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Morphologically differentiated sex chromosomes in neotropical freshwater fish
(2001-12-01)
A general survey of the occurrence of morphologically differentiated sex chromosomes in the neotropical freshwater fishes is presented. The total number of 32 occurrences involving simple XX-XY and ZZ-ZW, and multiple ...
Variability of esterase patterns in adult flies of the saltans species group of Drosophila (subgenus Sophophora)
(Springer, 2009-09-01)
Esterases are known for their involvement in several physiological processes and high degree of polymorphism, in many organisms. Such polymorphism has been used to characterize species and species groups and to study genetic ...
Species-specific PCR for the identification of Cooperia curticei (Nematoda: Trichostrongylidae) in sheep
(Cambridge Univ Press, 2014-12-01)
Agricultural ruminants usually harbour mixed infections of gastrointestinal nematodes. A specific diagnosis is important because distinct species can differ significantly in their fecundity and pathogenicity. Haemonchus ...
Drivers of individual niche variation in coexisting species
(2018-09-01)
Although neglected by classic niche theory, individual variation is now recognized as a prevalent phenomenon in nature with evolutionary and ecological relevance. Recent theory suggests that differences in individual ...
Leaf anatomical traits of non-arboreal savanna species along a gradient of tree encroachment
(Soc Botanica Brasil, 2018-01-01)
In the Brazilian savanna (Cerrado of Brazil), fire suppression has transformed typical savanna formations (TS) into forested savanna (FS) due to the phenomenon of encroachment. Under encroachment, non-arboreal plants begin ...
Comparative foraging behaviour of sympatric Humboldt and Magellanic Penguins reveals species-specific and sex-specific strategies
(Csiro Publishing, 2013-05)
How closely related marine organisms mitigate competition for resources while foraging at sea is not well understood, particularly the relative importance of interspecific and intraspecific mitigation strategies. Using ...