The Denisovans or Denisova hominins ( // di-NEE-sə-və) are an extinct species or subspecies of archaic humans in the genus Homo. Pending its status as either species or subspecies, it currently carries the temporary names Homo sapiens denisova, Homo sp. Altai, and Homo sapiens subsp. Denisova. In March 2010, scientists announced the discovery of a finger bone fragment of a juvenile female who lived about 41,000 years ago, found in the Denisova Cave in the Altai Mountains in Siberia, a cave that has also been inhabited by Neanderthals and modern humans. The mitochondrial DNA (mtDNA) of the finger bone showed it to be genetically distinct from Neanderthals and modern humans. The nuclear genome from this specimen suggested that Denisovans shared a common origin with Neanderthals, that they ranged from Siberia to Southeast Asia, and that they lived among and interbred with the ancestors of some modern humans, with about 3% to 5% of the DNA of Melanesians and Aboriginal Australians and around 6% in Papuans deriving from Denisovans.
A 2013 comparison with the genome of another Neanderthal from the Denisova cave revealed local interbreeding with local Neanderthal DNA representing 17% of the Denisovan genome, and evidence of interbreeding with an as yet unidentified ancient human lineage. Analysis of DNA from two teeth found in layers different from the finger bone revealed an unexpected degree of mtDNA divergence among Denisovans. Two teeth belonging to different members of the Denisova cave population have been reported. In November 2015, a tooth fossil containing DNA was reported to have been found and studied.
The Denisova Cave is in south-western Siberia, in the Altai Mountains near the border with China and Mongolia. It is named after Denis, a Russian hermit who lived there in the 18th century. The cave was originally explored in the 1970s by Russian paleontologist Nikolai Ovodov, who was looking for remains of canids. In 2008, Michael Shunkov from the Russian Academy of Sciences and other Russian archaeologists from the Institute of Archaeology and Ethnology of Novosibirsk investigated the cave. They found the finger bone of a juvenile hominin, known as both the "X woman" (referring to the maternal descent of mtDNA), and the Denisova hominin. Artifacts (including a bracelet) excavated in the cave at the same level were dated using radiocarbon and oxygen isotopes to around 40,000 BP. Excavations have since revealed human artifacts showing an intermittent presence going back 125,000 years.
A team of scientists led by Johannes Krause and Svante Pääbo from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, sequenced mtDNA extracted from the fragment. The cool climate of the Denisova Cave preserved the DNA. The average annual temperature of the cave is 0 °C, which has contributed to the preservation of archaic DNA among the remains discovered. The analysis indicated that modern humans, Neanderthals, and the Denisova hominin last shared a common ancestor around 1 million years ago.
The mtDNA analysis further suggested that this new hominin species was the result of an earlier migration out of Africa, distinct from the later out-of-Africa migrations associated with modern humans, but also distinct from the even earlier African exodus of Homo erectus. Pääbo noted that the existence of this distant branch creates a much more complex picture of humankind during the Late Pleistocene. This work shows that the Denisovans were actually a sister group to the Neanderthals, branching off from the human lineage 600,000 up to 744,000 years ago, and diverging from Neanderthals, probably in the Middle East, 200,000 years later.
Later in 2010, a second paper from the Svante Pääbo group reported the prior discovery, in 2000, of a third upper molar from a young adult, dating from about the same time (the finger was from level 11 in the cave sequence, the tooth from level 11.1). The tooth differed in several aspects from those of Neanderthals, while having archaic characteristics similar to the teeth of Homo erectus. They performed mtDNA analysis on the tooth and found it to have a sequence somewhat similar to that of the finger bone, indicating a divergence time about 7,500 years before, and suggesting that it belonged to a different individual from the same population.
