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雷兽是奇蹄目中早已灭绝的一类。它的四肢和獏的有些接近,也是前肢四蹄、后肢三蹄。最早的代表只有羊那么大,后期体躯庞大笨重,头顶或鼻尖长着形状不一的骨质的角,有的角竟和头骨本身长度差不多,样子颇有些古怪。这类动物由于进化速度快,化石又特别多,是北美和亚洲老第三纪中有名的标准化石。它为什么有这样一个怪名字?人们是怎样逐渐认识它们的?它在古脊椎动物学的发展中曾起过什么样的作用?本文想侧重这几方面作些介绍。
Thunder beast is a long ago in the class of Extinct. Some of its limbs and fawn close, but also the forelimb four hooves, hind legs three hoofs. The earliest representatives of only the sheep so large, the latter part of the body bulky, head or tip of the nose with varying shapes of bone angle, and some actually the length of the skull itself is almost, look quite quirky. Due to the rapid evolution of these animals, fossils and particularly large, is the famous North American and Asian Tertiary standard fossils. Why does it have such a weird name? How do people gradually recognize them? What role does it play in the development of paleo-vertebrate zoology? This article would like to focus on these aspects.