Size Plays a Role in Evolution; Small Organisms Have Advantage Over Big Counterparts

Tiny organisms have an advantage when it comes to evolution. According to experts, the size of small animals like insects allows them to live in great diversity.

The Smaller The Size, The Better in Evolution

From an evolutionary perspective, small truly does seem to be beautiful. Even though the greatest dinosaurs, pterosaurs, and mammals may appear formidable, minuscule bacteria, single-celled algae, and fungi significantly outnumber these enormous creatures. Furthermore, little creatures are ancient and extraordinarily robust.

Compared to their later, frequently enormous cousins, the first mammals and some of the earliest dinosaurs (such as the Eoraptor, less than two meters long) were likewise very small.

Because of their small size, animals may occupy a wider variety of niches and divide resources more precisely, allowing more species and individuals to coexist in the same ecosystem. Insects are experts at using this tactic.

The first signs of single-cell creatures were discovered about 3.8 billion years ago, just after the newly formed Earth had cooled enough for organic life to arise. Larger and more complex animals first appeared a little over half a billion years ago, after multicellular organisms emerged less than a billion years ago.

Most of Earth's history has been dominated by species no bigger than a human hair in diameter.

Although being small has advantages in evolution, there are also benefits to being big. Being larger may help an animal avoid predators. For instance, whales and elephants have few adversaries other than humans. A bigger size also allows them to hunt prey, outcompete competitors, and withstand short-term problems. Due to their lower surface area, larger organisms retain heat better and have higher intellectual potential.

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Short People Live Longer Than Tall Counterparts

Size also affects humans' longevity. According to one study, shorter people live longer than those who are taller than them. The researchers say shorter, smaller bodies have lower death rates and fewer diet-related chronic diseases, especially past middle age."

Among almost 2,500 male athletes from Finland, cross-country skiers were six inches shorter and typically lived nearly seven years longer than basketball players. Furthermore, men under five feet four inches lived two years longer than their taller counterparts in an Italian army research study.

An older study conducted in 1992 also reached the same conclusion. The study aimed to assess one component of the so-called entropy theory of aging, which postulates that an increase in internal disorder causes aging and predicts that a person's life expectancy decreases as mass increases.

Based on statistics for fewer groups of sportsmen and famous individuals in the USA, the first assessment of the relationship between human size and longevity or life span in 1978 revealed that shorter, lighter men live longer than their taller, heavier counterparts. A 1990 study that included 1679 men and women from the general American population validated these conclusions.