..., queens may be more exposed to the changing environment. Deeper chambers, in contrast, may be climatically more stable, but are more expensive to dig. We investigated the mechanisms underlying the control of nest depth in queens of the leaf-cutting ant Atta vollenweideri . We focused on the use...

...Evie E. Vereecke; Peter Aerts SUMMARY The mechanics of the modern human foot and its specialization for habitual bipedalism are well understood. The windlass mechanism gives it the required stability for propulsion generation, and flattening of the arch and stretching of the plantar aponeurosis...

... region of pigmentation near the anterior tip consisting of concentrated oxyhaemoglobin. A previous investigation of the scanning motion of the ‘head’ and orientation of the ‘neck’ has implicated the shadowing of a photoreceptor inside the tube as the mechanism for identifying the direction of light...

... employed a combination of chemical modification, site-directed mutagenesis and in vitro reassembly. A central question concerns the mechanism by which vacuolar acidification is controlled in eukaryotic cells. We have proposed that disulfide bond formation between conserved cysteine residues...

... progresses, the whole of the PSS and dorsal scutum are lifted together suggesting the action of a locking mechanism. At the bottom of the downstroke there is an opposite, downward rotation of the shelf about its hinge that follows the start of downward scutal movement at the beginning of the upstroke...

...Hans K. Pfau ABSTRACT According to the classical investigation of Boettiger & Furshpan (1952) , the wing beat of flies is accompanied by a bistable mechanism, the ‘click mechanism’. This mechanism is controlled by the pleurosternal and tergopleural muscles (see Heide, 1971 ; Pfau, 1978 ; Pfau...

...A. Roland Ennos ABSTRACT The mechanism of dipteran flight has been investigated in a comparative study involving thorax manipulation, analysis of high-speed films and direct observation of tethered flies under stroboscopic illumination. The click action observed in CCl 4 -anaesthetized Calliphora...

... base articulation has uncovered a wing stop and DVM stretch mechanism. It is argued that there is elastic energy storage during the downstroke which is released on the upstroke. A novel mechanical model for wing movements is proposed which incorporates all the new findings and argues against a ‘click...