DENTON, Texas — Denton officials said a drop in oxygen killed fish in Unicorn Lake. Saturday, Denton's environmental services team assessed the dead fish at Unicorn Lake and determined the cause was ...

Residents of a town say a "total lack of care and maintenance" of a pond caused scores of fish to be washed up dead in the water. Moat Pond in East Grinstead, West Sussex, suffered an oxygen crash on ...

For now, complex life flourishes on our planet thanks to its supply of oxygen. But Earth's atmosphere wasn't always like it is today, and scientists predict that in the future, it will revert back to ...