The Snowball Earth is a geohistorical hypothesis that proposes during one or more of Earth's icehouse climates, the planet's surface became entirely or nearly entirely frozen with no liquid oceanic or surface water exposed to the atmosphere. The most academically referred period of such global glaciation is believed to have occurred sometime before 650 mya during the Cryogenian period.
Artist's rendition of a fully-frozen Snowball Earth with no remaining liquid surface water.
Diamictite of the Neoproterozoic Pocatello Formation, a "snowball Earth"-type deposit
Elatina Fm diamictite below Ediacaran GSSP site in the Flinders Ranges NP, South Australia. A$1 coin for scale.
2.1 billion-year-old rock with black-band ironstone
A multicellular organism is an organism that consists of more than one cell, in contrast to unicellular organism. All species of animals, land plants and most fungi are multicellular, as are many algae, whereas a few organisms are partially uni- and partially multicellular, like slime molds and social amoebae such as the genus Dictyostelium.
The nematode Caenorhabditis elegans stained to highlight the nuclei of its cells