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1.
Mol phylogenet evol, v. 140, p.106569, nov. 2019
Artículo en Inglés | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-2821

RESUMEN

Phylogenetic niche conservatism (PNC) shapes the distribution of organisms by constraining lineages to parti-cular climatic conditions. Conversely, if areas with similar climates are geographically isolated, diversificationmay also be limited by dispersal. Neotropical xeric habitats provide an ideal system to test the relative roles ofclimate and geography on diversification, as they occur in disjunct areas with similar biotas. Sicariinae sandspiders are intimately associated with these xeric environments, particularly seasonally dry tropical forests(SDTFs) and subtropical deserts/scrublands in Africa (Hexophthalma) and the Neotropics (Sicarius). We explorethe role of PNC, geography and biome shifts in their evolution and timing of diversification. We estimated atime-calibrated, total-evidence phylogeny of Sicariinae, and used published distribution records to estimateclimatic niche and biome occupancy. Topologies were used for estimating ancestral niches and biome shifts. Weused variation partitioning methods to test the relative importance of climate and spatially autocorrelatedfactors in explaining the spatial variation in phylogenetic structure ofSicariusacross the Neotropics. NeotropicalSicariusare ancient and split from their African sister-group around 90 (57–131) million years ago. Most spe-ciation events took place in the Miocene. Sicariinae records can be separated in two groups corresponding totemperate/dry and tropical/seasonally dry climates. The ancestral climatic niche of Sicariinae are temperate/dryareas, with 2–3 shifts to tropical/seasonally dry areas inSicarius. Similarly, ancestral biomes occupied by thegroup are temperate and dry (deserts, Mediterranean scrub, temperate grasslands), with 2–3 shifts to tropical,seasonally dry forests and grasslands. Most of the variation in phylogenetic structure is explained by long-distance dispersal limitation that is independent of the measured climatic conditions. Sicariinae have an ancientassociation to arid lands, suggesting that PNC prevented them from colonizing mesic habitats. However, nichesare labile at a smaller scale, with several shifts from deserts to SDTFs. This suggests that PNC and long-distancedispersal limitation played major roles in confining lineages to isolated areas of SDTF/desert over evolutionaryhistory, although shifts between xeric biomes occurred whenever geographical opportunities were presented

2.
Mol phylogenet evol ; 140: 106569, 2019.
Artículo en Inglés | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: but-ib17162

RESUMEN

Phylogenetic niche conservatism (PNC) shapes the distribution of organisms by constraining lineages to parti-cular climatic conditions. Conversely, if areas with similar climates are geographically isolated, diversificationmay also be limited by dispersal. Neotropical xeric habitats provide an ideal system to test the relative roles ofclimate and geography on diversification, as they occur in disjunct areas with similar biotas. Sicariinae sandspiders are intimately associated with these xeric environments, particularly seasonally dry tropical forests(SDTFs) and subtropical deserts/scrublands in Africa (Hexophthalma) and the Neotropics (Sicarius). We explorethe role of PNC, geography and biome shifts in their evolution and timing of diversification. We estimated atime-calibrated, total-evidence phylogeny of Sicariinae, and used published distribution records to estimateclimatic niche and biome occupancy. Topologies were used for estimating ancestral niches and biome shifts. Weused variation partitioning methods to test the relative importance of climate and spatially autocorrelatedfactors in explaining the spatial variation in phylogenetic structure ofSicariusacross the Neotropics. NeotropicalSicariusare ancient and split from their African sister-group around 90 (57–131) million years ago. Most spe-ciation events took place in the Miocene. Sicariinae records can be separated in two groups corresponding totemperate/dry and tropical/seasonally dry climates. The ancestral climatic niche of Sicariinae are temperate/dryareas, with 2–3 shifts to tropical/seasonally dry areas inSicarius. Similarly, ancestral biomes occupied by thegroup are temperate and dry (deserts, Mediterranean scrub, temperate grasslands), with 2–3 shifts to tropical,seasonally dry forests and grasslands. Most of the variation in phylogenetic structure is explained by long-distance dispersal limitation that is independent of the measured climatic conditions. Sicariinae have an ancientassociation to arid lands, suggesting that PNC prevented them from colonizing mesic habitats. However, nichesare labile at a smaller scale, with several shifts from deserts to SDTFs. This suggests that PNC and long-distancedispersal limitation played major roles in confining lineages to isolated areas of SDTF/desert over evolutionaryhistory, although shifts between xeric biomes occurred whenever geographical opportunities were presented

4.
Divers. Distrib ; 22(12): p. 1232-1244, 2016.
Artículo | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: but-ib14133

