scholarly journals The evolution of a tropical biodiversity hotspot

Science ◽  
2020 ◽  
Vol 370 (6522) ◽  
pp. 1343-1348 ◽  
Author(s):  
Michael G. Harvey ◽  
Gustavo A. Bravo ◽  
Santiago Claramunt ◽  
Andrés M. Cuervo ◽  
Graham E. Derryberry ◽  
...  
Keyword(s):  
Species Diversity ◽  
Biodiversity Hotspot ◽  
Tropical Biodiversity ◽  
Environmental Extremes ◽  
Speciation Rates ◽  
Gradual Accumulation ◽  
Using Data ◽  
Genomic Regions ◽  
The Tropics ◽  
Over Time

The tropics are the source of most biodiversity yet inadequate sampling obscures answers to fundamental questions about how this diversity evolves. We leveraged samples assembled over decades of fieldwork to study diversification of the largest tropical bird radiation, the suboscine passerines. Our phylogeny, estimated using data from 2389 genomic regions in 1940 individuals of 1287 species, reveals that peak suboscine species diversity in the Neotropics is not associated with high recent speciation rates but rather with the gradual accumulation of species over time. Paradoxically, the highest speciation rates are in lineages from regions with low species diversity, which are generally cold, dry, unstable environments. Our results reveal a model in which species are forming faster in environmental extremes but have accumulated in moderate environments to form tropical biodiversity hotspots.

scholarly journals Determinants of orchid species diversity in Latin America

Lankesteriana ◽  
2016 ◽  
Vol 16 (2) ◽  
Author(s):  
Zuzana Štípková ◽  
Iva Traxmandlová ◽  
Pavel Kindlmann
Keyword(s):  
Latin America ◽  
Species Richness ◽  
Species Diversity ◽  
Protected Areas ◽  
Habitat Diversity ◽  
Orchid Species ◽  
Two Factors ◽  
Using Data ◽  
The Tropics ◽  
Reserve Size

Area and latitude are thought to be the most important determinants of species richness. The relative importance of these two factors was recently tested, using data on orchid species diversity in various countries in the world and it was found that size of the country (or of the protected areas within the country) is a better determinant of species diversity in orchids than latitude. On the other hand, literature data indicate that in many groups species richness is also heavily dependent on habitat diversity as expressed by the range of altitudes in the region considered. Here we analyze the species richness data for various countries in Latin America, using the above-mentioned altitudinal amplitude as a proxy. Habitat diversity played a role in tropical, but not in temperate countries. The reason may indicate that in the temperate countries only few orchid species grow in higher elevations, so an increase of altitudinal range of habitats there does not entail a corresponding increase of species richness there. Thus, especially in the tropics, efforts should be directed to preservation of protected areas in all altitudes, rather than to increase of existing reserve size only in areas that are not attractive for human development. 

scholarly journals Herd-Level and Individual Differences in Fecal Lactobacilli Dynamics of Growing Pigs

Animals ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 113
Author(s):  
Emilia König ◽  
Virpi Sali ◽  
Paulina Heponiemi ◽  
Seppo Salminen ◽  
Anna Valros ◽  
...  
Keyword(s):  
Species Diversity ◽  
Growing Pigs ◽  
General Management ◽  
Immune Parameters ◽  
Sampling Points ◽  
Sequencing Technique ◽  
Piglet Serum ◽  
The Difference ◽  
Over Time ◽  
Fecal Sampling

We studied the fecal lactobacilli count and species diversity of growing pigs along with immune parameters associated with intestinal lactobacilli. Thirty pigs categorized as small (S, n = 12) or large (L, n = 18) at birth were followed from birth to slaughter in two commercial herds, H1 and H2. Herds differed in terms of their general management. We determined sow colostrum quality, colostrum intake, piglet serum immunoglobulins, and pig growth. We took individual fecal samples from pigs in the weaning and finishing units. We studied lactobacilli count and identified their diversity with 16S PCR. Total lactobacilli count increased in H1 and decreased in H2 between samplings. Lactobacilli species diversity was higher in H1 in both fecal sampling points, whereas diversity decreased over time in both herds. We identified altogether seven lactobacilli species with a maximum of five (one to five) species in one herd. However, a relatively large proportion of lactobacilli remained unidentified with the used sequencing technique. Small pigs had higher lactobacilli counts in both herds but the difference was significant only in H2 (p = 0.01). Colostrum quality was numerically better in H1 than in H2, where colostrum intake tended to be associated with total lactobacilli count (p = 0.05).

