The Andamanese resemble other Negrito groups in Asia. They are pygmies, and are the only modern people outside of certain parts of Africa with steatopygia. They lead a hunter-gatherer lifestyle, and appear to have lived in substantial isolation for thousands of years. This degree of isolation is unequaled, except perhaps by the aboriginal inhabitants of Tasmania. The Andamanese are believed to be descended from the migrations which, about 60,000 years ago, brought the first modern humans out of Africa to the Andaman Islands.
By the end of the 18th century, when they first came into sustained contact with outsiders, there were an estimated 7,000 Andamanese divided into five major groups. Each group had distinct cultures, separate domains and mutually unintelligible languages. In the next century they were largely wiped out by diseases, violence, and loss of territory. Today, there remain only around 400–450 Andamanese. One group has long been extinct, and only two of the remaining groups still maintain a steadfast independence, refusing most attempts at contact by outsiders.
The five major groups of Andamanese found by the European colonists were:
- Great Andamanese, extinct 54 Admixed Individuals 
- Jarawa now estimated 250 to 400 verified to exist in pure form
- Jangil or Rutland Jarawa, extinct
- Onge, now fewer than 100 verified to exist in pure form
- Sentinelese, now estimated to be 100 to 200.
- Great Andamanese are completely dominated by South-Asian male lines meaning they are admixed, Jarawa and Onge are dominated
by D y-dna which is native to the Andamanese 
By the end of the 18th century, there were an estimated 5,000 Great Andamanese living on Great Andaman. Altogether they comprised 10 distinct tribes with different languages. The population quickly dwindled until they went extinct in pure form , had a low of 19 admixed individuals by 1961. It has increased slowly after that, following their move to a reservation on Strait Island. By January 2011, there were only 54 admixed individuals from three tribes, who spoke mostly Hindi.
The Jarawa originally inhabited southeastern Jarawa Island and have migrated to the west coast of Great Andaman in the wake of the Great Andamanese. The Onge once lived throughout Little Andaman and are now confined to two reservations on the island. The Jangil, who originally inhabited Rutland Island, were extinct by 1931; the last individual was sighted in 1907. Only the Sentinelese are still living in their original homeland on North Sentinel Island, largely undisturbed, and have fiercely resisted all attempts at contact.
It is assumed that those ancestors were part of the initial Great Coastal Migration that was the first expansion of humanity out of Africa, via the Arabian peninsula, along the coastal regions of the Indian mainland and towards Southeast Asia, Japan and Oceania.
Some anthropologists postulate that Southern India and Southeast Asia was once populated largely by Negritos similar to those of the Andamans, and that some tribal populations in the south of India, such as the Irulas are remnants of that period.
Until the late 18th century, the Andamanese culture, language and genetics were preserved from outside influences by their fierce reaction to visitors, which included killing any shipwrecked foreigners, and by the remoteness of the islands. The various tribes and their mutually unintelligible languages are thus believed to have evolved on their own over millennia.
The analysis of nuclear DNA confirms the uniqueness of the Andamanese people. First, they show a very small genetic variation, which is indicative of populations that have experienced a population bottleneck and then developed in isolation for a long period. Second, an allele has been discovered among the Jarawas which is found nowhere else in the world. Overall, the Andamanese showed closest relations with other Asian populations. The Nicobarese were also observed to share close genetic relations with adjacent Indo-Mongoloid populations of Northeast India. Bulbeck (2013) likewise noted that the Andamanese's nuclear DNA clusters with that of other South Asians.
A genome-wide study by Reich et al. (2009) found evidence for two genetically divergent, ancient populations that are ancestral to most persons inhabiting the Indian subcontinent today: Ancestral North Indians (ANI), who are genetically close to Middle Eastern, Central Asian and European populations, and Ancestral South Indians (ASI), who are genetically distinct from both ANI and East Asians. The Onge Andamanese were observed to be related to the Ancestral South Indians, and were unique in that they were the only South Asian population in the study that lacked any Ancestral North Indian admixture. The authors thus suggest that the Onge populated the Andamanese Islands prior to the intermixture that took place between the Ancestral South Indians and Ancestral North Indians on the Indian mainland.
The male Y-chromosome in humans is inherited exclusively through paternal descent. Male Onges and Jarawas almost exclusively belong to Haplogroup D-M174. The clade is most common today in Tibet and Japan, with its highest frequencies worldwide in the Pumi population of northwestern China (70.2%). Haplogroup D-M174 also occurs frequently among the Ainu. On the Indian mainland, it has been observed at low frequencies. Andamanese males were found to carry five different binary D haplotypes, all of which had previously been observed on the Indian subcontinent, in Southeast Asia and Melanesia.
