The latitudinal gradient in hand-wing-index: global patterns and predictors of wing morphology in birds

AbstractAn organism’s ability to disperse influences many fundamental processes in ecology. However, standardised estimates of dispersal ability are rarely available, and thus the patterns and drivers of broad-scale variation in dispersal ability remain unclear. Here we present a global dataset of avian hand-wing index (HWI), an estimate of wingtip pointedness widely adopted as a proxy for flight efficiency and dispersal in birds. We show that HWI is correlated with geography and ecology across 10,391 (>99 %) bird species, increasing at higher latitudes and in migratory and/or non-territorial species. After controlling for these effects, the strongest predictor of HWI is temperature variability (i.e. seasonality), with secondary effects of diet and habitat type. Our analyses (1) reveal a prominent latitudinal gradient in HWI shaped by ecological and environmental factors, and (2) provide a global index of avian dispersal ability for wider use in community ecology, macroecology, and macroevolution.Statement of authorshipThe study was conceived by CS and JAT. Data collection was led by JAT, SC, and CS, with contributions from CS, MNC, NA, SEIJ, CV, HEAM, TPB, and SC. CS performed the analyses. CS and JAT wrote the manuscript and all authors revised the text.

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Distribution of saltmarsh plant communities associated with environmental factors along a latitudinal gradient on the south-west Atlantic coast

Journal of Biogeography ◽

10.1111/j.1365-2699.2006.01461.x ◽

2006 ◽

Vol 33 (5) ◽

pp. 888-900 ◽

Cited By ~ 208

Author(s):

J. P. Isacch ◽

C. S. B. Costa ◽

L. Rodriguez-Gallego ◽

D. Conde ◽

M. Escapa ◽

...

Keyword(s):

Environmental Factors ◽

Plant Communities ◽

Latitudinal Gradient ◽

Atlantic Coast ◽

The South ◽

South West

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MS prevalence in New Zealand, an ethnically and latitudinally diverse country

Multiple Sclerosis Journal ◽

10.1177/1352458510379614 ◽

2010 ◽

Vol 16 (12) ◽

pp. 1422-1431 ◽

Cited By ~ 54

Author(s):

Bruce V Taylor ◽

John F Pearson ◽

Glynnis Clarke ◽

Deborah F Mason ◽

David A Abernethy ◽

...

Keyword(s):

New Zealand ◽

Environmental Factors ◽

Latitudinal Gradient ◽

Population Level ◽

Cross Sectional Study ◽

European Population ◽

Multiple Sources ◽

Cross Sectional ◽

The North ◽

Mcdonald Criteria

Background: The prevalence of multiple sclerosis (MS) is not uniform, with a latitudinal gradient of prevalence present in most studies. Understanding the drivers of this gradient may allow a better understanding of the environmental factors involved in MS pathogenesis. Method: The New Zealand national MS prevalence study (NZMSPS) is a cross-sectional study of people with definite MS (DMS) (McDonald criteria 2005) resident in New Zealand on census night, 7 March 2006, utilizing multiple sources of notification. Capture—recapture analysis (CRA) was used to estimate missing cases. Results: Of 2917 people with DMS identified, the crude prevalence was 72.4 per 100,000 population, and 73.1 per 100,000 when age-standardized to the European population. CRA estimated that 96.7% of cases were identified. A latitudinal gradient was seen with MS prevalence increasing three-fold from the North (35°S) to the South (48°S). The gradient was non-uniform; females with relapsing—remitting/secondary-progressive (RRMS/SPMS) disease have a gradient 11 times greater than males with primary-progressive MS ( p < 1 × 10-7). DMS was significantly less common among those of Māori ethnicity. Conclusions: This study confirms the presence of a robust latitudinal gradient of MS prevalence in New Zealand. This gradient is largely driven by European females with the RRMS/SPMS phenotype. These results indicate that the environmental factors that underlie the latitudinal gradient act differentially by gender, ethnicity and MS phenotype. A better understanding of these factors may allow more targeted MS therapies aimed at modifiable environmental triggers at the population level.

