Unity of Life
🐝 Structural Unity of Life:
All life forms on the Earth are connected through their structure. We can refer to this as the structural unity of life. There are only a few elements that makeup all the different life forms on Earth. These elements include Carbon, Hydrogen, Oxygen, Nitrogen, Sulfur, Phosphorus, and some others. The fact that so many unique and seemingly unalike living things come from a handful of elements is remarkable.
These elements combine into chains to make molecules called amino acids, 20 of which are used by living organisms. These amino acids combine to form even more complex molecules called proteins which give living beings their structure, like the scales on a snake’s skin and hemoglobin in our blood, the horns of a rhino, and the wings of a butterfly.
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🦆Genetic Unity of Life:
All terrestrial organisms that replicate need to store genetic information and pass it on to their off-springs. This is done using molecules such as Deoxyribonucleic acid (DNA) or Ribonucleic acid (RNA). DNA consists of two strands of molecules looping around each other. When a cell replicates, the strands separate, and each strand makes a copy of the other strand. As a result, two DNA molecules are ready to be transferred to the daughter cells.
There could be mistakes made during the DNA copying process. These mistakes are called mutations. Mutations are prevalent, but most of them do not change how the genes express themselves. Different genotypes can still have the same phenotype. There are some mutations that do change how the genes express in a living being. These mistakes are what makes evolution possible. Good mutations are “encouraged” by nature and “bad” ones are discouraged through natural selection.
For example, a mutation that results in green color is helpful for small insects as they can hide in the greenery of trees which helps them avoid predators. The insects that stand out on a green background are wiped out because they cannot avoid predators. This is the process of natural selection. The first mutation continues through the generations and soon the only insects left are the ones who can blend in with their environment.
Mutations and Natural selection keep the wheel of evolution turning.
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🧬 Unity of Energy:
Sri Lankan scientist Cyril Ponnamperuma and American astronomer Carl Sagan created ATP in a Miller-Urey-type experiment (Arny and Schneider). Adenosine Triphosphate (ATP) is the molecule cells use to generate energy. ATP formation in Laboratory was another step toward understanding the unity of life.
The fact that all organisms use the same molecules (DNA or RNA) to pass on genetic information, use the same molecule for energy (ATP), and are made of the same handful of elements are exceptional affirmations for the unity of all life on our blue planet.
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[1] Arny and Schneider, Explorations: An Introduction to Astronomy.