So far, the fossils of four distinct Denisovans from Denisova Cave have been identified through their DNA: Denisova 2, Denisova 3, Denisova 4, and Denisova 8. Analysis of a fifth specimen, Denisova 11, proved it to have belonged to an F1 Denisovan-Neanderthal hybrid. Denisova 2 and Denisova 3 are prepubescent or adolescent females, while Denisova 4 and Denisova 8 are adult males. mtDNA analysis of the Denisovan individuals suggests the Denisova 2 fossil is the oldest, followed by Denisova 8, while Denisova 3 and Denisova 4 are roughly contemporaneous.
|Name||Species||Age||Discovery||Place||First Public||Image||Conservation||GenBank Accession|
(aka X Woman)
|Homo sp.||30–50 ka||2008
|Denisova cave (Russia)||Johannes Krause, et al.||Destroyed to investigate the mtDNA.||NC013993|
|Denisova 4 (molar)||Homo sp.||30–50 ka||2000||Denisova cave (Russia)||David Reich, et al.||FR695060|
|Denisova 8 (molar)||Homo sp.||2010||Denisova cave (Russia)||Susanna Sawyer, et al.||KT780370|
|Denisova 2 (molar)||Homo sp.||>100 ka||1984||Denisova cave (Russia)||Viviane Slon, et al.||KX663333|
(arm or leg bone fragment)
|~90 ka||2012||Denisova cave (Russia)||Samantha Brown, et al.||KU131206|
Little is known of the precise anatomical features of the Denisovans, since the only physical remains discovered thus far are the finger bone, two teeth from which genetic material has been gathered, and a toe bone. The single finger bone is unusually broad and robust, well outside the variation seen in modern people. It belonged to a female, indicating that the Denisovans were extremely robust, perhaps similar in build to the Neanderthals. The tooth does not share the derived morphological features seen in Neanderthal or modern human teeth. An initial morphological characterization of the toe bone led to the suggestion that it may have belonged to a Neanderthal-Denisovan hybrid individual, although a critic suggested that the morphology was inconclusive. This toe bone's DNA was analyzed by Pääbo. After looking at the full genome, Pääbo and others confirmed that humans produced hybrids with Denisovans.
Some older findings may or may not belong to the Denisovan line. These include the skulls from Dali and Maba, and a number of more fragmentary remains from Asia. Asia is not well mapped with regard to human evolution, and the above finds may represent a group of "Asian Neanderthals".
Mitochondrial DNA analysis
The mitochondrial DNA (mtDNA) from the finger bone differs from that of modern humans by 385 bases (nucleotides) out of approximately 16,500, whereas the difference between modern humans and Neanderthals is around 202 bases. In contrast, the difference between chimpanzees and modern humans is approximately 1,462 mtDNA base pairs. This suggested a divergence time around one million years ago. The mtDNA from a tooth bore a high similarity to that of the finger bone, indicating that they belonged to the same population. From a second tooth, an mtDNA sequence was recovered that showed an unexpectedly large number of genetic differences compared to that found in the other tooth and the finger, suggesting a high degree of mtDNA diversity. These two individuals from the same cave showed more diversity than seen among sampled Neanderthals from all of Eurasia, and were as different as modern-day humans from different continents.
Nuclear genome analysis
In the same second 2010 paper, the authors reported the isolation and sequencing of nuclear DNA from the Denisova finger bone. This specimen showed an unusual degree of DNA preservation and low level of contamination. They were able to achieve near-complete genomic sequencing, allowing a detailed comparison with Neanderthal and modern humans. From this analysis, they concluded, in spite of the apparent divergence of their mitochondrial sequence, that the Denisova population shared a common branch with Neanderthals from the lineage leading to modern African humans. The estimated average time of divergence between Denisovan and Neanderthal sequences is 640,000 years ago, and the time between both of these and the sequences of modern Africans is 804,000 years ago. They suggest that the divergence of the Denisova mtDNA results either from the persistence of a lineage purged from the other branches of humanity through genetic drift or else an introgression from an older hominin lineage.