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The Occurence of Ecological Traps in Bird Populations: Is our Knowledge Sufficient? A Review

Journal of Landscape Ecology ◽

10.2478/v10285-012-0058-4 ◽

2012 ◽

Vol 5 (3) ◽

pp. 36-56 ◽

Cited By ~ 4

Author(s):

Petr Suvorov ◽

Jana Svobodová

Keyword(s):

Exotic Species ◽

Species Conservation ◽

Habitat Type ◽

Bird Species ◽

Ecological Trap ◽

Native Communities ◽

Bird Populations ◽

Suburban Areas ◽

Arable Fields ◽

Insufficient Time

ABSTRACT Anthropogenic changes in a landscape create new cues for birds, which must permanently adapt to these. If landscape changes occur too quickly, individuals have insufficient time to develop adequate reactions. They may, therefore, preferentially nest in low-quality habitats, which can lead to diminished nesting success and to reduction of their population size. This is usually termed the ecological trap hypothesis. We reviewed 38 studies investigating this phenomenon and analysed whether relationships exist between ecological trap occurrence and geographical region, habitat type, and/or life strategies of bird species. Ecological traps were most often associated with the presence of exotic species. Exotic species can modify environmental conditions in ways to which native communities are not adapted. They have been mainly detected in open habitats. Such open habitats as arable fields and meadows are under greater human pressure, and rapid changes probably occur there more frequently. Although more studies from North America were investigated, the hypothesis was supported more frequently in European studies. This is possibly due to higher human population density and, hence, more frequent habitat changes. Our results show that an ecological trap is not likely associated with migration. Ground nests suffered fewer consequences of such traps than did other nest types. Although the implications of the ecological trap hypothesis in species conservation are undisputable, a more detailed approach is still needed. For instance, some habitat types, such as suburban areas, have been neglected in the context of ecological traps, as has been the phenomenon’s appearance in pristine habitats.

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Scale-dependent environmental filtering of ground-dwelling predators in winter wheat and adjacent set-aside areas in Hungary

Journal of Insect Conservation ◽

10.1007/s10841-020-00249-9 ◽

2020 ◽

Vol 24 (5) ◽

pp. 751-763

Author(s):

Jana Růžičková ◽

Ferenc Kádár ◽

Ottó Szalkovszki ◽

Anikó Kovács-Hostyánszki ◽

András Báldi ◽

...

Keyword(s):

Winter Wheat ◽

Natural Enemies ◽

Spatial Scales ◽

Habitat Type ◽

Environmental Filtering ◽

Landscape Scale ◽

Dispersal Ability ◽

Field Scale ◽

Wheat Field ◽

Activity Density

Abstract Agricultural intensification may act as an environmental filter shaping invertebrate assemblages at multiple spatial scales. However, it is not fully understood which scale is the most influential. Therefore, we utilized a hierarchical approach to examine the effect of local management (inorganic fertilization and soil properties; within-field scale), habitat type (winter wheat field and set-aside field; between-field scale) and landscape complexity (landscape scale) on assemblage structure and functional diversity of two important groups of natural enemies, carabids and spiders, in a cultivated lowland landscape in Hungary. Environmental filtering affected natural enemies at different spatial scales; likely as a result of enemies’ different dispersal ability and sensitivity to fertilizer use. Carabids were strongly affected at the within-field scale: positively by soil pH, negatively by soil organic matter and fertilization. At the between-field scale, carabids had higher activity density in the set-aside fields than in the winter wheat fields and simple landscapes enhanced carabids diversity, species richness and activity density at the landscape scale. Spiders were more abundant and species-rich in the set-aside fields than in the winter wheat fields. Although highly mobile (macropterous) carabids might disperse to arable crops from greater distances, while spiders possibly depended more on the proximity of set-aside fields, the winter wheat fields (where pest control should be delivered) were utilized mostly by common agrobiont species. Increasing crop heterogeneity within arable fields could be a potential option to increase the diversity of carabids and spiders in the studied region.

