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Wheeled toy animal
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. (Full article...) Recently featured:
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Interior of the Duwamish Longhouse
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Mohammad bin Salman
On this day...November 6: Constitution Day in the Dominican Republic (1844); Gustavus Adolphus Day in Estonia, Finland and Sweden (1632); Finnish Swedish Heritage Day in Finland 
Portrait of George Eliot by François D'Albert Durade
Edmund Mortimer, 5th Earl of March (b. 1391) · James Bowdoin (d. 1790) · Jerry Yang (b. 1968) More anniversaries:
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Queen Victoria appointed 19 Knights Grand Cross of the Royal Victorian Order, plus an additional 28 honorary Knights Grand Cross, between the order's institution and her death on 22 January 1901. The Royal Victorian Order is an order of knighthood awarded by the sovereign of the United Kingdom and several Commonwealth realms. It is granted personally by the monarch and recognises personal service to the monarchy, the Royal Household, royal family members, and the organisation of important royal events. It was instituted with five grades, Knight Grand Cross, Knight Commander, Commander, Member (fourth class) and Member (fifth class). The two highest conferred the status of knighthood on holders. The first two appointments were to Queen Victoria's sons, Albert, Prince of Wales, and Prince Arthur, Duke of Connaught and Strathearn, who both received the highest grade on 6 May 1896. Of Queen Victoria's 19 Knights Grand Cross appointments, 6 were to Princes of the United Kingdom—her own children, grandchildren or other close relatives—and a further 7 to those already holding a peerage. (Full list...)
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The Raising of Lazarus is an oil painting on panel by the Dutch artist Rembrandt from early in his career. It was probably painted in the late 1620s or early 1630s. The work depicts the Raising of Lazarus as told in the Gospel of John, Chapter 11. It is in the collection of the Los Angeles County Museum of Art. Painting: Rembrandt Recently featured:
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