Three truths
- Timed
- Began about 750 million years ago · the last 18% of life's story
- Named
- ≈1.3 million named living species · 77% of all named
- Weighed
- ≈2 Gt C · 0.4% of all life's carbon
Eukaryotes · animals · kingdom
Animals
Animalia (Metazoa)
Living · roughly 1.3 million described species
The date or placement of this group is still debated.
Many-celled organisms that eat other organisms and, in most cases, move at some stage of life. Their closest single-celled relatives are the choanoflagellates.
Key characteristics
- Many cells without cell walls
- Most develop from a hollow ball of cells
- Most have muscles and nerves
- Branched off
- About 1.1 billion years ago (approximate)
- Parent lineage
- Holozoa
Child lineages
Classification
Sources
- Animal (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