Male Great Andamanese do not have D-M174.The low resolution study discovered these clades as O, L, K and P-M45, which means that Great Andamanese are extinct in pure form as all of their male lines have a post 1900 foreign origin and around half of their blood.
Analysis of mtDNA, which is inherited exclusively by maternal descent, confirms the above results. All Andamanese belong to the subgroup M which is distributed in the Indian subcontinent, where it represents 60% of all maternal lineages, but also in Africa and other areas west of India. Given the insularity of the Andamanese, this has led geneticists to believe that this haplogroup originated with the earliest settlers of India during the coastal migration that brought the ancestors of the Andamanese to the Indian mainland, the Andaman Islands and further afield to Southeast Asia.
Furthermore, on the Andamans, M4 occurs as a subtype also seen on the Indian mainland, whereas M2 occurs in two subgroups (M2 haplotypes 16344T and 16357C) that have not been observed on the mainland and are presumed unique to the Andamanese. This implies a long history of the Andamanese on the islands, which would allow the time for insulated local genetic development. Since the M2 and M4 lineages diverged 60,000-30,000 years before present and both occur outside the Andamans, it is likely that the Andaman islands were originally colonized by bearers of the two different haplogroups.
The Andamanese's protective isolation changed with the first British colonial presence and subsequent settlements, which proved disastrous for them. Lacking immunity against common diseases of the Eurasian mainland, the large Jarawa habitats on the southeastern regions of South Andaman Island were likely depopulated by disease within four years (1789-1793) of the initial British colonial settlement in 1789. Epidemics of pneumonia, measles and influenza spread rapidly and exacted heavy tolls, as did alcoholism. By 1875, the Andamanese were already "perilously close to extinction," yet attempts to contact, subdue and co-opt them continued unrelentingly. In 1888, the British government set in place a policy of "organized gift giving" that continued in varying forms until well into the 20th century.
There is evidence that some sections of the British Indian administration were deliberately working to annihilate the tribes. After the mid-19th century, British established penal colonies on the islands and an increasing numbers of mainland Indian and Karen settlers arrived, encroaching on former territories of the Andamanese. This accelerated the decline of the tribes.
Many Andamanese succumbed to British expeditions, to avenge the killing of shipwrecked sailors. In the 1867 Andaman Islands Expedition, dozens of Onge were killed by British naval personnel following the death of shipwrecked sailors, which resulted in four Victoria Crosses for the British soldiers. In the 1940s, the Jarawa were bombed by Japanese forces for their hostility.
In 1974, a film crew and anthropologist Trilokinath Pandit attempted friendly contact by leaving a tethered pig, some pots and pans, some fruit and toys on the beach at North Sentinel Island. One of the islanders shot the film director in the thigh with an arrow. The following year, European visitors were repulsed with arrows.
On 2 August 1981, the ship Primrose grounded on the North Sentinel Island reef. A few days later, crewmen on the immobile vessel observed that small black men were carrying spears and arrows and building boats on the beach. The captain of the Primrose radioed for an urgent airdrop of firearms so the crew could defend themselves but did not receive them. Heavy seas kept the islanders away from the ship. After a week, the crew were rescued by an Indian navy helicopter.
On 4 January 1991, Indian scholar Trilokinath Pandit made the first known friendly contact with the Sentinelese.
Until 1996, the Jarawa met most visitors with flying arrows. From time to time they attacked and killed poachers on the lands reserved to them by the Indian government. They also killed some workers building the Andaman Trunk Road (ATR), which traverses Jarawa lands. One of the earliest peaceful contacts with the Jarawa occurred in 1996. Settlers found a teenage Jarawa boy named Emmei near Kadamtala town. The boy was immobilized with a broken foot. They took Emmei to a hospital where he received good care. Over several weeks, Emmei learned a few words of Hindi before returning to his jungle home. The following year, Jarawa individuals and small groups began appearing along roadsides and occasionally venturing into settlements to steal food. The ATR may have interfered with traditional Jarawa food sources.
Until contact, the Andamanese were strict hunter-gatherers. They did not practice cultivation, and lived off hunting indigenous pigs, fishing, and gathering. Their only weapons were the bow, adzes and wooden harpoons. Besides the aboriginal people of Tasmania, the Andamanese were the only people who in the 19th century knew no method of making fire. They instead carefully preserved embers in hollowed-out trees from fires caused by lightning strikes. They are known as Chadda
- Andamanese languages
- Uncontacted peoples
- Australoid race
- Early human migrations
- "List of notified Scheduled Tribes". Census India. p. 27. Retrieved 15 December 2013.