scholarly journals Predicting climate effects on aquatic true bugs in a tropical biodiversity hotspot

2021 ◽  
Vol 25 (2) ◽  
pp. 229-241
Author(s):  
S. Sundar ◽  
Daniel Paiva Silva ◽  
Fabio de Oliveira Roque ◽  
Juliana Simião-Ferreira ◽  
Jani Heino
Keyword(s):  
Biodiversity Hotspot ◽  
Climate Effects ◽  
True Bugs ◽  
Tropical Biodiversity

How Collective-Action Failure Shapes Group Heterogeneity and Engagement in Conventional and Radical Action Over Time

2021 ◽  
pp. 095679762097056
Author(s):  
Morgana Lizzio-Wilson ◽  
Emma F. Thomas ◽  
Winnifred R. Louis ◽  
Brittany Wilcockson ◽  
Catherine E. Amiot ◽  
...  
Keyword(s):  
Social Movements ◽  
Collective Action ◽  
Latent Profile Analysis ◽  
Profile Analysis ◽  
Social Identification ◽  
Future Research ◽  
Group Efficacy ◽  
Before And After ◽  
Using Data ◽  
Over Time

Extensive research has identified factors influencing collective-action participation. However, less is known about how collective-action outcomes (i.e., success and failure) shape engagement in social movements over time. Using data collected before and after the 2017 marriage-equality debate in Australia, we conducted a latent profile analysis that indicated that success unified supporters of change ( n = 420), whereas failure created subgroups among opponents ( n = 419), reflecting four divergent responses: disengagement (resigned acceptors), moderate disengagement and continued investment (moderates), and renewed commitment to the cause using similar strategies (stay-the-course opponents) or new strategies (innovators). Resigned acceptors were least inclined to act following failure, whereas innovators were generally more likely to engage in conventional action and justify using radical action relative to the other profiles. These divergent reactions were predicted by differing baseline levels of social identification, group efficacy, and anger. Collective-action outcomes dynamically shape participation in social movements; this is an important direction for future research.

Social Change and Psychological Change in Rural Mali

2016 ◽  
Vol 52 (7) ◽  
pp. 965-981 ◽  
Author(s):  
Carmi Schooler ◽  
Leslie J Caplan ◽  
Pakuy Pierre Mounkoro ◽  
Chiaka Diakité
Keyword(s):  
Social Change ◽  
Environmental Change ◽  
Environmental Conditions ◽  
Economic Hardship ◽  
Psychological Change ◽  
Self Confidence ◽  
Personality Stability ◽  
Psychological Reaction ◽  
Using Data ◽  
Over Time

We examine the effects of socio-environmental change on personality in Mali in three ways, using data from a longitudinal two-wave (1994, 2004) survey conducted in rural Mali. Firstly, we compare the between-wave personality stability of Anxiety, Self-confidence, Mastery/Fatalism, and Authoritarianism with that in USA, Japan, Poland, and Ukraine. Secondly, we examine socio-economic hardship and political instability in pre-industrial Mali. Thirdly, we examine patterns of psychological reaction to political and social change during the study period. Our findings have implications for comparisons and generalizations across times and cultures about the contribution of socio-environmental conditions to over-time change in personality.

scholarly journals Camp stability predicts patterns of hunter–gatherer cooperation

2016 ◽  
Vol 3 (7) ◽  
pp. 160131 ◽  
Author(s):  
Daniel Smith ◽  
Mark Dyble ◽  
James Thompson ◽  
Katie Major ◽  
Abigail E. Page ◽  
...  
Keyword(s):  
Real World ◽  
Ecological Context ◽  
Hunter Gatherers ◽  
Ecological Conditions ◽  
Resource Transfers ◽  
Experimental Games ◽  
Using Data ◽  
Over Time ◽  
Do So

Humans regularly cooperate with non-kin, which has been theorized to require reciprocity between repeatedly interacting and trusting individuals. However, the role of repeated interactions has not previously been demonstrated in explaining real-world patterns of hunter–gatherer cooperation. Here we explore cooperation among the Agta, a population of Filipino hunter–gatherers, using data from both actual resource transfers and two experimental games across multiple camps. Patterns of cooperation vary greatly between camps and depend on socio-ecological context. Stable camps (with fewer changes in membership over time) were associated with greater reciprocal sharing, indicating that an increased likelihood of future interactions facilitates reciprocity. This is the first study reporting an association between reciprocal cooperation and hunter–gatherer band stability. Under conditions of low camp stability individuals still acquire resources from others, but do so via demand sharing (taking from others), rather than based on reciprocal considerations. Hunter–gatherer cooperation may either be characterized as reciprocity or demand sharing depending on socio-ecological conditions.

