inget mellanstadium mellan aporna och människorna?

Så måste det väl finnas något, varför utvecklas inte aporna nudå?

In 1997, a segment of the hypervariable control region of the maternally inherited mitochondrial DNA (mtDNA) of the Neanderthal type specimen found at Feldhofer was sequenced. Phylogenetic analysis showed that it falls outside the variation of contemporary humans and shares a common ancestor with mtDNAs of present-day humans approximately half a million years ago5, 6. Subsequently, mtDNA sequences have been retrieved from eleven additional Neanderthal specimens: Feldhofer 2 in Germany7, Mezmaiskaya in Russia8, Vindija 75, 77 and 80 in Croatia9, 10, Engis 2 in Belgium, La Chapelle-aux-Saints and Rochers de Villeneuve in France10, Scladina in Belgium11, Monte Lessini in Italy12, and El Sidron 441 in Spain13. Although some of these sequences are extremely short, they are all more closely related to one another than to modern human mtDNAs9, 11.

This fact, in conjunction with the absence of any related mtDNA sequences in currently living humans or in a small number of early modern human fossils5, 10 strongly suggests that Neanderthals contributed no mtDNA to present-day humans. On the basis of various population models, it has been estimated that a maximal overall genetic contribution of Neanderthals to the contemporary human gene pool is between 25% and 0.1% (refs 10, 14). Because the latter conclusions are based on mtDNA, a single maternally inherited locus, they are limited in their ability to detect a Neanderthal contribution to the current human gene pool both by the vagaries of genetic drift and by the possibility of a sex bias in reproduction. However, both morphological evidence4, 15 and the variation in the modern human gene pool16 support the conclusion that if any genetic contribution of Neanderthals to modern human occurred, it was of limited magnitude.