In 2013, an mtDNA sequence from the femur of a 400,000-year-old Homo heidelbergensis from the Sima de los Huesos cave in Spain was found to be related to those of the Neanderthals and the Denisovans, but closer to the latter. Later analysis of nuclear DNA sequences from two specimens showed they were more closely related to Neanderthals rather than to Denisovans, while one of these samples also had the Denisovan-related mtDNA. The authors suggest that the mtDNA found in these specimens represents an archaic sequence indicative of Neanderthal's kinship with Denisovans that was subsequently lost in Neanderthals due to replacement by a more modern, human-related sequence.
In April 2014, a first glimpse into the epigenetics of the Denisovan was gained with the publication of the full DNA methylation of the Denisovan and the Neanderthal. The reconstructed DNA methylation map allowed researchers to assess gene activity levels throughout the Denisovan genome and compare them to modern humans and to the Neanderthal. The reconstruction was possible due to the natural degradation processes of ancient DNA, which leave different signals on methylated vs. unmethylated regions of the genome. The study found about 200 genes that show distinct regulatory patterns in the Denisovan.
A detailed comparison of the Denisovan, Neanderthal, and modern human genomes has revealed evidence for a complex web of interbreeding among the lineages. Through such interbreeding, 17% of the Denisova genome represents DNA from the local Neanderthal population, while evidence was also found of a contribution to the nuclear genome from an ancient hominin lineage yet to be identified, perhaps the source of the anomalously ancient mtDNA. DNA from this unidentified but highly archaic species that diverged from other populations over a million years ago represents as much as 8% of the Altai Denisovan genome. The Denisovan genome shared more derived alleles with the Altai Neanderthal genome from Siberia than with the Vindija cave Neanderthal genome from Croatia and the Mezmaiskaya cave Neanderthal genome from the Caucasus, suggesting that the gene flow came from a population that was more closely related to the Altai Neanderthal. The web of archaic human intermixing is highlighted by the genome from a 90,000-year-old bone fragment from the Denisova cave, found to have belonged to a Denisovan-Neanderthal hybrid female. Her Denisovan father had the typical Altai Neanderthal introgression, while her Neanderthal mother represented a population more closely related to Vindija Neanderthals than to those of Altai.
Analysis of genomes of modern humans show that they mated with at least two groups of archaic humans: Neanderthals (more similar to those found in the Caucasus than those from the Altai region) and Denisovans, and that such interbreedings occurred on multiple occasions. Approximately 1–4% of the DNA of non-African modern humans is shared with Neanderthals as a result of interbreeding. Tests comparing the Denisova hominin genome with those of six modern humans – a ǃKung from South Africa, a Nigerian, a Frenchman, a Papua New Guinean, a Bougainville Islander and a Han Chinese – showed that between 4 and 6% of the genome of Melanesians (represented by the Papua New Guinean and Bougainville Islander) derives from a Denisovan population; a later study puts the amount at 1.11% (with an additional contribution from some different and yet unknown ancestor). This DNA was possibly introduced during the early migration to Melanesia. These findings are in concordance with the results of other comparison tests which show a relative increase in allele sharing between the Denisovan and the Aboriginal Australian genome, compared to other Eurasians and African populations; however, Papuans, the population of Papua New Guinea, have more allele sharing than Aboriginal Australians.
Melanesians are not the only modern-day descendants of Denisovans. David Reich of Harvard University and Mark Stoneking of the Planck Institute team found genetic evidence that Denisovan ancestry is shared also by Australian Aborigines, and smaller scattered groups of people in Southeast Asia, such as the Mamanwa, a Negrito people in the Philippines, though not all Negritos were found to possess Denisovan genes; Onge Andaman Islanders and Malaysian Jehai, for example, were found to have no significant Denisovan inheritance. This suggests that interbreeding occurred in mainland South-East Asia, and that Denisovans once ranged widely over eastern Asia. Based on the modern distribution of Denisova DNA, Denisovans may have crossed the Wallace Line, with Wallacea serving as their last refugium. Small amounts of Denisovan DNA, representing around 0.2% Denisovan ancestry, are also found in mainland Asians and Native Americans.
