Deadly drink decimated dinos

geosociety.org

Researchers think killer algae may have been partly to blame for major species die-offs in Earth's history. For each of the planet's five biggest mass extinctions – including when the dinosaurs became extinct – they have found a dramatic rise in the number of stromatolites – fossilized algae mats.

Sudden temperature changes or a large influx of sediments into waterways boosts algae growth. The population explosion also increases potentially toxic by-products produced by the algae, tainting plants and water that can sicken or kill creatures.