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Spatiotemporal Variations in Mercury Bioaccumulation at Fine and Broad Scales for Two Freshwater Sport Fishes

Water ◽

10.3390/w10111625 ◽

2018 ◽

Vol 10 (11) ◽

pp. 1625 ◽

Cited By ~ 2

Author(s):

Shyam Thomas ◽

Stephanie Melles ◽

Satyendra Bhavsar

Keyword(s):

Climate Change ◽

Environmental Factors ◽

Northern Pike ◽

Space Time ◽

Fine Scale ◽

Spatiotemporal Variations ◽

Scale Models ◽

Change Context ◽

Mercury Bioaccumulation ◽

Broad Scale

Bioaccumulation of mercury in sport fish is a complex process that varies in space and time. Both large-scale climatic as well as fine-scale environmental factors are drivers of these space-time variations. In this study, we avail a long-running monitoring program from Ontario, Canada to better understand spatiotemporal variations in fish mercury bioaccumulation at two distinct scales. Focusing on two common large-bodied sport fishes (Walleye and Northern Pike), the data were analyzed at fine- and broad-scales, where fine-scale implies variations in bioaccumulation at waterbody- and year-level and broad-scale captures variations across 3 latitudinal zones (~5° each) and eight time periods (~5-year each). A series of linear mixed-effects models (LMEMs) were employed to capture the spatial, temporal and spatiotemporal variations in mercury bioaccumulation. Fine-scale models were overall better fit than broad-scale models suggesting environmental factors operating at the waterbody-level and annual climatic conditions matter most. Moreover, for both scales, the space time interaction explained most of the variation. The random slopes from the best-fitting broad-scale model were used to define a bioaccumulation index that captures trends within a climate change context. The broad-scale trends suggests of multiple and potentially conflicting climate-driven mechanisms. Interestingly, broad-scale temporal trends showed contrasting bioaccumulation patterns—increasing in Northern Pike and decreasing in Walleye, thus suggesting species-specific ecological differences also matter. Overall, by taking a scale-specific approach, the study highlights the overwhelming influence of fine-scale variations and their interactions on mercury bioaccumulation; while at broad-scale the mercury bioaccumulation trends are summarized within a climate change context.

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Community structure of Neotropical wetland insects in Northern Venezuela. II. Habitat type and environmental factors app:1

Fundamental and Applied Limnology / Archiv für Hydrobiologie ◽

10.1127/archiv-hydrobiol/155/2002/437 ◽

2002 ◽

Vol 155 (3) ◽

pp. 437-453 ◽

Cited By ~ 6

Author(s):

Maria Eugenia Grillet ◽

Pierre Legendre ◽

Daniel Borcard

Keyword(s):

Community Structure ◽

Environmental Factors ◽

Habitat Type

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Latitudinal gradients in intraspecific ecological diversity

Biology Letters ◽

10.1098/rsbl.2013.0778 ◽

2013 ◽

Vol 9 (6) ◽

pp. 20130778 ◽

Cited By ~ 26

Author(s):

Márcio S. Araújo ◽

Raul Costa-Pereira

Keyword(s):

Species Diversity ◽

Latitudinal Gradient ◽

Latitudinal Gradients ◽

Ecological Diversity ◽

Invertebrate Animal ◽

Niche Variation ◽

Wide Range ◽

Global Patterns ◽

Global Biodiversity ◽

New Perspective

The increase in the number of species with decreasing latitude is a striking pattern of global biodiversity. An important feature of studies of this pattern up to now has been the focus on species as the fundamental unit of interest, neglecting potential within-species ecological diversity. Here, we took a new perspective on this topic by measuring the degree to which individuals within populations differ in niche attributes across a latitudinal gradient (range: 54.01° S to 69.12° N). We show that 156 populations of 76 species across a wide range of vertebrate and invertebrate animal taxa contain more ecologically diverse assemblages of individuals towards lower latitudes. Our results add a new level of complexity to our understanding of global patterns of biodiversity and suggest the possibility that niche variation is partly responsible for the latitudinal gradients of species diversity.

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