A Revised Timescale for Human Evolution Based on Ancient Mitochondrial Genomes

• DOI: 10.1016/j.cub.2013.02.044
• Publication Date: 2013-03-21T13:29:08Z
• Authors: Qiaomei Fu; Alissa Mittnik; Philip L.F. Johnson; Kirsten Bos; Martina Lari; Ruth Bollongino; Chengkai Sun; Liane Giemsch; Ralf Schmitz; Joachim Burger; Anna Maria Ronchi...; Fabio Martini; Renata G. Cremonesi; Jiří Svoboda; Peter Bauer; David Caramelli; Sergi Castellano; David Reich; Svante Pääbo; Johannes Krause
• Keywords: 0301 basic medicine; Time Factors; Agricultural and Biological Sciences(all); Base Sequence; Models, Genetic; Biochemistry, Genetics and Molecular Biology(all); Fossils; Genome, Human; Molecular Sequence Data; High-Throughput Nucleotide Sequencing; ancient modern humans; mitochondrial genome; mitochondrial clock; Bayes Theorem; Evolution, Molecular; mitochondrial clock; 03 medical and health sciences; Haplotypes; mitochondrial genome; Genome, Mitochondrial; ancient modern human; Linear Models; Humans; ancient DNA Human Evolution; Phylogeny; Demography

Recent analyses of de novo DNA mutations in modern humans have suggested a nuclear substitution rate that is approximately half that of previous estimates based on fossil calibration. This result has led to suggestions that major events in human evolution occurred far earlier than previously thought.Here, we use mitochondrial genome sequences from ten securely dated ancient modern humans spanning 40,000 years as calibration points for the mitochondrial clock, thus yielding a direct estimate of the mitochondrial substitution rate. Our clock yields mitochondrial divergence times that are in agreement with earlier estimates based on calibration points derived from either fossils or archaeological material. In particular, our results imply a separation of non-Africans from the most closely related sub-Saharan African mitochondrial DNAs (haplogroup L3) that occurred less than 62-95 kya.Though single loci like mitochondrial DNA (mtDNA) can only provide biased estimates of population divergence times, they can provide valid upper bounds. Our results exclude most of the older dates for African and non-African population divergences recently suggested by de novo mutation rate estimates in the nuclear genome.