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Selection at constant selective pressures results in the optimization of the average productivity within the system and an increase in the information content. The entropy increase through evolutionary time is, therefore, minimized. The “pattern” of entropy descriptions for ontogenetic (developmental) and phylogenetic (evolutionary) changes is shown to be different, and the latter is consistent with...
Chemical data are given forSciadophyton, Eogaspesiea,Lepidodendropsis, Triphyllopteris, Chlidanophyton andDrepanophycus. The participation of these taxa within clustering analysis is shown to generate a cluster referable tentatively to the lycopods. Introgression of clusters representative of some major plant groups (e.g., zosterophyllophytes with the lycopods, and the trimerophytes with the progymnosperms)...
A model for speciation is given in which a taxon’s phenotypic variation and concomitant variation in fitness are related to gradients within the environment. Phenotypic expressions within the population are shown to undergo abrupt transitions as a result of discontinuous fitness-functions. Evidence for rapid and abrupt phenotypic variation is explored by analyses of speciation (= origination) rates...
An attempt is made to estimate a mathematical expression for the underlying mean rate of evolution in organic systems, and in particular those of various plant groupings. This was done by considering the thermodynamic constraints on any system tending towards greater levels of complexity with time (or showing a progressive decrease in randomness). Orderliness is here equated with genetic-information,...
The organic chemical constituents of compression fossils ofNematothallus,Spongiophyton, Orestovia andEohostimella are identified and compared with those isolated from living and fossil forms ofBotryococcus (a green alga) andTaeniocrada (a vascular plant fossil). The range and maxima in the carbon numbers observed in the normal, saturated acids isolated fromNematothallus, Orestovia, andSpongiophyton...
The chemical compositions of plant fossils having trimerophyte (Pertica,Psilophyton princeps, P. cf.jorbesii), rhyniophyte (Taeniocrada), and zosterophyll (Sawdonia) morphological characteristics are chemically analyzed and chemotaxonomically related to vascular ( ?Eohostimella, Renalia, Chahuria) and putative non-vascular plant fossils (Botryococcus, Parka, Pachytheca, Prototaxites,Nematothallus, Spongiophyton, Protosalvinia, Orestovia...
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