Statistical analysis of genomic DNA sequences from different Asian populations indicates that at least two distinct populations of Denisovans existed, and that a second introgression event from Denisovans into humans occurred. A study of Han Chinese, Japanese and Dai genomes revealed that modern East Asian populations include two Denisovan DNA components: one similar to the Denisovan DNA found in Papuan genomes, and a second that is closer to the Denisovan genome from the Altai cave. These components were interpreted as representing separate introgression events involving two divergent Denisovan populations. South Asians were found to have levels of Denisovan admixture similar to that seen in East Asians, but this DNA only came from the same single Denisovan introgression seen in Papuans. Though there is no genomic evidence to support the hypothesis, the Red Deer Cave people of China have been suggested to have been the result of interbreeding between Homo sapiens and Denisovans within a few thousands years of the end of the last glacial period.
The immune system's HLA alleles have drawn particular attention in the attempt to identify genes that may derive from archaic human populations. Although not present in the sequenced Denisova genome, the distribution pattern and divergence of HLA-B*73 from other HLA alleles has led to the suggestion that it introgressed from Denisovans into humans in west Asia. As of 2011, half of the HLA alleles of modern Eurasians represent archaic HLA haplotypes, and have been inferred to be of Denisovan or Neanderthal origin. The apparent over-representation of these alleles suggests a positive selective pressure for their retention in the human population. A higher-quality Denisovan genome published in 2012 reveals variants of genes in humans that are associated with dark skin, brown hair, and brown eyes – consistent with features found with Melanesians today. A study involving 40 Han Chinese and 40 people of ethnic Tibetan background identified a region of DNA around the EPAS1 gene that assists with adaptation to low oxygen levels at high altitude found in Tibetans is also found in the Denisovan genome. In Papuans, introgressed Neanderthal alleles have highest frequency in genes expressed in brain, whereas Denisovan alleles have highest frequency in genes expressed in bones and other tissues.
- Gunbin, Konstantin V; Afonnikov, Dmitry A; Kolchanov, Nikolay A; Derevianko, Anatoly P; Rogaev, Eugeny I (2015). "The evolution of Homo sapiens denisova and Homo sapiens neanderthalensis miRNA targeting genes in the prenatal and postnatal brain". BMC Genomics. 16: S4. doi:10.1186/1471-2164-16-S13-S4. PMC 4686780. PMID 26693966.
- "Exploring Taxonomy". European Molecular Biology Laboratory, Wellcome Trust. Retrieved 27 October 2015.
- "Homo sapiens ssp. Denisova". Taxonomy Browser. NCBI. Retrieved 2015-10-28.
- "Taxonomy – Homo sapiens ssp. Denisova (Denisova hominin)". UniProt. Retrieved 2015-10-28.
- David Leveille (31 August 2012). "Scientists Map An Extinct Denisovan Girl's Genome". PRI's The World,. Retrieved 31 August 2012.
- Brown, David (25 March 2010), "DNA from bone shows new human forerunner, and raises array of questions", The Washington Post
- Krause, Johannes; Fu, Qiaomei; Good, Jeffrey M.; Viola, Bence; Shunkov, Michael V.; Derevianko, Anatoli P. & Pääbo, Svante (2010), "The complete mitochondrial DNA genome of an unknown hominin from southern Siberia", Nature, 464 (7290): 894–97, Bibcode:2010Natur.464..894K, doi:10.1038/nature08976, PMID 20336068
- Katsnelson, Alla (24 March 2010), "New hominin found via mtDNA", The Scientist
- Carl Zimmer (22 December 2010). "Denisovans Were Neanderthals' Cousins, DNA Analysis Reveals". NYTimes.com. Retrieved 22 December 2010.name="Callaway.