scholarly journals Reconciliation ecology and the future of species diversity

Oryx ◽  
2003 ◽  
Vol 37 (2) ◽  
pp. 194-205 ◽  
Author(s):  
Michael L. Rosenzweig
Keyword(s):  
Steady State ◽  
Species Diversity ◽  
Natural Area ◽  
Reconciliation Ecology ◽  
Anthropogenic Habitats ◽  
Extinction Rates ◽  
Broad Array ◽  
Speciation Rates ◽  
Species Area ◽  
Biogeographical Province

Species-area relationships (SPARs) dictate a sea change in the strategies of biodiversity conservation. SPARs exist at three ecological scales: Sample-area SPARs (a larger area within a biogeographical province will tend to include more habitat types, and thus more species, than a smaller one), Archipelagic SPARs (the islands of an archipelago show SPARs that combine the habitat-sampling process with the problem of dispersal to an island), and Interprovincial SPARs (other things being equal, the speciation rates of larger biogeographical provinces are higher and their extinction rates are lower, leading to diversities in proportion to provincial area). SPARs are the products of steady-state dynamics in diversity, and such dynamics appears to have characterized the earth for most of the last 500 million years. As people reduce the area available to wild species, they impose a linear reduction of the earth's species diversity that will follow the largest of these scales, i.e. each 1% reduction of natural area will cost about 1% of steady-state diversity. Reserving small tracts of wild habitat can only delay these reductions. But we can stop most of them by redesigning anthropogenic habitats so that their use is compatible with use by a broad array of other species. That is reconciliation ecology. Many pilot projects, whether intentionally or inadvertently espousing reconciliation ecology, are demonstrating that it can be done.

Global epidemiology of SARS-CoV-2 infection: a systematic review and meta-analysis of standardized population-based seroprevalence studies, Jan 2020-Oct 2021

2021 ◽  
Author(s):  
Isabel Bergeri ◽  
Mairead Whelan ◽  
Harriet Ware ◽  
Lorenzo Subissi ◽  
Anthony Nardone ◽  
...  
Keyword(s):  
Systematic Review ◽  
Meta Analysis ◽  
Grey Literature ◽  
Population Based ◽  
Control Measures ◽  
Middle Income ◽  
Global Epidemiology ◽  
Using Data ◽  
Demographic Subgroups ◽  
Over Time

Background COVID-19 case data underestimates infection and immunity, especially in low- and middle-income countries (LMICs). We meta-analyzed standardized SARS-CoV-2 seroprevalence studies to estimate global seroprevalence. Objectives/Methods We conducted a systematic review and meta-analysis, searching MEDLINE, Embase, Web of Science, preprints, and grey literature for SARS-CoV-2 seroprevalence studies aligned with the WHO UNITY protocol published between 2020-01-01 and 2021-10-29. Eligible studies were extracted and critically appraised in duplicate. We meta-analyzed seroprevalence by country and month, pooling to estimate regional and global seroprevalence over time; compared seroprevalence from infection to confirmed cases to estimate under-ascertainment; meta-analyzed differences in seroprevalence between demographic subgroups; and identified national factors associated with seroprevalence using meta-regression. PROSPERO: CRD42020183634. Results We identified 396 full texts reporting 736 distinct seroprevalence studies (41% LMIC), including 355 low/moderate risk of bias studies with national/sub-national scope in further analysis. By April 2021, global SARS-CoV-2 seroprevalence was 26.1%, 95% CI [24.6-27.6%]. Seroprevalence rose steeply in the first half of 2021 due to infection in some regions (e.g., 18.2% to 45.9% in Africa) and vaccination and infection in others (e.g., 11.3% to 57.4% in the Americas high-income countries), but remained low in others (e.g., 0.3% to 1.6% in the Western Pacific). In 2021 Q1, median seroprevalence to case ratios were 1.9:1 in HICs and 61.9:1 in LMICs. Children 0-9 years and adults 60+ were at lower risk of seropositivity than adults 20-29. In a multivariate model using data pre-vaccination, more stringent public health and social measures were associated with lower seroprevalence. Conclusions Global seroprevalence has risen considerably over time and with regional variation, however much of the global population remains susceptible to SARS-CoV-2 infection. True infections far exceed reported COVID-19 cases. Standardized seroprevalence studies are essential to inform COVID-19 control measures, particularly in resource-limited regions.

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