The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Isometric growth of larval insect midgut predicts that the ratio of midgut surface area to body mass decreases as larvae grow. Gut tissue and gut content masses were measured in first through fifth instar Manduca sexta larvae. Wet mass of gut tissue increased in relationship to body mass with a scaling exponent of 0.85 compared to an exponent of 1.33 for gut content mass, suggesting that surface area...
Aphids exhibit several polyphenisms in which discontinuous, alternative phenotypes are produced depending on environmental conditions. One representative example is the wing polyphenism, where winged and wingless females are produced through parthenogenesis. Previous work has shown that, in some aphid species, the density condition sensed by the mother aphid determines the developmental fate of embryos...
We studied the variation of thermal parameters of Odontophrynus occidentalis between season (wet and dry) in the Monte desert (Argentina). We measured body temperatures, microhabitat temperatures, and operative temperatures; while in the laboratory, we measured the selected body temperatures. Our results show a change in the thermal parameters of O. occidentalis that is related to environmental constraints...
Snakes have long been thought to drink with a two‐phase buccal‐pump mechanism, but observations that some snakes can drink without sealing the margins of their mouths suggest that buccal pumping may not be the only drinking mechanism used by snakes. Here, we report that some snakes appear to drink using sponge‐like qualities of specific regions of the oropharyngeal and esophageal mucosa and sponge‐compressing...
We aimed to evaluate the responses of cortisol, corticosterone, and blood glucose to adrenocorticotropic hormone (ACTH) in males and females of the subterranean rodent Ctenomys talarum and addressed interannual variations in the plasma levels of both hormones. The most important results indicate that: (1) cortisol positively responds to the ACTH signal but corticosterone does not, even though corticosterone...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.