The greatest ice ages during Earth's history occurred in the Precambrian, particularly the Cryogenian period (around 720 to 635 million years ago), characterized by extensive glaciation that may have covered much of the planet. The most notable examples of the waterfall model, a linear project management approach, include traditional software development processes where requirements are gathered, design is completed, implementation occurs, and finally, testing and maintenance take place sequentially. This model is often criticized for its rigidity, as it does not easily accommodate changes once a phase is completed.
It was the Precambrian time period.
Precambrian
Precambrian
About 87%
The pre-Cambrian period which is a little over 630 million years ago. Before this era, there were no biota which leave a decent fossil impression - mainly soft-bodied forms. But see Ediacara in Wikipedia for more information.The earth by comparison is about 4.5 billion years since formation in roughly its present form. [So 630/4.5 000 ]
geologic time scale
precambrian time
The precambrian era lasted from roughly 4.57 Ga to 0.54 Ga before today, equalling about 88 % of Earth's history.
precambrian
Precambrian
Ores mined from shields...
it was the first waterfall