Molecular selection and evolution

It is unlikely that under prebiotic conditions the complex and sophisticated biomacromolecules commonplace in modem biochemistry would have existed. Thus, research into the origin of life is intimately associated with the search for plausible systems that are much simpler than those we see today. However, it is also plausible that these simple building blocks of life might have been amphiphilic molecules in which water could have had an enormous influence on their prebiotic molecular selection and evolution, because water can either form clathrate stmctures or drive these simplest molecules together (Ball, 2001). 

Can a causal connection be shown among molecular self-reproduction, selection, and evolution ... 

Put more simply, when considering prebiotic selection and evolution in the context of the origin of life, the enormously powerful force of water must never be underestimated. As all life is based on water, all molecules in living systems interact with it, and water likely has driven molecular evolution from the very beginning, here on earth or plausibly elsewhere in the universe - or multiverse. 

Y.-H. and Vacquier, V.D. (1995). Evolution and systematics in Haliotidae (Mollusca, Gastropoda) Inferences from DNA sequences of sperm lysin. Marine Biology 724 267-279. Y.-H., Ota,T., and Vacquier, V.D. (1995). Positive selection is a general phenomenon in the evolution of abalone sperm lysin. Molecular Biology and Evolution 72 231-239. 

Kiippers, B., 1975, The general principles of selection and evolution at the molecular level. Prog. Biophys. Molec. Biol. 30 1. 

Among the numerous challenges faced in understanding the formation and evolution of hierarchical structures in polymer crystallization, we restrict ourselves to explain the essential basic features of folded lamellae. Specihcally, we consider (1) molecular origin of enhanced scattered intensity before any crystallographic features are apparent, (2) spontaneous selection of small lamellar thickness, (3) molecular details of growth front, and (4) formation of shish-kebab structures in the presence of a flow. 

Activation energies are energy barriers to chemical reactions. These barriers are crucial to life itself. The rate at which a molecule undergoes a particular reaction decreases as the activation barrier for that reaction increases. Without such energy barriers, complex macromolecules would revert spontaneously to much simpler molecular forms, and the complex and highly ordered structures and metabolic processes of cells could not exist. Over the course of evolution, enzymes have developed lower activation energies selectively for reactions that are needed for cell survival. 

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