From today's featured articleAcamptonectes is a genus of ophthalmosaurid ichthyosaurs, dolphin-like marine reptiles that lived during the Early Cretaceous around 130 million years ago. The first specimen—a partial adult skeleton—was discovered in Speeton, England, in 1958, but it was not formally described until 2012. Acamptonectes had unusual adaptations that made its trunk rigid, including tightly-fitting bones in the occiput (back and lower part of the skull) and interlocking vertebral centra, likely allowing it to swim at high speeds with a tuna-like form of locomotion. Other distinguishing characteristics include an extremely slender snout and unique ridges on the basioccipital bone of the braincase. As an ichthyosaur, Acamptonectes had large eye sockets and a tail fluke. Its teeth, which were slender and textured with longitudinal ridges, were probably adapted for impaling prey such as squid and fleshy fish. (Full article...)
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The siege of Osaka was a series of battles undertaken by the Japanese Tokugawa shogunate against the Toyotomi clan, and ending in the clan's dissolution. Divided into two stages (the winter campaign and the summer campaign), and lasting from 1614 to 1615, the siege put an end to the last major armed opposition to the shogunate's establishment. This eight-metre-long (26 ft) painting, titled The Summer Battle of Osaka Castle and executed on a Japanese folding screen, illustrates Osaka Castle under siege, and was commissioned by the daimyo Kuroda Nagamasa, who took a team of painters with him to the battlefield to record the event. The painting depicts 5071 people and 21 generals, and is held in the collection of Osaka Castle. Painting credit: unknown
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