Latest Proterozoic Stories
In devising his theories about evolution, Darwin theorized that species evolved on Earth slowly over millions of years. However, the fossil record doesn’t agree with the slow-and-steady model as a massive explosion of species took place 530 million years ago during the Cambrian era.
For those involved in and interested in the history of life and its evolution - including the inception of multicellular eukaryotes (organism with cells) - Virginia Tech released some very exciting news recently.
Geologists from Trinity College Dublin have rewritten the evolutionary history books by finding that oxygen-producing life forms were present on Earth some 3 billion years ago – a full 60 million years earlier than previously thought.
An unusual new fossil discovery of one of the earliest animals on earth may also provide the oldest evidence of muscle tissue – the bundles of cells that make movement in animals possible.
New three-dimensional reconstructions show how some of the earliest animals on Earth developed, and provide some answers as to why they went extinct.
UC Riverside research team challenges conventional view of a simple two-step rise in early oxygen on Earth; study suggests instead dynamic oxygen concentrations that rose and fell over billions of years
Stromatolites were the earliest visible manifestation of life on Earth. Now, a team of researchers suggest that the disappearance of stromatolites may have been driven by single-celled organisms called foraminifera.
About 635 million years ago, our world was covered in ice during an event called "Snowball Earth," and new details provide a new insight on the duration of this event.
The Neoproterozoic is the third of three subdivisions of the Proterozoic Eon (occurring from 1 billion years ago to 542 million years ago). This terminal era of the Proterozoic is itself divided into three sub-periods called the Tonian, Cryogenian, and Ediacaran Periods. The most severe glaciation known in the geologic record occurred during the Cryogenian Period, when ice sheets reached the equator and formed a possible “Snowball Earth.” And the earliest fossils of multi-cellular life...
The Paleoproterozoic is the first of three subdivisions of the Proterozoic Eon (occurring from 2.5 billion to 1.6 billion years ago (Ga). This period is marked by the first stabilization of the continents, and also when cyanobacteria--a type of bacteria that uses biochemical processes of photosynthesis to produce oxygen--evolved. Experts have found paleontological evidence that during at least part of the Paleoproterozoic era, about 1.8 Ga, the earth year was about 450 days long, with days...
The Archean (formerly Archaeozoic) is a geologic eon between the Hadean and Proterozoic eons. The Archean Eon begins at roughly 3.8 billion years ago (Ga) and ends at about 2.5 Ga. But unlike all other geological ages, which are based on stratigraphy, The Archean eon is defined chronometrically. The lower boundary of 3.8 Ga has also not been officially recognized by the International Commission on Stratigraphy. The name Archean is derived from the ancient Greek (Arkhe), meaning...
- A small wooded valley; a dell.
- The protecting weather-shed built around the entrance to a house.