Abstract
ABSTRACT The humidity reactions of Oniscus asellus, Porcellio scaber and Armadillidium vulgare have been analysed and compared. The mechanism whereby the three species collect in moist air is twofold, Consisting of (a) hygrokinesis, or decrease in activity and speed in moist air, and (b) of more frequent turnings in space, retaining them in the areas of greater humidity. These mechanisms are most clearly expressed in Oniscus asellus and least in Armadillidium vulgare. This sequence may be correlated with the resistance to desiccation of the three species, which is greatest in Armadillidium vulgare, and greater in Porcellio scaber than in Oniscus asellus. It is suggested that the humidity reactions of isopods are controlled by water loss by evaporation from the whole body. A correlation between hygrokinesis and thigmokinesis was observed in Porcellio scaber. There appears to be a reversal from negative to positive phototaxis in Oniscus asellus, correlated with the water loss by evaporation. The humidity reactions, low thigmokinesis and negative phototaxis combine to retain the isopods in damp, dark habitats.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
