Relatives of the trilobites, 它们是三叶虫的亲戚 their hard exoskeletons had served as useful armor underwater. 坚硬的外骨骼在水下是有用的护甲 On land, that armor supported them 在陆地上 这护甲支撑着它们 and prevented them from drying out. 并防止水分流失 They could also breathe throu...
The first animals to ever set foot on land were the arthropods. 率先踏上陆地的动物是节肢动物 Relatives of the trilobites, 它们是三叶虫的亲戚 their hard exoskeletons had served as useful armor underwater. 坚硬的外骨骼在水下是有用的护甲 On land, that armor supported them 在陆地上 这护甲...
their hard exoskeletons had served as useful armor underwater. 坚硬的外骨骼在水下是有用的护甲 On land, that armor supported them 在陆地上 这护甲支撑着它们 and prevented them from drying out. 并防止水分流失 They could also breathe through this tough exterior. 它们也可以通过这坚硬的外壳呼吸...
created new habitats for the next invaders from the sea. 为来自海洋的下一批入侵者 创造了新的栖息地 The first animals to ever set foot on land were the arthropods. 率先踏上陆地的动物是节肢动物 Relatives of the trilobites, 它们是三叶虫的亲戚 their hard exoskeletons had served as usefu...
the arrival of plants 植物的到来 created new habitats for the next invaders from the sea. 为来自海洋的下一批入侵者 创造了新的栖息地 The first animals to ever set foot on land were the arthropods. 率先踏上陆地的动物是节肢动物 Relatives of the trilobites, 它们是三叶虫的亲戚 their hard exos...
the most visible signs of life on our planet. 植物 是我们星球上的生命最鲜明的标志 Back in Earth's distant past, 在地球遥远的过去 the arrival of plants 植物的到来 created new habitats for the next invaders from the sea. 为来自海洋的下一批入侵者 创造了新的栖息地 The first animals to ever...
Back in Earth's distant past, 在地球遥远的过去 the arrival of plants 植物的到来 created new habitats for the next invaders from the sea. 为来自海洋的下一批入侵者 创造了新的栖息地 The first animals to ever set foot on land were the arthropods. 率先踏上陆地的动物是节肢动物 Relatives o...
they are the tallest living things to have ever existed. 是史上最高的生物 But redwoods are just one of more than 400,000 species of plant, 但是红杉只是40万植物物种中的一个 the most visible signs of life on our planet. 植物 是我们星球上的生命最鲜明的标志 Back in Earth's distan...
But redwoods are just one of more than 400,000 species of plant, 但是红杉只是40万植物物种中的一个 the most visible signs of life on our planet. 植物 是我们星球上的生命最鲜明的标志 Back in Earth's distant past, 在地球遥远的过去 the arrival of plants 植物的到来 created new habitats ...
they towered above the world around them. 从周围的世界中高耸出来 Today's redwoods are nature's skyscrapers. 今天的红杉是大自然的摩天大厦 Reaching heights of more than a hundred meters, 高度超过100米 they are the tallest living things to have ever existed. 是史上最高的...