[解析]
(1)推理判断题。根据第一段In southeastern Brazil,local fishers walk into dark waters in search of mullet On their own,it would be tricky to find the silvery fish.But the humans get help from an unusual partner:wild bottlenose dolphins.(在巴西东南部,当地渔民走进黑暗的水域寻找鲻鱼,独自一人要找到这种银色的鱼是很困难的。但人类得到了一个不寻常的伙伴的帮助:野生宽吻海豚。)以及第二段中A signal from the dolphins—usually a deep dive—indicates when they should cast their nets.This fishing partnership has passed down through the generations,lasting for more than a century.(海豚发出的信号﹣﹣﹣通常是深潜﹣﹣﹣表明它们应该在什么时候撒网。这种捕鱼伙伴关系世代相传,持续了一个多世纪。)可知,关于巴西渔民,前两段讲了他们在海豚的帮助下收获了更多的鱼。故选B项。
(2)细节理解题。根据第三段中Now,in a new study in Proceedings of the National Academy of Sciences,researchers suggest cetaceans that hunt with humans have more chances to live than those that don't.(现在,在《美国国家科学院院刊》上发表的一项新研究中,研究人员指出,与人类一起捕食的鲸类动物比那些不与人类一起捕食的鲸类动物有更多的生存机会。)可知,毛里西奥•康托的研究表明了与人类合作的海豚存活率更高。故选D项。
(3)词义猜测题。根据第五段中Fishers were more successful when they worked with the dolphins.(当渔民和海豚一起工作时,他们更成功。)以及Eighty﹣six percent of all 4.955 mullet caught during the study period came from "synchronous interactions(在研究期间捕获的4.955条鲻鱼中,86%来自"同步互动。)故可猜测,划线单词allies为"盟友,合作伙伴"的意思,结合选项C项Partners"伙伴,搭档"意思一致。A.Prey.猎物;B.Mullet.鲻鱼;C.Partners.伙伴;D.Researchers.研究人员。故选C项。
(4)目的意图题。根据文章大意以及第一段In southeastern Brazil,local fishers walk into dark waters in search of mullet On their own,it would be tricky to find the silvery fish.But the humans get help from an unusual partner:wild bottlenose dolphins.(在巴西东南部,当地渔民走进黑暗的水域寻找鲻鱼,独自一人要找到这种银色的鱼是很困难的。但人类得到了一个不寻常的伙伴的帮助:野生宽吻海豚。)以及最后一段The study also revealed dolphins hunting with humans had a 13 percent increase in survival rate over other dolphins.These cooperative dolphins are more likely to stay near the shore,reducing their chance of entanglement in illegal fishing equipment.Besides,the dolphins can take some fish directly from the fishers' harvest.(研究还显示,与人类一起捕猎的海豚比其他海豚的存活率提高了13%。这些合作的海豚更有可能呆在海岸附近,减少了被非法捕鱼设备缠住的机会。此外,海豚可以直接从渔民的收获中获得一些鱼。)可推知,作者写文章的主要目的是展示一种独特的人与海豚的关系。A.To appeal for the protection of sea creatures.呼吁保护海洋生物;B.To show a unique human﹣dolphin relationship.来展示人类和海豚的独特关系;C.To applaud for development in fishing research.为渔业研究的发展喝彩;D.To encourage fishers to better draw on dolphins.鼓励渔民更好地借鉴海豚。故选B项。