A couple of times in four billion years, evolution has slowed to a crawl. And an eon or so has passed before more complex life forms, such as simple animals, could arise. Evolution may have been ...

Research reveals when and why ancient tropical seas transitioned from oxygen oases to marine dead zones, providing clues to the long-term evolution of oceanic environments. The tropical oceans that ...

The Proterozoic Eon, spanning from 2,500 million to 539 million years ago, marked a transformative chapter in Earth's history ...

A study suggests that around 1 billion years ago, photosynthetic primary producers were likely too small to support the development of animal ecosystems. Approximately between 1.8 and 0.8 billion ...

The Proterozoic eon witnessed transformative shifts in Earth’s geochemical cycles, driven by evolving tectonic regimes, redox conditions and mantle processes. The assembly and dispersal of ...

Information-molecule loss from centriole-kinetosomes (such as gene loss in plastids and mitochondria) occurred in the sulphurous Proterozoic eon (2500–541 million years ago 17) during which time ...