Why Giant Prehistoric Animals Got Smaller

This is because the ratio of muscle strength to its cross-sectional area, or surface area of the muscle, is halved. No matter the size of the fly, its jumping ability will be limited.

Although the size of the animal depends on some basic factors, there is some flexibility. An animal can be much larger or smaller than another animal of the same species within a few kilometers. This is sometimes referred to as the "island rule" as the larger animals get smaller on the islands and the smaller ones get bigger.

Small animals (lower in the food chain) can be released onto islands if there are no natural predators and they are competing with their continental counterparts. While large animals, limited by lack of food, become smaller.

The Gargano Peninsula, which forms the backbone behind the boot of Italy, provides many examples in the fossil record. From the late Miocene to the early Pliocene (about 5.3 million years ago), when the level of the Mediterranean Sea was high, Gargano was isolated from mainland Italy and the island was covered with megafauna.

Hairy hedgehogs (also known as moon urchins) outpace their mainland counterparts. One species, Denogalerix koenigswaldi , had a 20-centimetre-long skull. There were also giant hamsters ( Hatomys gargantua ), giant otters ( Paralutra garganensis), and giant owls ( Tyto gigantea, larger than today's species).

Elsewhere, the human species, Homo floresiensis, is considered a possible case of insular dwarfism. The first specimen of H. floresiensis , nicknamed "The Hobbit" because of its small size, was found on the island of Flores and is believed to be 95,000 years old. One theory is that H. floresiensis is a descendant of dwarf Homo sapiens, or perhaps it is a dwarf of Homo erectus , and although their origin is unclear, these little guys seem to have thrived on their own on this island for thousands of years.

But the evidence for the "island rule" is mixed (the biologist who first proposed it suggested that there are more examples of the rule than exceptions, but he didn't say it always applied). While this is a good idea, it may turn out that animals are more flexible in how they reproduce than you might think.

Just look at people. The highest country, the Netherlands, averages 184 cm (6 ft) for men and 170 cm (5 ft 7 in) for women, while the lowest country, Timor-Leste, averages 160 cm (5 ft 3 in) for men and 153 cm (5 ft 3 in) for men. (5 feet) for women. . Nutrition and environment play a role in increasing the average height of the Dutch by 20 cm over the past two centuries, but sexual selection also plays a role. Being tall in the Netherlands is more attractive, so the Dutch get taller. ( Read more about why the Dutch are the tallest people in the world at BBC Riley .)

Our H. floresiensis cousins , who were shorter at 106 cm (3 ft 5 in), were the result of island rule, in short, because there was less food. Or it may be very small because being small is attractive. both of them.

Although a person's size can vary with human height, let's be grateful to biology and physics for keeping things under control. The chaotic world that Lyons and Cockerell showed us may seem very chaotic to me.

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