Earth has been habitable for 4.3 billion years, and the earliest rock record indicates the
presence of a microbial biosphere by at least 3.4 billion years ago—and disputably earlier …

Astrobiology is the science that seeks to understand the story of life in our universe.
Astrobiology includes investigation of the conditions that are necessary for life to emerge …

Precise and accurate U–Pb LA–ICPMS dating of many U-bearing accessory minerals (eg
apatite, allanite, titanite and rutile) is often compromised by common Pb. LA–ICPMS dating …

We describe the history and features of the Ladder of Life Detection, a tool intended to guide
the design of investigations to detect microbial life within the practical constraints of robotic …

Construction and assembly of the Geologic Time Scale involves:(a) constructing a relative
(chronostratigraphic) standard scale for key periods in the Earth's rock record;(b) identifying …

“Natural selection can preserve innovations, but it cannot create them. Nature's many
innovations—some uncannily perfect—call for natural principles that accelerate life's ability …

Although it is widely believed that production of organic compounds by Fischer–Tropsch
synthesis and related processes occurs in many geologic environments, unambiguous …

A granodiorite from Akilia, southwest Greenland, previously suggested to date putative life-
bearing rocks to≥ 3· 84 Ga, is re-investigated using whole-rock major and trace-element …

The rock record provides us with unique evidence for testing models as to when and where
cellular life first appeared on Earth. Its study, however, requires caution. The biogenicity of …

Iron is a remarkable element in its relatively high abundance for its mass and its sensitivity to
(and control of) redox on a planetary scale over geologic time. Numerous volumes have …