Did All Life Really Come From One Ancestor?

Rob Stadler and the Conversations crew examine protein sequence space, experimental evolution, and orphan genes—genes with no clear evolutionary family history—to argue that universal common ancestry does not adequately explain many biological innovations. They evaluate proposed explanations including de novo gene birth, gene duplication, and horizontal gene transfer against a separate “forest of life” model. References, projects, tools, and websites mentioned: “Descent from a Common Ancestor Restricts Exploration of Protein Sequence Space” — Lada H. Isakova et al., PNAS, 2026 https://doi.org/10.1073/pnas.2532018123 “Phenotypic and Molecular Evolution Across 10,000 Generations” — Johnson et al., eLife, 2021 Real Science Radio https://kgov.com/real-science-radio --- If you’d like to support our work and help us create more content across all platforms, we’d be grateful for any contribution. 🙏 Learn how to give at jesusandscience.org/donate. God bless you! Donate: 💝 jesusandscience.org/donate Research Page: 🔬 jmtour.com Facebook: 📘 facebook.com/drjamestour Instagram: 📸 instagram.com/drjamestour X/Twitter: 🐦 x.com/drjamestour TikTok: 🎶 tiktok.com/@drjamestour YouTube: ▶️ ⁨@DrJamesTour⁩ Discord: 💬 https://discord.gg/zUgBMKjk2p 00:00 The case against universal common ancestry 03:05 What makes evidence high confidence 06:15 Yeast evolution stalls near the finish 09:35 Enzyme systems and hidden complexity 12:46 The limits of protein sequence space 16:07 A forest of proteins before LUCA 19:24 Why different proteins need separate origins 22:45 Protein folds and inaccessible pathways 26:02 What does de novo gene evolution mean? 29:11 Topoisomerase V: a unique orphan gene 32:29 Tardigrade genes behind survival powers 35:32 Orphan genes build jellyfish stingers 38:32 Essential orphan genes in fruit flies 41:57 Major transitions require many new genes 45:18 Prokaryotes and eukaryotes differ deeply 48:48 The universal genetic code dilemma 52:17 How the jellyfish harpoon stiffens 55:32 The BSC4 de novo gene case in yeast 58:37 Can noncoding DNA become a new gene? 61:54 Modeling the mutations needed for BSC4 65:04 Three categories of orphan genes 68:15 Testing evolution by gene duplication 71:28 Viruses and horizontal gene transfer 74:44 Can extreme proteins evolve by chance? 78:13 Weighing the forest-of-life model 81:31 Human differences and genetic limits 84:38 Final thoughts on creation and science