A potentially new species of hominid has been discovered based on the DNA from a 40,000 year old finger bone. The bone belonged to a 5-6 year old child and was found at the Denisova archaeological site, a southern Siberian cave, by Russian researchers in 2008. The finger bone yielded some mitochondrial DNA (maternally inherited, non-nuclear DNA) which is being used to identify evolutionary lineage. Neanderthal mtDNA differs from modern human (Homo sapiens) at 202 nucleotide positions on average; The new mtDNA differs at 385 positions on average. This suggests that this new specimen was unrelated to Neanderthals and also unrelated to modern humans- it diverged from these two species approximately 1 million years ago.
Also, the mtDNA suggests that this species of hominid coexisted with both humans and Neanderthals. In the future, the researchers are hoping to extract some chromosomal DNA to compare with that of humans and Neanderthals. Should this analysis find similar results it will be the first time that an extinct human relative has been identified using DNA.
This new hominid species appears to be closer related to humans than apes and to have walked upright. Along with the bones the scientists found bracelets and other decorations similar to those typically found with prehistoric humans. Although paleoanthropologists are applying caution in assigning these objects to this species.
Read many many more details in this Nature News article: http://www.nature.com/news/2010/100324/full/464472a.html
The report in USA: http://www.usatoday.com/tech/science/discoveries/2010-03-24-NEWSPECIES25_ST_N.htm
(image from evolution.berkeley.edu)