Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 3

Liczba wyników na stronie
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych:  multiannual variation
help Sortuj według:

help Ogranicz wyniki do:
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
To examine multi-annual variations in the food habits of the Japanese marten (Martes melampus), we analyzed the composition of marten feces in the Bonbori Forest Path in western Tokyo, central Japan, in two time periods a decade apart (1997–1998 and 2007–2008). The staple foods of martens in both periods were fruits/seeds and animal materials (mainly insects and mammals). The martens fed frequently on fruits/seeds and insects throughout the year in both periods, but the consumption of mammals, birds, and arthropods/other animals showed seasonal variations. The composition of fruits/seeds and the frequency of occurrence for each fruit-bearing species differed between the two periods. These results suggest that both the foraging strategy and role of martens as a seed dispersal agent changes yearly, presumably according to multi-annual variation in the availability of prey animals and/or fruits. We emphasize the importance of multi-annual studies both on food habits and to monitor food availability in the temperate region where the food environment changes among seasons, as well as years.
Multiannual variation is one of several types of species morphological variability, one that is directly related to ecophenotypic and evolutionary responses to changing environments. The morphology of small mammal populations can change quickly because generation length is short, usually one year, and individual lifespans are often only a year or two. We studied the response of skull and mandible morphology in the common shrew Sorex araneus Linnaeus, 1758 to nine climate factors related to snow cover, temperature and precipitation at a study site near Syktyvkar, Russia through the period 1976 to 2003. We found that these multivariate phenotypes changed significantly from year to year, though there were no clear directional trends in the change. The phenotype itself was closely associated with the range of annual temperature and winter precipitation. Changes in summer temperatures and precipitation seem to drive change in size-related phenotypes, whereas changes in snow cover and winter temperature seem to drive change in shape.
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.