Life and the Universe

Life and the Universe

 Here is a synopsis of our discussion on Origin of Life and the Universe conducted on 21 October 2018.

 
A scientific theory is an explanation of an aspect of the natural world that can be repeatedly tested and verified in accordance with scientific method, using accepted protocols of observation, measurement, and evaluation of results. Science does not claim to have such a theory (an explanation) for the origin of life. However science today believes that all life on earth began as a result of the interaction of the chemicals and heat (from radiation, lightning, volcanic activity) present on the surface and in the atmosphere of the early earth. Life may have originated similarly on other planets in our Milky Way and in the entire universe.

After the initial Big Bang 13.8 billion years ago, gases present in the immense vastness of space condensed to form stars. The process of formation of stars and their death – all of creation and destruction - is an ongoing process. (New stars for example, are being formed in the region of the Orion’s Belt (Images are available on the website of NASA, Hubble Telescope). The earth was formed about 4.54 billion years ago along with our star, the sun. The Miller-Urey experiment (University of Chicago, 1953) showed that amino acids and lipids, which are building blocks of life, could be formed through a chemical reaction of ammonia, carbon, nitrogen, water vapour and electrical sparks. The scientific community believes that life originated as a result of natural chemical processes.

Fossils found in rock sediments (stromatolites), suggest the presence of microbes (cyanobacteria) as old as 3.7 billion years. The age of fossils and rocks are determined using radiometric dating (this measures the radioactive decay of an element), which has replaced the less accurate carbon dating. The oldest accepted fossils are those from Strelley Pool in the Pilbara region of Western Australia. They are stromatolites: preserved mats of microorganisms sandwiched between layers of sediment. These fossils are 3.4 billion years old. It is believed that early living beings such as trilobites came into existence in formations of clay.

The story of Genesis could be a symbol of the evolution of man and woman from layers of clay. Science does not speculate or use symbolic language. While it acknowledges that science cannot prove the origin of life, the evolution that followed the initial spark of life is evident and commonly accepted. Today evolution is validated through fossil records, embryology and DNA comparison. (The theory of evolution is not accepted by creationists, who believe in intelligent design. According to them and to people who take the Bible literally, the earth is around ten thousand years old.)

Evolution is an ongoing process by which hereditary information of one species is passed on to successive generations. This coded information is contained in the DNA of every living being. Through the recombination of DNA, through mutation (changes in DNA caused by environmental factors) and through natural selection, life forms and new species evolve continuously.
 
‘On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life’, published on 24 November 1859, is a work of scientific literature by Charles Darwin which is considered to be the foundation of evolutionary biology. Darwin's book introduced the scientific theory that populations evolve over the course of generations through a process of natural selection. It presented a body of evidence that the diversity of life arose by common descent through a branching pattern of evolution.

The scientific community believes that: 1- all living organisms are unique. 2- that all living organisms are related. 3 – that all living beings have a common ancestor (LUCA, Last Universal Common Ancestor).
 
Mathew Kuzhippallil

Switzerland, 21.October 2018
 
PS: Please see One Zoom Tree of Life Explorer (developed by scientists of the Imperial College London) on the internet for a better understanding of the process of evolution.