In 1895, well over 100 years ago, Willem Roux published his collected works on the developmental mechanics
of organisms in 2 volumes. Volume 1 is largely dedicated to functional adaptation and is a condensation of his
investigations into causes of the size and shape of organs and tissues, postulating the influence of functional
demand, mediated by mechanical stimuli, on the shaping of organs and tissues. In this classic work he contributed
to the understanding of the control of the structural development and organisation of blood vessels, muscles and
bone. This work has been a source of inspiration for many investigators over the years. Well known examples
are Wolff's law and Pauwel's theory on trajectories. Over the past 2 decades these hypotheses and concepts have
been reappraised using 2 main approaches. Firstly, in muscles and tendons a qualitative approach with classical
Newtonian mechanics combined with the anatomical configuration of these structures has been used to study
the direction and the nature of the mechanical stresses in the tissues, be they compressive, tensile or shear. In
bone and blood vessels these stresses are less accessible and often require computer modelling to calculate the
mechanics at a cellular level. Secondly, molecular biology has demonstrated, both in tissue culture and in animal
experiments, that mechanical stimuli can bring about cascades of messages in and between cells, but the
experimental control of mechanical stresses in biological experiments is far from simple and limits the conclusions
that can be derived. In order to approach a complete picture, the gap between these 2 approaches must be
bridged. In this respect modern imaging techniques are helpful because they offer the possibility of studying the
shape and change of shape over time in living organisms in greater detail.
The Symposium was organised in such a way that for different tissues recent advances using different
approaches could be presented, helping to identify future directions for this field of morphological research.
Review articles based on 2 of the 6 contributions to the Symposium are published here. One has already appeared
(Benjamin & Ralphs, J. Anat. 193, pp. 481–494).