Three truths
- Timed
- Began about 2.7 billion years ago · the last 64% of life's story
- Named
- ≈1.7 million named living species · 99% of all named
- Weighed
- At least ≈464 Gt C · 84% or more of all life's carbon
- Part of Archaea (≈7 Gt C), not measured separately.
- Some members are not measured (no figure in Bar-On et al. 2018).
Archaea · group
Asgard archaea
Living · roughly 1.7 million described species
The date or placement of this group is still debated.
Archaea discovered mainly from environmental DNA, named after Norse realms. They carry genes once thought unique to complex cells, and genome studies place eukaryotes within this group.
Key characteristics
- Have proteins similar to those in complex cells
- Mostly known from DNA; very few grown in the lab
- Eukaryotes appear to branch from within them, near Heimdallarchaeia
- Habitat
- Marine sediments and other low-oxygen settings
- Branched off
- About 3.7 billion years ago (approximate)
- Parent lineage
- Archaea
Child lineages
Classification
Sources
- Zaremba-Niedzwiedzka et al. (2017). Asgard archaea illuminate the origin of eukaryotic cellular complexity · Nature
- Eme et al. (2023). Inference and reconstruction of the heimdallarchaeial ancestry of eukaryotes · Nature
- Asgard archaea (Wikipedia) · Wikipedia
- TimeTree: the timescale of life · TimeTree
- Open Tree of Life · Open Tree of Life
- Tree of Life Web Project · Tree of Life Web Project