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Thuja plicata is a coniferous tree which displays remarkable water channelling properties. In this article, an easily fabricated mesh inspired by the hierarchical macro surface structure of Thuja plicata branchlets is described which emulates this efficient water collection behaviour. The key parameters are shown to be the pore size, pore angle, mesh rotation, tilt angle (branch droop) and layering (branch overlap). Envisaged societal applications include water harvesting and low cost breathable architecture for developing countries.

This paper assesses whether there have been changes in the magnitude, frequency, duration and seasonality of extreme rainfall over the last 100 years within the middle River Tweed basin, Berwickshire, Scotland. Rainfall patterns are compared with published analyses of other long-term rainfall records to evaluate regional variations in the characteristics of extreme rainfall. Information on the magnitude and frequency of rainfall extremes is used to substantiate and augment a previously established extended flood record for the Whiteadder Water catchment within the middle River Tweed basin.

The drinking behavior of nine captive Phrynocephalus helioscopus was observed. When wetted, animals assumed a stereotyped posture in which the head was depressed to within several mm of the substrate, the limbs splayed, and the hindquarters and tail elevated. Drinking involved repeated, slight tongue protrusion, but without lapping from the substrate. This behavior was elicited in no other context. Simple experiments showed that the interscalar channels transport water across the skin to the mouth by capillary action. This mechanism is compared with that reported for another agamid, Moloch horridus. We hypothesize that the drinking posture 1) facilitates drinking rain water and/or 2) facilitates drinking water condensed on the skin and moved to the mouth by capillary action. We conclude that derived features of water collection and transport shared by Phrynocephalus and Moloch are convergent. Recently, Gans et al. (1982) examined the water-collecting mechanism of Moloch hor- ridus, an Australian agamid squamate. They elaborated upon an earlier study (Bentley and Blumer, 1962) which found that the integument acts as a "blotting paper," soaking up standing water through capil- lary action, ultimately moving it to the