- "Callaway, Ewen (2011). "First Aboriginal genome sequenced". Nature. doi:10.1038/news.2011.551.
- "About 3% to 5% of the DNA of people from Melanesia (islands in the south-west Pacific Ocean), Australia and New Guinea as well as aboriginal people from the Philippines comes from the Denisovans." Oldest human DNA found in Spain – Elizabeth Landau's interview of Svante Paabo
- Harmon, Katherine (August 30, 2012). "Humans Interbred with Denisovans". Scientific American. Retrieved 2016-08-24.
- Pennisi, E (2013). "More Genomes from Denisova Cave Show Mixing of Early Human Groups". Science. 340 (6134): 799. doi:10.1126/science.340.6134.799. PMID 23687020.
- Zimmer, Carl (16 November 2015). "In a Tooth, DNA From Some Very Old Cousins, the Denisovans". The New York Times. Retrieved 16 November 2015.
- Sawyer, Susanna; Renaud, Gabriel; Viola, Bence; Hublin, Jean-Jacques; Gansauge, Marie-Theres; Shunkov, Michael V; Derevianko, Anatoly P; Prüfer, Kay; Kelso, Janet; Pääbo, Svante (2015). "Nuclear and mitochondrial DNA sequences from two Denisovan individuals". Proceedings of the National Academy of Sciences. 112 (51): 15696–700. doi:10.1073/pnas.1519905112. PMC 4697428. PMID 26630009.
- Felton, Bruce R (8 August 2018). "Neanderthal Genome Study Reveals Homo sapiens Lineage Diverged 744,000 Years Ago, Huge Gap in Fossil Record Indicated". AncientNews.net. Retrieved 23 August 2018.
- Marshall, Michael (5 April 2014). "Mystery Relations". New Scientist. 222 (2963): 34–38.
- Ovodov, ND; Crockford, SJ; Kuzmin, YV; Higham, TF; Hodgins, GW; van der Plicht, J (July 28, 2011). "A 33,000-Year-Old Incipient Dog from the Altai Mountains of Siberia: Evidence of the Earliest Domestication Disrupted by the Last Glacial Maximum – First paleontological survey was conducted by N.D. Ovodov in 1975". PLoS ONE. 6 (7): e22821. Bibcode:2011PLoSO...622821O. doi:10.1371/journal.pone.0022821. PMC 3145761. PMID 21829526. Retrieved December 9, 2015.
- Sample, Ian (24 March 2010), "New species of human ancestor found in Siberia", The Guardian
- Liesowska, Anna (7 May 2015). "Stone bracelet is oldest ever found in the world". The Siberia Times. Retrieved 23 August 2018.
- Mitchell, Alanna (30 January 2012). "DNA Turning Human Story Into a Tell-All". The New York Times. Retrieved 31 January 2012.
- Reich, David; Green, Richard E; Kircher, Martin; Krause, Johannes; Patterson, Nick; Durand, Eric Y; Viola, Bence; Briggs, Adrian W; Stenzel, Udo; Johnson, Philip L. F; Maricic, Tomislav; Good, Jeffrey M; Marques-Bonet, Tomas; Alkan, Can; Fu, Qiaomei; Mallick, Swapan; Li, Heng; Meyer, Matthias; Eichler, Evan E; Stoneking, Mark; Richards, Michael; Talamo, Sahra; Shunkov, Michael V; Derevianko, Anatoli P; Hublin, Jean-Jacques; Kelso, Janet; Slatkin, Montgomery; Pääbo, Svante (2010). "Genetic history of an archaic hominin group from Denisova Cave in Siberia" (Full text). Nature. 468 (7327): 1053–60. doi:10.1038/nature09710. PMC 4306417. PMID 21179161.
