Just recently, some scientists managed to sequence neanderthal dna. While this discovery is not totally explored at this point, the following data are quite solid.
Using different techniques, two teams of scientists separately sequenced large chunks of DNA extracted from the femur of a 38,000-year-old Neanderthal specimen found in a cave [image] 26 years ago in Croatia. One team sequenced more than one million base pairs and the other 65,000 pairs of the genome.
No evidence of interbreeding
The results from the new studies confirm the Neanderthal's humanity, and show that their genomes and ours are more than 99.5 percent identical, differing by only about 3 million bases.
In popular imagination, Neanderthals are often portrayed as prehistoric brutes who became outsmarted by a more advanced species, humans, emerging from Africa. But excavations and anatomical studies have shown Neanderthals used tools, wore jewelery, buried their dead, cared for their sick, and possibly sang or even spoke in much the same way that we do. Even more humbling, perhaps, their brains were slightly larger than ours.
The findings also appear to refute speculations by some scientists that Neanderthals and humans interbred in more recent times. "We see no evidence of mixing 30,000 to 40,000 years ago in Europe," Rubin said. "We don't exclude it, but from the data that we have, we have no evidence that pages were ripped from one genome and put in the other."
http://www.livescience.com/humanbiology/061115_neanderthal_dna.html
No interbreading satisfies the wt defintion of different kinds. It strongly suggests that they were a different species from us cro magnons. This discovery is another pillar in support of the biological evolutionary process.
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