The Senegal bichir represents an early branch of ray-finned fish, preserving traits that trace back nearly 380 million years.
Prokaryotes are nucleus-free cells that include both bacteria and archaea — the two lineages that split shortly after LUCA.
Archaea are a primary branch of early life, and eukaryotes emerged from within this archaeal lineage.
A lineage can survive for hundreds of millions of years while remaining morphologically recognizable. Living fossil is poetic, but scientifically the ginkgo represents a relict lineage and a morphologically conservative lineage.
Survival belongs to organisms that respond effectively to change as environments shift over time.