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-(Fruit production and spatial distribution of animal-dispersed angiosperms in a Mixed Ombrophilous Forest in State of Rio Grande do Sul, Brazil). We investigated, during 14 months, patterns of fruit production of animal dispersed angiosperms in a patch of Mixed Ombrophilous Forest (MOF) in the National Park of Aparados da Serra, State of Rio Grande do Sul, south Brazil. For a total of 570 individuals sampled in a 2.56 ha area we identified 27 species of animal dispersed angiosperms (13 families). The most abundant families were: Myrtaceae (eight species), Melastomataceae, Solanaceae, and Rubiaceae (three species each). Most sampled life forms were shrubs (46.0% of all individuals 37.0% of species total), followed by treelets (31.9% and 22.2%), herbs (10.2% and 18.5%), trees (8.7% and 18.5%), and epiphytes (3.2% and 3.7%). Red (22.2%) and orange (18.5%) fruits prevailed, as well as small fruits (70% of fruit total with size of 1-10 mm × 1-10 mm), and fruits with one to ten small seeds (96% of total species with seed size of 1-10 mm × 1-10 mm). The three species that produced the greatest amount of fruits were: Myrceugenia miersiana (Gardner) D. Legrand & Kausel (Myrtaceae) (tree -61.0% of total production of fruits), and the melastomes Leandra variabilis Cogn. (shrub -18.1%) and Miconia cinerascens Miq. (shrub -8.6%). These species showed an aggregated dispersion pattern (Standardized Morisita index > 0.5 for all of them). The monthly number of fruiting species was significantly correlated with monthly temperature in the same month (r s = 0,70; p < 0,01), and with rainfall in the previous month (r s = 0,67; p < 0,02). The seed production of Araucaria angustifolia (Bertol.) Kuntze occurred during the period with the lowest number of angiosperm species producing animal-dispersed fruits. This non-overlapping between events might favor the occurrence of frugivorous animals, enabling a higher resource offer during the entire year.

We investigated the relation between temperature and diel activity patterns of Necromys lasiurus (Lund, 1841) in 10 sites of open vegetation (grassland fields) in the Cerrado (savanna-like vegetation) of central Brazil. We used live traps equipped with timing devices during two trapping sessions: in the end of the dry season (session 1, October 2001) and in the wet season (session 2, January–February 2002). Necromys lasiurus is basically a diurnal rodent with more pronounced crepuscular and nocturnal activity in the dry season than in the wet season. Only in the wet season did we detect significant between-gender differences, with males being less active than females in the first hours after sunrise but more active between 0900 and 1200. There was no significant activity–temperature relation in the dry season, but in the wet season, both genders showed a positive relation between ambient temperature and activity. Individuals might be avoiding hot midday hours in the end of the dry season to minimize time exposure to a physiologically stressful condition caused by the joint action of high temperatures and extremely low relative humidity (<15%). In the rainy season, the high relative humidity (80%–90%) might allow the animals to show a positive relation between activity and ambient temperature.

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