Publications by authors named "Jose da Silva Guimaraes"

Amazonian forests are extraordinarily diverse, but the estimated species richness is very much debated. Here, we apply an ensemble of parametric estimators and a novel technique that includes conspecific spatial aggregation to an extended database of forest plots with up-to-date taxonomy. We show that the species abundance distribution of Amazonia is best approximated by a logseries with aggregated individuals, where aggregation increases with rarity.

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Article Synopsis
  • Species distribution models (SDMs), like MaxEnt, often rely on natural history collections (NHCs) for data, but these collections can be spatially biased, affecting model accuracy.
  • A study tested the relationship between NHC distribution and a spatial abundance model (IDW) for Amazonian tree species, finding a weak positive correlation for most species analyzed.
  • The proposed new pipeline effectively reduced NHC inconsistencies and trimmed unnecessary data, offering a more conservative estimate of species occupancy, which is vital for large biodiversity assessments and conservation status evaluations.
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Estimates of extinction risk for Amazonian plant and animal species are rare and not often incorporated into land-use policy and conservation planning. We overlay spatial distribution models with historical and projected deforestation to show that at least 36% and up to 57% of all Amazonian tree species are likely to qualify as globally threatened under International Union for Conservation of Nature (IUCN) Red List criteria. If confirmed, these results would increase the number of threatened plant species on Earth by 22%.

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The aim of this study was to evaluate a nasal vaccine using antigens derived from sporozoites of Eimeria tenella incorporated into Iscom to protect broiler chicks. Forty-five one-day-old chickens (Cobb), unvaccinated against coccidiosis, were used in this experiment. The birds were maintained in separated battery cages and divided into three groups: G1 (n=15), G2 (n=15), and G3 (n=15).

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