کاربر:Sunfyre/فهرست نهنگها
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آببازسانان is an راسته (زیستشناسی) that comprises the 94 species of نهنگs, دلفینs, and گرازماهیs. It is divided into آببازسانیان دنداندارs (Odontoceti) and آببازسانیان بیدندانs (Mysticeti), which diverged from each other in the ائوسن some 50 million years ago (mya). Cetaceans are descended from land-dwelling hoofed mammals, and the now extinct کهنآببازسانانs represent the several transitional phases from terrestrial to completely aquatic.[1] Historically, cetaceans were thought to have descended from the wolf-like میانپنجهسانانs, but شاخهبندی analyses confirm their placement with جفتسمسانانs in the order Cetartiodactyla.[2][3][4][5][6]
Whale populations were drastically reduced in the 20th century from intensive شکار نهنگ, and the activity was globally banned in 1982.[7] Smaller cetaceans are at risk of accidentally getting caught by fishing vessels using, namely, ماهیگیری با تور ایستاده, drift netting, or صید گوشگیرting operations.[8] الگو:Mammals by population sidebar