RESUMEN

AimThe knowledge of biodiversity facets such as species composition, distribution and ecological niche is fundamental for the construction of biogeographic hypotheses and conservation strategies. However, the knowledge on these facets is affected by major shortfalls, which are even more pronounced in the tropics. This study aims to evaluate the effect of sampling bias and variation in collection effort on Linnean, Wallacean and Hutchinsonian shortfalls and diversity measures as species richness, endemism and beta-diversity. Location Brazil. MethodsWe have built a database with over 1.5million records of arthropods, vertebrates and angiosperms of Brazil, based on specimens deposited in scientific collections and on the taxonomic literature. We used null models to test the collection bias regarding the proximity to access routes. We also tested the influence of sampling effort on diversity measures by regression models. To investigate the Wallacean shortfall, we modelled the geographic distribution of over 4000 species and compared their observed distribution with models. To quantify the Hutchinsonian shortfall, we used environmental Euclidean distance of the records to identify regions with poorly sampled environmental conditions. To estimate the Linnean shortfall, we measured the similarity of species composition between regions close to and far from access routes. ResultsWe demonstrated that despite the differences in sampling effort, the strong collection bias affects all taxonomic groups equally, generating a pattern of spatially biased sampling effort. This collection pattern contributes greatly to the biodiversity knowledge shortfalls, which directly affects the knowledge on the distribution patterns of diversity. Main conclusionsThe knowledge on species richness, species composition and endemism in the Brazilian biodiversity is strongly biased spatially. Despite differences in sampling effort for each taxonomic group, roadside bias affected them equally. Species composition similarity decreased with the distance from access routes, suggesting collection surveys at sites far from roads could increase the probability of sampling new geographic records or new species


Asunto(s)
Biodiversidad , Ecología
5.
Rev. bras. plantas med ; 17(3): 351-359, Jul-Sep/2015. tab, graf
Artículo en Portugués | LILACS | ID: lil-752562

RESUMEN

Resumo O Estado do Paraná destaca-se pela tradição no cultivo de plantas medicinais. O aumento em sua demanda através da busca de culturas alternativas e rentáveis e o estímulo a uma agricultura ecologicamente sustentável fomentou os agricultores a diversificarem a produção. A pesquisa de campo nos diferentes elos da cadeia produtiva do guaco permitiu construir seu fluxograma, caracterizar o sistema e fluxo de produção, os seus custos e receitas para analisar as Margens e Markups de comercialização. Os sistemas de coleta com enriquecimento e de cultivo apresentaram resultados diferenciados em relação ao seu custo de produção, onde o produtor/coletor alcança uma rentabilidade de 48,9 %, menor margem de comercialização entre todos os elos da cadeia, enquanto o produtor que cultiva o guaco como exploração obtém uma margem de comercialização de 346,4 %. As maiores margens de comercialização (1.733,3 %) estão nos elos fora da porteira das propriedades, percentual entre diferença de preço pago pelo consumidor e o preço recebido pelo produtor/coletor. Os produtores/coletores podem agregar mais renda em vários elos da cadeia produtiva através da organização dos produtores e a melhoria no processo produtivo, possibilitando a melhoria econômica e social nas propriedades familiares, reduzindo o impacto ambiental e garantindo a sustentabilidade dos sistemas de produção.


Abstract The State of Parana stands out for its tradition in the medicinal plants cultivation. The increase of the demand due to the search of alternative and profitable crops and the impulse to an environmentally sustainable agriculture encouraged farmers to diversify production. The field research about the different links of the guaco supply chain allowed the construction of its flowchart, the characterization of the production system and flow, as well as the knowledge of its costs and revenues in order to analyze the commercialization margins and markups. The collection systems with enrichment and the cultivation ones presented different results in relation to its production cost, with the producer/collector reaching a yield of 48.9%, the lowest commercialization margin among all links of the chain, while the farmer who cultivates guaco gets a commercialization margin of 346.4%. The largest commercialization margins (1,733.3%) are in the links outside the properties" gates, as the percentage difference between the price paid by the consumer and the one received by the producer/collector. Producers/collectors can add more income in several links of the supply chain through the producers" organization and by improvements in the production process, enabling the economic and social enhancement at the family farms, thus reducing the environmental impact and ensuring the sustainability of production systems.


Asunto(s)
Comercio/estadística & datos numéricos , Productos Agrícolas/clasificación , Mikania/clasificación , Plantas Medicinales/clasificación
6.
PLoS ONE ; 10(1): p.18, 2015.
Artículo en Inglés | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: but-ib10343
9.
Bull Am Museum Natl Hist ; (388): p.1-60, 2014.
Artículo en Inglés | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: but-ib12851
12.
Zootaxa ; 3599(2): p.101-35, 2013.
Artículo en Inglés | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: but-ib13271
13.
Bull Am Museum Natl Hist ; (370): p.1-68, 2012.
Artículo en Inglés | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: but-ib13125
14.
American Museum Novitates ; (3735): p.1-13, 2012.
Artículo en Inglés | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: but-ib13123
19.
Zootaxa ; (1815): p.51-61, 2008.
Artículo en Inglés | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: but-ib13313
20.
Biotropica ; 39(2): p.221-6, 2007.
Artículo en Inglés | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: but-ib9833
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