Received date: May 13, 2016; Accepted date: June 13, 2016; Published date: June 23, 2016
Citation: Pavan kumar B, Sri Lakshmi, Babu V (2016) Darwin Theory - Evolution of Eukaryotes. J Cytol Histol 7:419. doi:10.4172/2157-7099.1000419
Copyright: © 2016 Pavan Kumar B, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
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Scientist estimated that first life emerged at least 3.8 billion years ago on earth. Which is approximately 750 million years after the formation of Earth. The first cell formed is supposed to have selfreplicating RNA surrounding a membrane of phospholipids and then from then present day prokaryotes such as Archebacteria and eubacteria. The eukaryotes estimated to be evolved 2.7 billion years ago, behind some 1 to 1.5 billion years of prokaryotic expansion.
However, archaebacterial genes are similar to eukaryotes than to that of eubacteria, strengthening the hypothesis that the Archaebacteria and eukaryotes portion a common origin of evolutionary parentage and are more nearby linked to each than eubacteria.
Mainly two types of hypothesis are formulated for the evolution of Eukaryotes, Autogenous and chimeric. Chimeric model is mainly based on endosymbiosis of prokaryotes and autogenous model hypothesis about the invaginations of cell membrane. Autogenous model proposes that in order to increase surface area for diffusion of nutrients cell membrane invaginates to form membraned structures with some DNA in the cytoplasm.
Many has misconception that ‘survival of fittest’ is what the Darwin theory is. The main is essence of this theory is about the adaptability to the surrounding environmental conditions for the survival. So, considering the Darwin’s legacy of evolution, Autogenous hypothesis has more credits over the chimeric model. As in chimeric model one of the organism completely surrenders to the other and the life depends on the host eukaryotic cell which doesn’t make much sense in benefit of survival. Moreover, some protists doesn’t contain mitochondria or chloroplast further strengthening the autogenous hypothesis.