Evolution of Life

Author(s):  
Robin Dunbar

Can we say how life on earth started? The origins of life on earth must predate the earliest fossils, and presumably must be simpler in form than even those earliest fossils. It is very unlikely that we will ever know what these life forms were,...

2021 ◽  
Vol 9 (11) ◽  
pp. 235-251
Author(s):  
Y. V. Subba Rao

              The current hypothesis leads to the panspermia origin of life, which is based on the scientific principle of electromagnetic force interaction with matter. Electromagnetic force (Sunlight) interacts with inorganic chemistry available to us given out by the stars in the universe plausibly triggers the formation of extra-terrestrial biological molecules of proto cells under abiotic conditions, as evidenced by their presence in meteorites.' Proto cells’ might theoretically give rise to living organisms with a manifested soul, allowing 'Ribose' to be formed from ice grains hit by sunlight for RNA and DNA at the same time. The presence of life's building blocks and other important organic chemicals like ribose in meteorites, including some microscopic life forms that aren't native to Earth, may have led to the 'Panspermia Origin of Life' and the 'Evolution of Life on Earth' which is evidenced by the definition of 'Meteorites' in Vedic Scriptures, such as the "Bhagavad Gita" (3000 BC) and "Brihat Samhita" (520 AD) that they are the souls of righteous people who have returned to earth to be reborn.


Geology ◽  
2020 ◽  
Vol 48 (10) ◽  
pp. 1018-1022
Author(s):  
Indrani Mukherjee ◽  
Ross R. Large

Abstract The significance of trace elements in initiating origins and driving evolution of life on Earth is indisputable. Trace element (TE) trends in the oceans through time broadly reflect their availability and allow speculation on all possible influences on early life. A comprehensive sedimentary pyrite–TE database, covering 3000 m.y. of the Precambrian, has improved our understanding of the sequence of bio-essential TE availability in the ocean. This study probed how changing availability (and scarcity) of critical TEs in the marine environment influenced early life. The pyrite-shale matrix TE sequence shows relatively elevated concentrations of Ni, Co, Cu, and Fe, Cr, respectively, in the Archean and Paleoproterozoic. Abundances of these elements in the Archean potentially facilitated their widespread utilization by prokaryotes. The Paleoproterozoic–Mesoproterozoic saw increases in Zn and Mo but a marked decline in Ni, Co, Cu, Se, and Fe. Our data suggest the evolution of the first complex cell in the Paleoproterozoic was probably triggered by this major change in TE composition of the oceans. A decline of elements prompted alternative utilization strategies by organisms as a response to TE deficits in the middle Proterozoic. An overall increase in a multitude of elements (Ni, Co, Cu, Cr, Se, V, Mo, and P) in the Neoproterozoic and Cambrian was highly advantageous to the various micro– and macro–life forms. Without questioning the importance of macronutrients and atmosphere-ocean redox state, multi-TE availability would have induced substantial heterogenous biological responses, owing to the effects of optimal, deficient, toxic, lethal, and survival levels of TEs on life.


Pyrite ◽  
2015 ◽  
Author(s):  
David Rickard

If you have been reading this book since the beginning, you will not be surprised by now to find that you have come across a chapter documenting the involvement of pyrite in the origin of life. This is because you will have read in this book how pyrite has been at the root of many fundamental discoveries about the nature of our world. So you do not suffer more than eyebrow-raising surprise and maybe a gentle throat-clearing in learning that pyrite is contributing to our current understanding of the origins of life. By contrast, if you have dived in at Chapter 9 you probably look at the title of this chapter with disbelief. After all, what could be the connection between a common glitzy mineral and the origin of life? The more diligent reader will have already learned that pyrite formation is intimately associated with biology because most of it is produced by bacteria that extract their oxygen from sulfate and produce hydrogen sulfide. This relationship is so overweening today that pyrite formation controls many fundamental aspects of the Earth’s environment. So what happens if we extend this line of inquiry back to the beginnings of geologic time? We have already seen that the characteristics of ancient pyrite are one of the main sources of information about the nature of the early Earth. The consequence of this is that we know quite a bit about the relationship between pyrite and early life on Earth. In this chapter, we further explore this and review the laboratory work that implicates pyrite itself in the original syntheses of the self-replicating biomolecules that assembled to produce Earth’s first life forms. The thesis that life developed from nonbiological chemistry is a very old idea stretching back through Anaximander in 6th-century BCE Greece to the Vedic writings of ancient India around 1500 BCE and is often called abiogenesis.


2020 ◽  
Vol 13 (1) ◽  
pp. 3-15
Author(s):  
Arunachalam Vasanthanathan ◽  
Uthirakumar Siddharth ◽  
Manivannan Vignesh ◽  
Radhakrishnan Pravin

Background: Nature has always played a vital role in the evolution of life forms. The design of products in accordance with nature’s design, popularly known as biomimicry, had played a vital role in pushing the technology and product effectiveness to the next level. Humans have long sought to mimic not just the design, but also the methodology adopted by certain animals. For example, the walking technique of vertebrates has been effectively mimicked for a quadruped robot to make a system more efficient by consuming less power. Thus indirectly, nature acts as a driving factor in pushing technological growth. Methods: The principle objective of this paper is to provide an overview of popular bio mimicked products inspired by nature. This paper emphasizes a wide variety of products developed in the field of materials inspired by nature. Results: Wall-climbing robots, Sonar, X-ray imaging, Sandwich and Honeycomb structures are some of the popular products and designs inspired by nature. They have resulted in better designs, better products with improved efficiency and thus have proven to be better alternatives. Some products and designs such as Samara drone, Riblet surfaces, DSSCs, Biomimetic Drills and Water turbines have plenty of scopes to replace conventional products and designs. Conclusion: While plenty of products, structures and designs have successfully replaced older alternatives, there is still a large scope for biomimicry where it could potentially replace conventional products and designs to offer better efficiency.


