Ratite Birds

Ratites - ostriches, emus, cassowaries, rheas, and kiwis - were long assumed to share flightlessness inherited from a common ancestor. Molecular evidence revealed the opposite: their ancestors were flying birds that colonized different continents, then each lineage independently evolved flightlessness. Continental drift separated populations that then converged on similar ground-dwelling strategies.

This demonstrates convergent evolution at continental scale. Different landmasses, separated by ocean barriers, independently produced large flightless birds from flying ancestors. The similar outcomes reflect similar selection pressures - large size and ground-dwelling lifestyle favored when predator pressures allowed flightlessness to evolve.

The business parallel applies to how similar market conditions produce similar companies in isolated regions. Each major economy developed its own search engine, social network, and e-commerce platform - often converging on similar features despite independent development. Like ratites evolving flightlessness separately, isolated markets produce convergent corporate forms because underlying selection pressures are similar.

Ratites also demonstrate the vulnerability of convergent giants. Each ratite lineage lost the flight capability that originally enabled colonization. They cannot re-evolve flight even when predators arrive. Companies that grow large by abandoning startup flexibility face similar constraints - they cannot rapidly recover capabilities shed during growth even when competitive conditions change.