课时作业8 Wildlife Protection-（课时作业）【红对勾讲与练】2024版新高考英语大一轮复习全新方案（人教版）

必修第二册　 3 课时作业 8　 WILDLIFE PROTECTION Ⅰ. 阅读理解 " (2022·辽宁省大连市考试) Endangered polar bears are breeding ( 繁殖) with grizzly bears ( 灰 熊 ), creating “ pizzly ” bears, which is being driven by climate change, scientists say. As the world warms and Arctic sea ice thins, starving polar bears are being forced ever further south, where they meet grizzlies, whose ranges are expanding northwards. And with that growing contact between the two come increasing hybrids (杂交种) . With characteristics that could give the hybrids an advantage in warming northern habitats, some scientists guess that they could be here to stay. “Usually, hybrids aren􀆳t better suited to their environments than their parents, but these hybrids are able to search for a broader range of food sources, ” Larisa DeSantis, an associate professor of biological sciences at Vanderbilt University, told Live Science. The rise of “pizzly” bears appears with polar bears􀆳 decline: their numbers are estimated to decrease by more than 30% in the next 30 years. This sudden fall is linked partly to “pizzly” bears taking up polar bears􀆳 ranges, where they outcompete them, but also to polar bears􀆳 highly specialized diets. “Polar bears mainly consumed soft foods even during the Medieval Warm Period, a previous period of rapid warming,” DeSantis said, referring to fat meals such as seals. “Although all of these starving polar bears are trying to find alternative food sources, like seabird eggs, it could be a tipping point for their survival. ” Actually, the calories they gain from