/newsroom/taxonomy/term/10687/all en /newsroom/channels/news/billion-year-old-lake-deposit-yields-clues-earths-ancient-biosphere-288081 <p>A sample of ancient oxygen, teased out of a 1.4 billion-year-old evaporative lake deposit in Ontario, provides fresh evidence of what the Earth’s atmosphere and biosphere were like during the interval leading up to the emergence of animal life. </p> Tue, 17 Jul 2018 18:05:54 +0000 justin.dupuis@mcgill.ca 58963 at /newsroom