The human genetic code was being worked on at a rapid pace in the 1990's. Fresh samples of pristine DNA were used to support that claim.
The old, degraded and contaminated genetic material from our ancestors was what Prof Paabo was interested in. It was thought to be difficult. He was the first person to sequence DNA from a 40,000-year-old bone.
Neanderthals were different from modern day humans and Chimpanzees.
He focused on hominins, a group of modern humans that also include our extinct relatives.
His discoveries give the basis for exploring what makes us uniquely human, the committee said.
Neanderthal and humans from around the world were compared with each other and it was found to be a close match.
The migration out of Africa around 70,000 years ago gave rise to sex and children with Neanderthals.
The legacy of that can still be seen. Our body's ability to respond to infections is affected by the amount of modern human DNA that comes from Neanderthals.
In 2008, the next major contribution to human origins was made. A 40,000-year-old finger bone was discovered in the Denisova cave.
Prof Paabo was able to sequence a sample of DNA and it turned out to be a previously unknown hominin.
Denisovans were a part of the genetic makeup of Homo sapiens. People in parts of South East Asia have a small amount of Denisovan in their genes.
Tibetans have a genetic inheritance that helps the body cope with low levels of oxygen and high altitudes.
Prof Paabo only found out about the news this morning when he got a call.
He was speechless. "I'm very happy," said Prof. Perlmann.
One of the founding fathers of paleogenomics is Prof Paabo. The 10m Swedish kronor is $800,000. His father won the same prize in 1982.
The work shows there were two distinct groups of hominins living in the same place.
The analysis suggests that the extinct populations may not have been able to compete with modern humans.