Social status, activity and preputial glands of wild and domestic house mice

Scent marking by deposition of urine, and the preputial glands, of adult, male, wild house mice, Mus mmmlus L., were studied and compared with those of an outbred domestic strain. The preputial glands of dominant wild mice were always heavier than those of subordinates. No dominance relationships could be established among the domestic mice. For study of scent marking each mouse was observed singly in a residential maze. Dominant wild mice marked more than the subordinates. The domestic mice scent-marked much less even than the subordinate wild mice. Subordinate wild mice spent less time than the dominant wild mice outside the nest; but the number of excursions outside the nest made by the subordinates resembled that of the dominants. Hence social status influenced the pattern of movements in a structured environment.     

The new-object and new-place reactions of Rattus rattus L

The behaviour of the wild "black" or "house" rat, Rattus rattus L., was studied in an artificial environment, a plus-maze. The maze consisted of a central nest box and four arms. Food and water were placed at the ends of different arms, and movements of the rats were recorded automatically. A detailed analysis was made of habituation to the artificial environment and of the patterns of activity displayed there. Rats were most active during the dark phase of 'he light cycle; they displayed a bimodal pattern of visits to and time spent in the arms, with peaks around three hours after lights off and four hours before lights on. Reaction to new objects and places was measured in several ways. The rats usually avoided new objects placed in a familiar area, but showed little hesitation to explore a previously inaccessible area. Rats generally stopped avoiding new objects in the feeding area within one to two days, even when an alternative source of food was available elsewhere. There was, however, much variation.
The methods used allow study of two distinct initial responses to novelty, each clearly displayed: (a) withdrawal from a strange object in a familiar place ("fear"), and (b) approach to a newly accessible area ("curiosity"). Behaviour often depends on the interaction between these two processes.     

Langenheim, J.H. Plant resins: chemistry, evolution, ecology and ethnobotany.

When I agreed to review this book, I did so because I thoughtit would be an opportunity to bring myself up-to-date in a fieldI felt I ought to know more about. I had no idea that it wouldmake such compulsive reading. Jean Langenheim has spent hercareer working on plant resins and she has done a great serviceby assembling her wealth of knowledge and experience into thismarvellous book. The blandness of the title     

A seasonal cycle of cell wall structure is accompanied by a cyclical rearrangement of cortical microtubules in fusiform cambial cells within taproots of Aesculus hippocastanum (Hippocastanaceae)

Aspects of the structure and ultrastructure of the fusiform cambial cells of the taproot of Aesculus hippocastanum L. (horse chestnut) are described in relation to the seasonal cycle of cambial activity and dormancy. Particular attention is directed at cell walls and the microtubule and microfilament components of the cytoskeleton, using a range of cytochemical and immunolocalization techniques at the optical and electron-microscopical levels. During the dormant phase, cambial cell walls are thick and multi-layered, the cells possess a helical array of cortical microtubules, and microfilament bundles are oriented axially. In the early stages of reactivation, vesicle-like profiles are associated with the cell walls, whereas arrangement of the cytoskeletal elements remains unchanged. In the succeeding active phase, the cell walls are thin, and cortical microtubules form a random array, although microfilament bundles maintain a near-axial orientation. The observations are discussed in relation to the seasonal cycle of wall structure and cortical microtubule rearrangement within the vascular cambium of hardwood trees. It is suggested that the cell-wall thickening at the onset of cambial dormancy, which is associated with the presence of a helical cortical microtubule array, should be considered to be secondary wall thickening, and that selective lysis of this secondary wall layer during cambial reactivation restores the thinner, primary wall found around active cambial cells.