page_title: Rotating locomotion in living systems
hierarchical_section_title: Rotating locomotion in living systems
caption_attribution_description: English: Artifact of East Mexico culture exhibited in the Ethnological Museum, Berlin, Germany. The artifact is in the public domain in Mexico: This work is in the public domain in Mexico because either its author died before 1952 (Mexico had a term of 30 years after the author's death until 1982, and no copyright term extension in 1982 or later restored copyright to expired works), or it is a work of the Mexican government and it was published more than 100 years ago (details). English&#160;| español&#160;| suomi&#160;| македонски&#160;| русский&#160;| +/−
context_page_description: Several organisms are capable of rolling locomotion. However, true wheels and propellers—despite their utility in human vehicles—do not appear to play a significant role in the movement of living things. Biologists have expounded on the reasons for this apparent absence of biological wheels, and wheeled creatures have appeared often in speculative fiction.
  Given the ubiquity of the wheel in human technology, and the existence of biological analogues of many other technologies, the lack of wheels in the natural world would seem to demand explanation—and the phenomenon is broadly explained by two main factors. First, there are several developmental and evolutionary obstacles to the advent of a wheel by natural selection, addressing the question "Why can't life evolve wheels?" Secondly, wheels are often at a competitive disadvantage when compared with other means of propulsion in natural environments, addressing the question "If wheels could evolve, why might they be rare nonetheless?" This environment-specific disadvantage also explains why at least one historical civilization abandoned the wheel as a mode of transport.
context_section_description: Several organisms are capable of rolling locomotion. However, true wheels and propellers—despite their utility in human vehicles—do not appear to play a significant role in the movement of living things (with the exception of certain flagella, which function like corkscrews). Biologists have expounded on the reasons for this apparent absence of biological wheels, and wheeled creatures have appeared often in speculative fiction.
  Given the ubiquity of the wheel in human technology, and the existence of biological analogues of many other technologies (such as wings and lenses), the lack of wheels in the natural world would seem to demand explanation—and the phenomenon is broadly explained by two main factors. First, there are several developmental and evolutionary obstacles to the advent of a wheel by natural selection, addressing the question "Why can't life evolve wheels?" Secondly, wheels are often at a competitive disadvantage when compared with other means of propulsion (such as walking, running, or slithering) in natural environments, addressing the question "If wheels could evolve, why might they be rare nonetheless?" This environment-specific disadvantage also explains why at least one historical civilization abandoned the wheel as a mode of transport.
caption: A toy animal with wheels, from Pre-Columbian Mexico[1]
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