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A scanning electron microscope image of a cyanobacteria bloom in a body of water. The bacteria appear as small spherical cells each . AI generation.

Cyanobacteria begins to bloom on Lake Mendota, Lake Waubesa

Cyanobacteria bloom causes concern among UW partners, community officials

The Earth's gradually slowing rotation may have played a crucial role in the oxygenation of our atmosphere, a development essential for the emergence of complex life. Over billions of years, Earth's rotation has decelerated due to the Moon's gravitational pull, which causes tidal friction. This deceleration has lengthened Earth's days, from ~ 18 hours, 1.4 billion years ago, to the current 24 hours, with an ongoing increase of about 1.8 milliseconds per century. A 2021 study suggests that longer

Earth's rotation has been gradually slowing since its formation 4.5 billion years ago, leading to longer days over geological time. This deceleration is primarily due to the Moon's gravitational pull, which causes tidal friction that slows Earth's spin. For instance, 1.4 billion years ago, a day lasted only about 18 hours. This lengthening of days may have significantly influenced the oxygenation of Earth's atmosphere. Research suggests that longer days allowed photosynthetic organisms, such as