揽瓜阁做题小分队 第20天 （两栖动物）种群下降与灭绝

大月亮cyn

Day20 ADEDBC

svwma

记下,回头再看.

木柚籽

"P1: （提出观点） [ declines in amphibian populations < signs of extinctioon ] +opinions of environmentalists
P2: （评估观点）distinction between a declining population and extinction --> many factors lead to decline
P3: （承上）boilogists' opinion [ population declines>extinctions ] -->反驳P1观点
P5:  （总结）identifying real declines needs more data [ but we should pay attenntion in time] --> warning. "               

B及站士

P1.
1. Recent reports: of drastic declines in amphibian populations and of extinctions of a number of the world's endangered amphibian species
2. Environmentalists: immediate environmental action -> to remedy "amphibian crisis" – an indicator of environmental degradation due to human activity

P2.
1. Evaluation: A declining population ≠ endangered one
2. Elaborate: endangered one is always rare, small, and under constant threat of extinction even without a proximate cause in human activities – chance events may lead to its extinction (depends on the population size)

P3.
1. Biologists’ concern: population declines are more worrisome than extinctions – indicate a changed ecological context
2. Argument: distinctions must be made among apparent declines/ lower acceptable declines/ threaten extinction delcines
3. Difficulties: Anecdotal reports can’t distinguish + amphibian have shown fluctuations before

P4.
1. Evidence: long-term scientific data on amphibian populations is not enough
2. Example: many amphibian species extinct after severe declines in the 1950s and 1960s have subsequently recovered
3. Reminder: long-term data will not soon be forthcoming – postponing environmental action while we wait for it may doom species and whole ecosystems to extinction

joliajjj

文章结构：

P1：提出观点：两栖动物的数量和种类都在下降；环境学家指出是人类活动使其环境遭到破坏

P2：验证观点;存在漏洞  说明：物种下降与环境下降；说明原因
P3：生物学家认为数量下降比濒临灭绝更让人担忧，说明生态环境改变；下降分安全下降和威胁下降，在过去，am的数量强烈波动
P4：没有足够长期的数据说明真正下降的原因
ADEDB
1.allay 减轻的意思
2的C 没有说warranted，没有说是必要的
3物种下降而不是灭绝与环境下降关联，但下降还要分安全下降和威胁灭绝下降