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1.
Science ; 375(6586): 1275-1281, 2022 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-35298255

RESUMO

Urbanization transforms environments in ways that alter biological evolution. We examined whether urban environmental change drives parallel evolution by sampling 110,019 white clover plants from 6169 populations in 160 cities globally. Plants were assayed for a Mendelian antiherbivore defense that also affects tolerance to abiotic stressors. Urban-rural gradients were associated with the evolution of clines in defense in 47% of cities throughout the world. Variation in the strength of clines was explained by environmental changes in drought stress and vegetation cover that varied among cities. Sequencing 2074 genomes from 26 cities revealed that the evolution of urban-rural clines was best explained by adaptive evolution, but the degree of parallel adaptation varied among cities. Our results demonstrate that urbanization leads to adaptation at a global scale.


Assuntos
Adaptação Fisiológica , Evolução Biológica , Ecossistema , Trifolium/fisiologia , Urbanização , Cidades , Genes de Plantas , Genoma de Planta , Cianeto de Hidrogênio/metabolismo , População Rural , Trifolium/genética
2.
Zookeys ; (642): 131-148, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28138302

RESUMO

Eight species of falcons (Falconidae) have been recorded in Chile. To date, all relevant studies considered birds of prey in general, with no specific focus on this family. Based on a comprehensive review of the literature, an updated report is presented on the state of knowledge of falcons in Chile. This data set comprises a total of 165 studies published from 1915 to 2015. Scientific productivity was lowest in 1945-1955 and highest in 2005-2015, with a steady increase since 1985. However, the focus of research in Chile is biased towards two species: Milvago chimango and Falco sparverius. Two administrative regions, Santiago Metropolitan Region and Araucanía, were the most studied whereas Arica, Tarapacá, and Antofagasta regions accounted for fewer than 1% of the studies. Faunistic studies (including abundance) were the most common research topic. It is suggested that the lack of knowledge regarding species in the genus Phalcoboenus may negatively affect the conservation status of these species, and believed that the lack of preference for certain research topics, such as systematics and natural history, are the result of historical factors including the decrease of field biology and perhaps a biased interest of the researchers. Finally, this review highlights the paucity of information on falcons and provides a framework for directing future research.

3.
Ecotoxicol Environ Saf ; 101: 220-5, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24507149

RESUMO

Field studies and laboratory experiments were conducted to assess the impact of elevated nitrate (NO(3)(¯)) concentrations on the European endangered white-clawed crayfish Austropotamobius italicus (Faxon) in the Henares River Basin (Central Spain), within an area that is vulnerable to nitrate pollution. Two sampling surveys were carried out in the summer of 2009 and 2011 to collect freshwater crayfish at eight sampling sites along this vulnerable area. The invasive read-swamp crayfish Procambarus clarkii (Girard) was the only collected crayfish species. Nitrate toxicity experiments however showed that A. italicus is one of the most tolerant species to nitrate toxicity. Although the food consumption was the most sensitive endpoint to nitrate toxicity (followed by the escape response and mortality), the no-observed-effect concentration (NOEC) for this endpoint after 14 days of exposure to nitrate was as high as 100mg NO(3)(¯)N/l, with some crayfish being still alive after fourteen days of exposure to a nominal nitrate concentration of 800mg NO(3)(-)N/l. Besides, a safe concentration of nitrate for A. italicus, along with its respective 95% confidence limits, were estimated to be 68.5 (22.4-187) mg (NO(3)(¯)N/l. Overall we conclude that elevated nitrate concentrations would not be responsible for the absence of white-clawed crayfish in the Henares River Basin. Other environmental factors, particularly the presence of P. clarkii and its fungal pathogen, would be major causes.


Assuntos
Astacoidea/efeitos dos fármacos , Ecotoxicologia , Nitratos/toxicidade , Rios , Poluentes Químicos da Água/toxicidade , Animais , Dose Letal Mediana , Espanha
4.
Rev. biol. trop ; 54(4): 1085-1091, dic. 2006. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-492177

RESUMO

The structure and ultra-structure of the eggs from Ormiscodes socialis (Feisthamel) and Polythysana cinerascens (Philippi) are described, considering shape, size, coloring when recently laid, oviposition type and aeropiles (quantity, distribution and proportion) in the micropilar area, among others. The ultra-structure is shown for primary cells, secondary cells, aeropiles and micropiles. A comparative table of the eggs of these species is presented and includes the previously described eggs of Adetomeris microphthalma (Philippi). Myoschilos oblonga Ruiz y Pavón (Santalaceae) is recorded as a new host for P. cinerascens.


Se describe la estructura y ultraestructura de los huevos de las especies Ormiscodes socialis (Feisthamel) y Polythysana cinerascens (Philippi), considerando la forma, tamaño, color, tipo de ovipostura, y aeropilas (cantidad, distribución y proporción) en el área micropilar, entre otros. La ultraestructura es mostrada a través de las celdas primarias, celdas secundarias, aeropilas y micropilas; además se incluye a la especie ya descrita Adetomeris microphthalma (Philippi) y se confecciona un cuadro comparativo para los huevos de estas especies. Se registra como nuevo hospedero de P. Cinerascens a Myoschilos oblonga Ruiz y Pavón (Santalaceae).


Assuntos
Animais , Mariposas/ultraestrutura , Óvulo/ultraestrutura , Chile , Mariposas/classificação , Microscopia Eletrônica de Varredura
5.
Rev Biol Trop ; 54(4): 1085-91, 2006 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-18457143

RESUMO

The structure and ultra-structure of the eggs from Ormiscodes socialis (Feisthamel) and Polythysana cinerascens (Philippi) are described, considering shape, size, coloring when recently laid, oviposition type and aeropiles (quantity, distribution and proportion) in the micropilar area, among others. The ultra-structure is shown for primary cells, secondary cells, aeropiles and micropiles. A comparative table of the eggs of these species is presented and includes the previously described eggs of Adetomeris microphthalma (Philippi). Myoschilos oblonga Ruiz y Pavón (Santalaceae) is recorded as a new host for P. cinerascens.


Assuntos
Mariposas/ultraestrutura , Óvulo/ultraestrutura , Animais , Chile , Microscopia Eletrônica de Varredura , Mariposas/classificação
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