- Wei-Haas, Maya (22 August 2018). "Ancient Girl's Parents Were Two Different Human Species - Born 90,000 years ago, the child is the first direct evidence of interbreeding among Neanderthals and their cousins the Denisovans". National Geographic. Retrieved 25 August 2018.
- Warren, Matthew (22 August 2018). "Mum's a Neanderthal, Dad's a Denisovan: First discovery of an ancient-human hybrid - Genetic analysis uncovers a direct descendant of two different groups of early humans". Nature. 560: 417–418. doi:10.1038/d41586-018-06004-0. Retrieved 25 August 2018.
- Slon, Viviane; Viola, Bence; Renaud, Gabriel; Gansauge, Marie-Theres; Benazzi, Stefano; Sawyer, Susanna; Hublin, Jean-Jacques; Shunkov, Michael V; Derevianko, Anatoly P; Kelso, Janet; Prüfer, Kay; Meyer, Matthias; Pääbo, Svante (2017). "A fourth Denisovan individual". Science Advances. 3 (7): e1700186. doi:10.1126/sciadv.1700186. PMC 5501502. PMID 28695206.
- Wong, K. (24 March 2010). "No bones about it: ancient DNA from Siberia hints at previously unknown human relative". Scientific American. ISSN 0036-8733. Retrieved 30 August 2015.
- Callaway, Ewen (2010). "Fossil genome reveals ancestral link". Nature. 468 (7327): 1012. doi:10.1038/4681012a. PMID 21179140.
- Brown, Samantha; Higham, Thomas; Slon, Viviane; Pääbo, Svante (March 29, 2016). "Identification of a new hominin bone from Denisova Cave, Siberia using collagen fingerprinting and mitochondrial DNA analysis". Scientific Reports. 6: 23559. Bibcode:2016NatSR...623559B. doi:10.1038/srep23559. PMC 4810434. PMID 27020421.
- Barras, Colin (13 August 2011), "Stone Age toe could redraw human family tree", New Scientist
- Zimmer, Carl. "Toe Fossil Provides Complete Neanderthal Genome". The New York Times.
- Callaway, Ewen (2013). "Hominin DNA baffles experts". Nature. 504 (7478): 16–17. doi:10.1038/504016a.
- Tattersall, Ian (2015). The Strange Case of the Rickety Cossack and other Cautionary Tales from Human Evolution. Palgrave Macmillan. p. 200. ISBN 978-1-137-27889-0.
- Matthias Meyer, Juan-Luis Arsuaga, Cesare de Filippo, Sarah Nagel, Ayinuer Aximu-Petri, Birgit Nickel, Ignacio Martínez, Ana Gracia, José María Bermúdez de Castro, Eudald Carbonell, Bence Viola, Janet Kelso, Kay Prüfer & Svante Pääbo (2016). "Nuclear DNA sequences from the Middle Pleistocene Sima de los Huesos hominins". Nature. 531 (7595): 504–07. Bibcode:2016Natur.531..504M. doi:10.1038/nature17405. PMID 26976447.
- Gokhman D, Lavi E, Prüfer K, Fraga MF, Riancho JA, Kelso J, Pääbo S, Meshorer E, Carmel L (2014). "Reconstructing the DNA methylation maps of the Neandertal and the Denisovan". Science. 344 (6183): 523–27. Bibcode:2014Sci...344..523G. doi:10.1126/science.1250368. PMID 24786081.
- Holloway, April (30 January 2014). "New studies reveal 20 Percent of Neanderthal genome lives on in modern humans". ancient-origins.net. Retrieved 7 October 2016.
- Prüfer, K.; Racimo, Fe.; Patterson, N.; Jay, F.; Sankararaman, S.; Sawyer, S.; et al. (2013). "The complete genome sequence of a Neanderthal from the Altai Mountains". Nature. 505 (7481): 43–49. Bibcode:2014Natur.505...43P. doi:10.1038/nature12886. PMC 4031459. PMID 24352235.
