Quote by Charles Darwin
A grain in the balance will determine which individual shall live and which shall die - which variety or species shall increase in number, and which shall decrease, or finally become extinct.
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Summary
This quote highlights the significant impact that even the smallest factors can have on the survival and evolution of a species. It underscores the delicate balance of nature, wherein a slight change or advantage can determine the fate of individuals, populations, and even entire species. It emphasizes the importance of adaptation, competition, and natural selection, as even a grain of advantage can tip the scales towards the persistence or extinction of life forms.