Rotating locomotion in living systems – the use of wheels and
propellers by organisms – has long been pondered among biologists and
writers of speculative fiction. Rolling and wheeled creatures have
appeared in the legends of many cultures. While other human
technologies, like wings and lenses, have common analogues in the
natural world, and several species are able to roll, structures that
propel by rotating relative to a fixed body are represented only by the
corkscrew-like bacterial flagella. Macroscopic organisms have apparently
never evolved wheels, and this is attributed to two main factors:
limitations of evolutionary and developmental biology, and disadvantages
of wheels, when compared with limbs, in many natural environments.
Wheels, beyond the molecular scale, may not be within the reach of
natural evolution, and may be infeasible to grow and maintain with
biological processes. Compared with limbs, they are often less energy-
efficient, less versatile, and less capable of traversing or avoiding
obstacles. These environment-specific disadvantages of wheels also
explain why some historical civilizations abandoned them.
Read more: <https://en.wikipedia.org/wiki/Rotating_locomotion_in_living_systems>
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Today's selected anniversaries:
447:
A powerful earthquake destroyed large portions of the Walls of
Constantinople, including 57 towers.
<https://en.wikipedia.org/wiki/Walls_of_Constantinople>
1856:
Scenes of Clerical Life, the first work by English author
George Eliot, was submitted for publication.
<https://en.wikipedia.org/wiki/Scenes_of_Clerical_Life>
1935:
The Hawker Hurricane, the aircraft responsible for 60% of the
Royal Air Force's air victories in the Battle of Britain, made its first
flight.
<https://en.wikipedia.org/wiki/Hawker_Hurricane>
1977:
The Kelly Barnes Dam in Stephens County, Georgia, U.S.,
collapsed, and the resulting flood killed 39 people and caused $2.8
million in damages.
<https://en.wikipedia.org/wiki/Kelly_Barnes_Dam>
1995:
Madagascar's Rova of Antananarivo, which served as the royal
palace from the 17th to 19th centuries, was destroyed by fire.
<https://en.wikipedia.org/wiki/Rova_of_Antananarivo>
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Wiktionary's word of the day:
Bolshevism:
1. The strategy used by the Bolsheviks in attempting to gain power in
Russia.
2. The Communist totalitarian political ideology adopted by the Russian
Soviet Federative Socialist Republic and the Union of Soviet Socialist
Republics; Marxism-Leninism.
<https://en.wiktionary.org/wiki/Bolshevism>
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Wikiquote quote of the day:
Where words prevail not, violence prevails; But gold doth more
than either of them both.
--Thomas Kyd
<https://en.wikiquote.org/wiki/Thomas_Kyd>
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