- Briggs, Helen (22 August 2018). "Cave girl was half Neanderthal, half Denisovan". BBC news. Retrieved 22 August 2018.
- Marshall, Michael (22 August 2018). "Prehistoric girl had parents belonging to different human species". New Scientist. Retrieved 22 August 2018.
- Warren, Matthew (2018). "Mum's a Neanderthal, Dad's a Denisovan: First discovery of an ancient-human hybrid". Nature. 560: 417–18. doi:10.1038/d41586-018-06004-0.
- Green RE, Krause J, Briggs AW, et al. (May 2010). "A draft sequence of the Neandertal genome" (PDF). Science. 328 (5979): 710–22. Bibcode:2010Sci...328..710G. doi:10.1126/science.1188021. PMC 5100745. PMID 20448178.
- Zimmer, Carl (17 March 2016). "Humans Interbred With Hominins on Multiple Occasions, Study Finds". The New York Times. Retrieved 17 March 2016.
- Tina Hesman Saey, "DNA data offer evidence of unknown extinct human relative", Science News, Oct. 21, 2016. Retrieved 26 Feb. 2017.
- Rasmussen; et al. (Oct 2011). "An Aboriginal Australian genome reveals separate human dispersals into Asia". Science. 334 (6052): 94–98. Bibcode:2011Sci...334...94R. doi:10.1126/science.1211177. PMC 3991479. PMID 21940856.
- Callaway, Ewen (2011). "First Aboriginal genome sequenced". Nature. doi:10.1038/news.2011.551.
- Reich, David; Patterson, Nick; Kircher, Martin; Delfin, Frederick; Nandineni, Madhusudan R; Pugach, Irina; Ko, Albert Min-Shan; Ko, Ying-Chin; Jinam, Timothy A; Phipps, Maude E; Saitou, Naruya; Wollstein, Andreas; Kayser, Manfred; Pääbo, Svante; Stoneking, Mark (2011). "Denisova Admixture and the First Modern Human Dispersals into Southeast Asia and Oceania". The American Journal of Human Genetics. 89 (4): 516–28. doi:10.1016/j.ajhg.2011.09.005.
- Choi, Charles (22 September 2011), Now-Extinct Relative Had Sex with Humans Far and Wide, LiveScience
- Cooper, A; Stringer, C. B (2013). "Did the Denisovans Cross Wallace's Line?". Science. 342 (6156): 321–23. doi:10.1126/science.1244869.
- Salleh, Anna (13 October 2013). "Humans dated ancient Denisovan relatives beyond the Wallace Line". Australian Broadcasting Corporation. Retrieved 23 August 2018.
- Prüfer, Kay; Racimo, Fernando; Patterson, Nick; Jay, Flora; Sankararaman, Sriram; Sawyer, Susanna; Heinze, Anja; Renaud, Gabriel; Sudmant, Peter H; De Filippo, Cesare; Li, Heng; Mallick, Swapan; Dannemann, Michael; Fu, Qiaomei; Kircher, Martin; Kuhlwilm, Martin; Lachmann, Michael; Meyer, Matthias; Ongyerth, Matthias; Siebauer, Michael; Theunert, Christoph; Tandon, Arti; Moorjani, Priya; Pickrell, Joseph; Mullikin, James C; Vohr, Samuel H; Green, Richard E; Hellmann, Ines; Johnson, Philip L. F; et al. (2013). "The complete genome sequence of a Neanderthal from the Altai Mountains". Nature. 505 (7481): 43–49. doi:10.1038/nature12886. PMC 4031459.
- "Our ancestors mated with the mystery 'Denisovan' people – twice". New Scientist. 2018-03-15. Retrieved 2018-03-20.
- "New Sequence Analysis Suggests There Were Two Denisovan-Modern Human Admixture Events". genomeweb.com. 1 March 2018. Retrieved 23 August 2018.
