The Neandertal genome

Introduction

Recent advances in high-throughput DNA sequencing have provided initial glimpses of the nuclear genome of Neandertals as well as other ancient mammals including cave bears and mammoths. In the 7 May 2010 issue of Science, an international team of researchers presents the draft sequence of the Neandertal genome composed of over 3 billion nucleotides from three individuals.

Because Neandertals are much closer kin to us than are chimpanzees, which diverged from the human lineage 5 to 7 million years ago, matching Neandertal DNA against our own has the potential to reveal genetic changes that help define who we are.

About Neandertals

Neandertals (Homo neanderthalensis) are currently believed to be our closest evolutionary relatives. Although some researchers once thought they were our immediate ancestors in Europe, most now agree that Neandertals and modern humans most likely shared a common ancestor within the last 500,000 years, possibly in Africa.

The morphological features typical of Neandertals first appear in the European fossil record about 400,000 years ago, with bones of full-fledged Neandertals showing up at least 130,000 years ago. They lived in Europe and western Asia, as far east as southern Siberia and as far south as the Middle East (see map), before disappearing from the fossil record about 30,000 years ago.

Map showing range of Neandertal existence

At home in Eurasia. Neandertals ranged from Europe to southern Siberia.

Fossil remains and anatomical reconstructions indicate that the typical Neandertal had a stocky muscular body with short forearms and legs, a large head with bony brow ridges and a brain slightly larger than ours, a jutting face with a large nose, and perhaps reddish hair and fair skin. Neandertals made and used a diverse set of sophisticated tools, controlled fire, organized their living spaces, hunted and fed on game of various sizes, and occasionally made symbolic or ornamental objects.

For more Neandertal basics, see A Neandertal Primer by M. Balter, Science 323, 870 (2009).

Timeline of Discoveries

The first Neandertal fossils were discovered in 1829 in Engis, Belgium, and in 1848 at Forbes’ Quarry, Gibraltar, but were not recognized as an early human species until after the 1856 discovery of “Neandertal 1”– a 40,000-year-old specimen, including a skullcap and various bones, found at the Kleine Feldhofer Grotte in the Neander Valley near Düsseldorf, Germany.

This timeline highlights key discoveries about our closest relatives, from early fossil finds to the publication of the draft nuclear genome sequence.

1829 First Neandertal fossil found in Engis, Belgium, but not recognized as an extinct human.
 
18481829
Neandertal skull found at Forbes’ Quarry, Gibraltar; again not recognized as a prehistoric human.
 
1856 1,21856
First recognized early human fossil: A 40,000-year-old type specimen “Neandertal 1”, including a skullcap and various bones, discovered at the Kleine Feldhofer Grotte in the Neander Valley near Düsseldorf, Germany.
18643 Homo neanderthalensis becomes the first fossil hominin species to be named.
1886 Two nearly complete Neandertal skeletons (male and female) found with Stone Age tools in Spy, Belgium.
1908 Nearly complete Neandertal skeleton discovered at La Chapelle-aux-Saints in southern France.
 
19091909
Largest and most complete Neandertal skull discovered, along with several other Neandertal fossils, in the rock shelter of La Ferrassie in southwestern France.
 
1930–1932 Skeleton of female Neandertal excavated at Tabun Cave, Palestine (now Israel), the first confirmed discovery of Neandertals outside Europe.
 
1953–19571953
Several Neandertal skeletons discovered in Shanidar Cave in northern Iraq.
 
19794 Neandertal skeleton found at Saint-Césaire in western France, associated with sophisticated stone tools.
19835 Neandertal skeleton found at Kebara Cave, Israel.
1987–1991 New dating of Neandertal and modern human skeletons from Levant show modern humans from this region are older and cannot be descended from Neandertals
 
1997 61997
First Neandertal mitochondrial DNA sequenced (~400 bases)
2000 7 Second mtDNA analysis of a Neandertal
2006 8,9 Partial sequencing of Neandertal genomic DNA
2007 112007
Neandertals found to have red hair and fair skin
2007 12 Neandertals and modern humans share the same variant of the language gene FOXP2
2007 10 Neandertals roamed as far as Siberia
2008 13 Complete Neandertal mitochondrial genome sequenced
2008 14 Neandertals found with type O blood
2009 15 Retrieval and analysis of five Neandertal mtDNA genomes
2010 16 Perforated and painted shells indicate Neandertal symbolic behavior
2010 17 At least 3 subgroups of Neandertals lived in western Europe, southern Europe, and western Asia
2010 18 Draft sequence of the Neandertal genome

Timeline References

  1. – J. C. Fuhlrott, Verh. naturhist. Ver. preuss. Rheinl. 14, Corr. Bl., 50. (1857)
  2. – H. Schaaffhausen, Verh. naturhist. Ver. preuss. Rheinl. 14, Corr. Bl., 50–52. (1857)
  3. – W. King, Quarterly Review of Science 1, 88 (1864).
  4. – Lévêque and Vandermeersch, Bulletin de la Société Préhistorique Francaise 77, 35 (1980).
  5. – Rak and Arensburg, Am. J. Phys. Anthropol. 73, 227 (1987).
  6. – Krings et al., Cell 90, 19 (1997).
  7. – Ovchinnikov et al., Nature 404, 490 (2000).
  8. – Noonan et al., Science 314, 1113 (2006).
  9. – Green et al., Nature 444, 330 (2006).
  10. – Krause et al., Nature 449, 902 (2007).
  11. – Lalueza-Fox et al., Science 318, 1453 (2007).
  12. – Krause et al., Curr. Biology 17, 1908 (2007).
  13. – Green et al., Cell 134, 416 (2008).
  14. – Lalueza-Fox et al., BMC Evol. Biol. 8, 342 (2008).
  15. – Briggs et al., Science 325, 318 (2009)
  16. – Zilhao et al., Proc. Natl. Acad. Sci. U.S.A. 107, 1023 (2010).
  17. – Fabre et al., PLoS ONE 4, e5151. doi:10.1371/journal.pone.0005151 (2010).
  18. – Green et al., Science 328, 710 (2010).
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