根据考古研究(英语:Archaeology of the Americas)及遗传学分析(英语:Genetic history of indigenous peoples of the Americas),至少在24,500年前育空北部即有人类活动,而南安大略的人类活动可以追溯到公元前7,500年。旧克罗平地(英语:Old
to natural forces or human activity, there is now substantial evidence to indicate that human activity – and specifically increased greenhouse gas (GHGs)
[2017-08-03]. (原始内容 (PDF)存档于2017-06-04). The Dutch curse: how billions from naturalgas went up in smoke 互联网档案馆的存檔,存档日期2016-12-21. LEES MEER, 17 June 2009 Global