Wikipedia:Main Page history/2022 February 23b
From today's featured article.png) Reconstructed skull, with holotype elements in white Duriavenator is a genus of theropod dinosaur that lived in what is now England about 168 million years ago. Fossil jaw bones of a dinosaur (illustration pictured) collected near Sherborne, Dorset, in 1882 were considered by Richard Owen to belong to Megalosaurus bucklandii. It was recognised as a different species by 1964, moved to M. hesperis in 1974, and moved again to its own genus, Duriavenator 'Dorset hunter', in 2008. It was about 5 to 7 m (16 to 23 ft) long and weighed about 1 tonne (2,000 lb). The upper jaw's main bone is distinctive; its upper surface has a deep groove with numerous air-filled openings, and its lower has smaller foramina that connected with the upper jaw's front bone. It had about 4 teeth in the premaxilla, 14 to 16 in the rest of the upper jaw, and 14 to 15 in the lower jaw. The long lower front teeth may have been used for plucking and grasping food. Phylogenetic analyses have shown it to be among the oldest tetanuran theropods, and to belong in the family Megalosauridae. (Full article...)
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In the news.jpg) Mudslide in Petrópolis, Brazil
On this dayFebruary 23: The Emperor's Birthday in Japan (1960)  Raising the Flag on Iwo Jima
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The horse is a domesticated hoofed animal belonging to the subspecies Equus ferus caballus, part of the odd-toed ungulate order of mammals. Having been domesticated since at least 4000 to 3500 BC, horses now interact with humans in a wide variety of sporting competitions and non-competitive recreational pursuits, as well as in working activities such as police work, agriculture, entertainment, and therapy. Horses were historically used in warfare. This picture shows a diagram of the skeletal system of the horse, which has an average of 205 bones. A significant difference between the horse skeleton and that of a human is the lack of a collarbone – the horse's forelimbs are attached to the spinal column by a powerful set of muscles, tendons, and ligaments that attach the shoulder blade to the torso. The horse's leg bones are also proportioned differently from those of a human. The lower leg bones of a horse correspond to the bones of the human hand or foot. A horse has no muscles in its legs below the knees and hocks, only skin, hair, bone, tendons, ligaments, cartilage, and the assorted specialized tissues that make up the hoof. Diagram credit: Wilfredo Rodríguez
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