Consulta: subjectFacets:"Life histories"
Registros recuperados: 2
Data/hora: 10/06/2024 09:01:02

Contribution of Inbreeding to Extinction Risk in Threatened Species
Provedor de dados: 7
Autores: Brook, Barry W; Northern Territory University; barry.brook@ntu.edu.au; Tonkyn, David W; Clemson University; tdavid@clemson.edu; O'Grady, Julian J; Macquarie University; jogrady@rna.bio.mq.edu.au; Frankham, Richard; Macquarie University; rfrankha@rna.bio.mq.edu.au.
Wild populations face threats both from deterministic factors, e.g., habitat loss, overexploitation, pollution, and introduced species, and from stochastic events of a demographic, genetic, and environmental nature, including catastrophes. Inbreeding reduces reproductive fitness in naturally outbreeding species, but its role in extinctions of wild populations is controversial. To evaluate critically the role of inbreeding in extinction, we conducted realistic population viability analyses of 20 threatened species, with and without inbreeding depression, using initial population sizes of 50, 250, and 1000. Inbreeding markedly decreased median times to extinction by 28.5, 30.5, and 25% for initial populations of 50, 250, and 1000, respectively, and the...
Tipo: Peer-Reviewed Reports
Palavras-chave: Endangered species; Inbreeding depression; Life histories; Median time to extinction; Population viability analysis; Purging.
Ano: 2002

All green, but equal? Morphological traits and ecological implications on spores of three species of mosses in the Brazilian Atlantic forest
Provedor de dados: 42
Autores: MACIEL-SILVA,ADAÍSES S.; SILVA,FLÁVIA C.L. DA; VÁLIO,IVANY F.M.
Spores of the tropical mosses Pyrrhobryum spiniforme, Neckeropsis undulata and N. disticha were characterized regarding size, number per capsule and viability. Chemical substances were analyzed for P. spiniforme and N. undulata spores. Length of sporophyte seta (spore dispersal ability) was analyzed for P. spiniforme. Four to six colonies per species in each site (lowland and highland areas of an Atlantic Forest; Serra do Mar State Park, Brazil) were visited for the collection of capsules (2008 – 2009). Neckeropsis undulata in the highland area produced the largest spores (ca. 19 µm) with the highest viability. The smallest spores were found in N. disticha in the lowland (ca. 13 µm). Pyrrhobryum spiniforme produced more spores per capsule in the highland...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Bryophytes; Histochemistry; Life histories; Spore size; Spore production; Tropical rain forest.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652014000301249