMNR found cattle reserve did not significantly impact most co-occurring wild herbivores at current intensity. Using Hierarchical Modeling Species Communities Gaussian copula graphic models, showed had no direct associations—neither negative nor positive—with nearly all despite frequently sharing same space. Moreover, detect resource degradation correlated with near boundary. Given colonial legacy land use history Mara, entering becomes only viable option for many herders. These results corroborate emerging perspective impacts extensively herded on might be more nuanced than previously thought. To effectively balance needs people, livestock, wildlife, rigid need reassessed holistically consider herbivore ecology, local history, modern politics area management.

Язык: Английский

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