2014 ◽  
Vol 57 (5) ◽  
pp. 897-902 ◽  
Author(s):  
AnHuai Lu ◽  
Xin Wang ◽  
Yan Li ◽  
HongRui Ding ◽  
ChangQiu Wang ◽  
...  

2012 ◽  
Vol 9 (6) ◽  
pp. 2275-2286 ◽  
Author(s):  
J. Wierzchos ◽  
A. F. Davila ◽  
I. M. Sánchez-Almazo ◽  
M. Hajnos ◽  
R. Swieboda ◽  
...  

Abstract. The hyperarid core of the Atacama Desert, Chile, is possibly the driest and most life-limited place on Earth, yet endolithic microorganisms thrive inside halite pinnacles that are part of ancient salt flats. The existence of this microbial community in an environment that excludes any other life forms suggests biological adaptation to high salinity and desiccation stress, and indicates an alternative source of water for life other than rainfall, fog or dew. Here, we show that halite endoliths obtain liquid water through spontaneous capillary condensation at relative humidity (RH) much lower than the deliquescence RH of NaCl. We describe how this condensation could occur inside nano-pores smaller than 100 nm, in a newly characterized halite phase that is intimately associated with the endolithic aggregates. This nano-porous phase helps retain liquid water for long periods of time by preventing its evaporation even in conditions of utmost dryness. Our results explain how life has colonized and adapted to one of the most extreme environments on our planet, expanding the water activity envelope for life on Earth, and broadening the spectrum of possible habitats for life beyond our planet.


2016 ◽  
Vol 16 (1) ◽  
pp. 40-59 ◽  
Author(s):  
Claudio Maccone

AbstractIn two recent papers (Maccone 2013, 2014) as well as in the book (Maccone 2012), this author described the Evolution of life on Earth over the last 3.5 billion years as a lognormal stochastic process in the increasing number of living Species. In (Maccone 2012, 2013), the process used was ‘Geometric Brownian Motion’ (GBM), largely used in Financial Mathematics (Black-Sholes models). The GBM mean value, also called ‘the trend’, always is an exponential in time and this fact corresponds to the so-called ‘Malthusian growth’ typical of population genetics. In (Maccone 2014), the author made an important generalization of his theory by extending it to lognormal stochastic processes having an arbitrary trend mL(t), rather than just a simple exponential trend as the GBM have.The author named ‘Evo-SETI’ (Evolution and SETI) his theory inasmuch as it may be used not only to describe the full evolution of life on Earth from RNA to modern human societies, but also the possible evolution of life on exoplanets, thus leading to SETI, the current Search for ExtraTerrestrial Intelligence. In the Evo-SETI Theory, the life of a living being (let it be a cell or an animal or a human or a Civilization of humans or even an ET Civilization) is represented by a b-lognormal, i.e. a lognormal probability density function starting at a precise instant b (‘birth’) then increasing up to a peak-time p, then decreasing to a senility-time s (the descending inflexion point) and then continuing as a straight line down to the death-time d (‘finite b-lognormal’).(1)Having so said, the present paper describes the further mathematical advances made by this author in 2014–2015, and is divided in two halves: Part One, devoted to new mathematical results about the History of Civilizations as b-lognormals, and(2)Part Two, about the applications of the Evo-SETI Theory to the Molecular Clock, well known to evolutionary geneticists since 50 years: the idea is that our EvoEntropy grows linearly in time just as the molecular clock. (a)Summarizing the new results contained in this paper: In Part One, we start from the History Formulae already given in (Maccone 2012, 2013) and improve them by showing that it is possible to determine the b-lognormal not only by assigning its birth, senility and death, but rather by assigning birth, peak and death (BPD Theorem: no assigned senility). This is precisely what usually happens in History, when the life of a VIP is summarized by giving birth time, death time, and the date of the peak of activity in between them, from which the senility may then be calculated (approximately only, not exactly). One might even conceive a b-scalene (triangle) probability density just centred on these three points (b, p, d) and we derive the relevant equations. As for the uniform distribution between birth and death only, that is clearly the minimal description of someone's life, we compare it with both the b-lognormal and the b-scalene by comparing the Shannon Entropy of each, which is the measure of how much information each of them conveys. Finally we prove that the Central Limit Theorem (CLT) of Statistics becomes a new ‘E-Pluribus-Unum’ Theorem of the Evo-SETI Theory, giving formulae by which it is possible to find the b-lognormal of the History of a Civilization C if the lives of its Citizens Ci are known, even if only in the form of birth and death for the vast majority of the Citizens.(b)In Part Two, we firstly prove the crucial Peak-Locus Theorem for any given trend mL(t) and not just for the GBM exponential. Then we show that the resulting Evo-Entropy grows exactly linearly in time if the trend is the exponential GMB trend.(c)In addition, three Appendixes (online) with all the relevant mathematical proofs are attached to this paper. They are written in the Maxima language, and Maxima is a symbolic manipulator that may be downloaded for free from the web.In conclusion, this paper further increases the huge mathematical spectrum of applications of the Evo-SETI Theory to prepare Humans for the first Contact with an Extra-Terrestrial Civilization.


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