Space-time dilation as well as relativity generally refer to Einstein's general theory. In fact, many works inspired by dimensionless engineering and physics use a somewhat similar approach to building scale models. This approach has already been adapted to ethology to compare animals of different sizes or estimate the behavior of extinct species. But this is the ""little end of the telescope"" and the dimensionless approach allows so much more. Through various studies that we conducted or found in the literature, I'll show how a dimensionless approach makes it possible to discern the influence of the physical, mechanical or chemical aspects of the environments in which living organisms behave. This paradigm is also suitable to conduct an integrative approach to a phenomenon and to understand the different sized worlds we study.