- Browning, Sharon R.; Browning, Brian L.; Zhou, Ying; Tucci, Serena; Akey, Joshua M. (2018). "Analysis of Human Sequence Data Reveals Two Pulses of Archaic Denisovan Admixture". Cell. 173 (1): 53–61.e9. doi:10.1016/j.cell.2018.02.031. ISSN 0092-8674. PMC 5866234. PMID 29551270.
- Barras, Colin. "Chinese fossils unlike any known species". New Scientist (Reed Business Information). Retrieved 19 December 2013.
- Abi-Rached, L; Jobin, M. J; Kulkarni, S; McWhinnie, A; Dalva, K; Gragert, L; Babrzadeh, F; Gharizadeh, B; Luo, M; Plummer, F. A; Kimani, J; Carrington, M; Middleton, D; Rajalingam, R; Beksac, M; Marsh, S. G. E; Maiers, M; Guethlein, L. A; Tavoularis, S; Little, A.-M; Green, R. E; Norman, P. J; Parham, P (2011). "The Shaping of Modern Human Immune Systems by Multiregional Admixture with Archaic Humans". Science. 334 (6052): 89–94. doi:10.1126/science.1209202. PMC 3677943. PMID 21868630. Lay summary – BBC News (26 August 2011).
- Huerta-Sánchez, Emilia; Jin, Xin; Asan; Bianba, Zhuoma; Peter, Benjamin M; Vinckenbosch, Nicolas; Liang, Yu; Yi, Xin; He, Mingze; Somel, Mehmet; Ni, Peixiang; Wang, Bo; Ou, Xiaohua; Huasang; Luosang, Jiangbai; Cuo, Zha Xi Ping; Li, Kui; Gao, Guoyi; Yin, Ye; Wang, Wei; Zhang, Xiuqing; Xu, Xun; Yang, Huanming; Li, Yingrui; Wang, Jian; Wang, Jun; Nielsen, Rasmus (2014). "Altitude adaptation in Tibetans caused by introgression of Denisovan-like DNA". Nature. 512 (7513): 194–97. doi:10.1038/nature13408. PMC 4134395.
- Brahic, Catherine (5 July 2014). "Extinct humans primed Tibetans for the high life". New Scientist.
- Akkuratov, Evgeny E; Gelfand, Mikhail S; Khrameeva, Ekaterina E (2018). "Neanderthal and Denisovan ancestry in Papuans: A functional study". Journal of Bioinformatics and Computational Biology. 16 (2): 1840011. doi:10.1142/S0219720018400115. PMID 29739306.
- Barras, Colin (13 August 2011). "Stone Age toe could redraw human family tree". New Scientist.
- Fox, Maggie (24 March 2010). "Possible new human ancestor found in Siberia". Reuters.
- Ghosh, Pallab (22 December 2010). "Ancient humans, dubbed 'Denisovans', interbred with us". BBC News online.
The study shows that Denisovans interbred with the ancestors of the modern people of the Melanesian region north and north-east of Australia. Melanesian DNA comprises between 4% and 6% Denisovan DNA.
- Greshko, Michael (15 November 2015). "DNA Reveals Mysterious Human Cousin With Huge Teeth". National Geographic.
- Hawks, John (22 December 2010). "The Denisova genome FAQ". John Hawks Weblog.
- Rincon, Paul (25 March 2010). "DNA identifies new ancient human dubbed 'X-woman'". BBC News online.
- Shreeve, Jamie (July 2013). "The Case of the Missing Ancestor". National Geographic.
- Wade, Nicholas (24 March 2010). "Bone May Reveal a New Human Group". The New York Times.
- Wenz, John (27 August 2014). "The Other Neanderthal". The Atlantic.
- Zimmer, Carl (24 March 2010). "Hybrid speculation (blog)". Discover.
- Zimmer, Carl (22 December 2010). "Meet the Denisovans, the newest members of the human tree of life (blog)". Discover.