Humans Nearly Went Extinct 1.2M Years Ago

Hugh Pickens writes "Scientific American has a story on researchers from the University of Utah who have calculated that 1.2 million years ago, at a time when our ancestors Homo erectus, H. ergaster, and archaic H. sapiens were spreading through Africa, Europe, and Asia, there were probably only about 18,500 individuals capable of breeding in all these species together (PNAS paper here). Pre-humans were an endangered species with a smaller population than today's gorillas and chimpanzees. Researchers scanned two completely sequenced modern human genomes for a type of mobile element called Alu sequences, then compared the nucleotides in these old regions with the overall diversity in the two genomes to estimate differences in effective population size, and thus genetic diversity between modern and early humans. Human geneticist Lynn Jorde says that the diminished genetic diversity one million years ago suggests human ancestors experienced a catastrophic event at that time as devastating as the Toba super-volcano in Indonesia that triggered a nuclear winter and is thought to have nearly annihilated humans 70,000 years ago."

Comments

alternative: small population left africa

[peter303]

The TWO (only two) genomes analyzed were from the subpopulation which left Africa. If you fully sequence a native south African more genomic variety, this hypothesis may not hold up.

Humans Nearly Went Extinct 1.2M Years Ago

[3-State Bit]

Bah, you call that news? Try:
      "Humans Nearly Went Extinct 27 Years Ago"
the commander's Wikipedia entry says he:

"deviated from standard Soviet doctrine by correctly identifying a missile attack warning as a false alarm on September 26, 1983.[1] This decision most likely resulted in preventing an accidental retaliatory nuclear attack on the United States and its Western Allies."

You can follow any of the links in the above search, or here's a particularly lively read.