Fromneontstofiliontsand their progenies...

Abstract

"Should the question of the priority of the egg over the chicken, or of the chicken over the egg disturb you, it is because you assume that animals were originally what they are to-day; what madness!" The dream of d'Alembert, 1760, Denis DiderotAbstract. Since the origins, different modes of life exist. Indeed it is difficult to imagine how things could have been constructed by a single event that would have marked the birth of life. A brief historical background of the subject will be presented here. Then, we shall wander through the history of the discoveries that have led the way of experimental science over the last 150 years and shall dwell on one of the major paradigms, that of the RNA World. This paradigm illustrates the path followed by the living that tries all possible means when expressed at the molecular level as simple free molecule leading to RNA fragments and to modern subviral particles such as viroids then to ramifications and compartments. Between the ancient and the modern RNA world we underline how environment talks to molecules leading to the global living tissus which establish the ground of biodiversity.

The quest for the origins in evolutionary biology

“…Big questions such as the origin of Life or the origin of Man, are often treated as if such entities appeared from nothing, because Life, Man or his cultural traits are generally considered as completely different from anterior stages that would belong to another universe. This is for instance why the transition between the chemical world and the biological world is so much questioned [4][5][6][7]. This is also why the subject of synthetic Life is so striking as if it is an impossible or inacceptable performance for us to produce Life by ourselves [8,9].…”

“…-To understand the origin of life and in the absence of detailed knowledge on the prebiotic environment and stages, biogenesis experiments are conducted, putting together the materials and the environment supposedly present, four billions years ago, to explore the possible working processes [4][5][6][7]. -Some terrestrial regions may be essential to understand the evolution of specific distributions or regional climates but these regions could have been subducted and melted by tectonic plates, or very rapidly eroded in ancient times.…”