LIFE × EVOLUTION

Colonies That Act as One Animal

~200 to 100 million years ago

Phanerozoic · Mesozoic · Jurassic

Insects that give up reproducing to raise their siblings, in colonies that behave like a single body. It happened in termites first, then independently in ants, bees and wasps. Ants preserved in hundred-million-year-old amber already carry the antennal organs used to smell an alarm and to tell a nestmate from a stranger, two signals no colony can work without.

Why it matters

Sequencing their genomes shows how fast it was built. The three gene functions under the strongest selection as the main ant lineage appears are linked to caste differences, worker sterility and queen longevity, which is to say the very features complex eusociality rests on. The molecular foundations seem to have been laid in under twenty million years.

Dating & uncertainty

Termite eusociality is placed at around 200 million years ago by a family tree built on anatomy and calibrated with its own fossils, an age its authors offer as a possibility rather than a settled figure; ants appear later, and amber specimens of 100 million years ago already carry the antennal organs used for colony recognition.

Sources

1. Jouault et al. (2021), Systematic Entomology · Revising dating estimates and the antiquity of eusociality in termites
2. Romiguier et al. (2022), Current Biology · Ant phylogenomics reveals a natural selection hotspot preceding the origin of complex eusociality
3. Taniguchi et al. (2024), Science Advances · Sensory evidence for complex communication and advanced sociality in early ants

Earth history as one day

22:56:331 h 3 min before midnight

if Earth’s 4.54 billion years were compressed into a single day