Liquid oxygen
TL;DR
Liquid oxygen - requires enrichment with adjacent possible narrative
Independently obtained by Louis Paul Cailletet in France and Raoul Pictet in Switzerland. Zygmunt Wróblewski and Karol Olszewski made more significant amounts in 1883 (see liquid nitrogen entry)
What Had To Exist First
Preceding Inventions
What This Enabled
Inventions that became possible because of Liquid oxygen:
Independent Emergence
Evidence of inevitability—this invention emerged independently in multiple locations:
Switzerland
Parallel development
Biological Patterns
Mechanisms that explain how this invention emerged and spread: