Time flows from root to tip, past to present. The root grounds the common ancestor of every member of the tree and each node represents the most recent common ancestor of the lineages branching off.

Scientists know that the most recent common ancestor of cyanobacteria emerged about 3 billion years ago. It evolved into the current ecosystem through the Great Oxidation event, ...

The most recent common ancestor (MRCA) in the female line is determined by examining the Mitochondria of living females to estimate how many mutations would have to have taken place to account for ...

Timing is everything. Tracing the lineages of agricultural ants to their most recent common ancestor revealed that the ancestor probably lived through the end-Cretaceous mass extinction—the one ...

The last universal common ancestor is the single life form that branched into everything since. Earth four billion years ago may help us check for life on one of Saturn’s moons today.

The 3.2-million-year-old human ancestor known as Lucy rose to fame ... only evolved once in a recent common ancestor of the ... rather than jointly inheriting it from a common ancestor.

A new study suggests the platypus and echidna — the only egg-laying mammals — had a water-dwelling ancestor. The finding could upend what’s known of their evolution.