- Anosh Malekar, "The case for a linguisitic survey," Infochange Media, August 1, 2011.
- George van Driem (2001), Languages of the Himalayas: An Ethnolinguistic Handbook of the Greater Himalayan Region: Containing an Introduction to the Symbiotic Theory of Language, BRILL, ISBN 90-04-12062-9, "... The Aka-Kol tribe of Middle Andaman went extinct by 1921. The Oko-Juwoi of Middle Andaman and the Aka-Bea of South Andaman and Rutland Island were extinct by 1931. The Akar-Bale of Ritchie's Archipelago, the Aka-Kede of Middle Andaman and the A-Pucikwar of South Andaman Island soon followed. By 1951, the census counted a total of only 23 Greater Andamanese and 10 Sentinelese. That means that just ten men, twelve women and one child remained of the Aka-Kora, Aka-Cari and Aka-Jeru tribes of Greater Andaman and only ten natives of North Sentinel Island ..."
- Jayanta Sarkar (1990), The Jarawa, Anthropological Survey of India, ISBN 81-7046-080-8, "The Great Andamanese population was large till 1858 when it started declining ... In 1901, their number was reduced to only 600 and in 1961 to a mere 19."
- Spencer Wells (2002), The Journey of Man: A Genetic Odyssey, Princeton University Press, ISBN 0-691-11532-X, "... the population of south-east Asia prior to 6000 years ago was composed largely of groups of hunter-gatherers very similar to modern Negritos ... So, both the Y-chromosome and the mtDNA paint a clear picture of a coastal leap from Africa to south-east Asia, and onward to Australia ... DNA has given us a glimpse of the voyage, which almost certainly followed a coastal route va India ..."
- Anvita Abbi (2006), Endangered Languages of the Andaman Islands, Lincom Europa, "... to Myanmar by a land bridge during the ice ages, and it is possible that the ancestors of the Andamanese reached the islands without crossing the sea ... The latest figure in 2005 is 50 in all ..."
- Jim Mason (2005), An Unnatural Order: The Roots of Our Destruction of Nature, Lantern Books, ISBN 1-59056-081-7, "... Australia's "aboriginal" peoples are another case in point. At the end of the Ice Age, their homeland stretched from the middle of India eastward into southeast Asia and as far south as Indonesia and nearby islands. As agriculture spread from its centers in southeast Asia, these pre-Australoid forager people moved farther southward to New Guinea and Australia. ..."
- K.V. Zvelebil (1982), The Irula language, O. Harrassowitz, ISBN 3-447-02247-7, "... into the low jungles of the Nilgiris (such movement might have been instigated e.g. by the advancing Australoids pushing out an earlier pre-Australoid ..."
- Stephen Fuchs (1974), The Aboriginal Tribes of India, Macmillan India, ISBN 0-333-19782-8, "... Guha thinks that the Negritos were the earliest racial element in India. He believes that the Kadar, Irulas and Panyans of south India have a Negrito strain, even though he admits that they are not pure Negritos ..."
- V. K. Kashyap, Sitalaximi T., B. N. Sarkar, R. Trivedi1 (2003), "Molecular Relatedness of The Aboriginal Groups of Andaman and Nicobar Islands with Similar Ethnic Populations", International Journal of Human Genetics, 3(1): 5-11 (2003), retrieved 2009-06-08, "... the Negrito populations of Andaman Islands have remained in isolation ... the Andamanese are more closely related to other Asians than to modern day Africans ... the Nicobarese exhibiting a close affinity with geographically proximate Indo-Mongoloid populations of Northeast India ..."
- M. Phillip Endicott, Thomas P. Gilbert, Chris Stringer, Carles Lalueza-Fox, Eske Willerslev, Anders J. Hansen, Alan Cooper (2003), "The Genetic Origins of the Andaman Islanders", American Journal of Human Genetics 72 (1): 178–184, doi:10.1086/345487, PMC 378623, PMID 12478481, retrieved 2009-04-21, "... The HVR-1 data separate them into two lineages, identified on the Indian mainland (Bamshad et al. 2001) as M4 and M2 ... The Andamanese M2 contains two haplotypes ... developed in situ, after an early colonization ... Alternatively, it is possible that the haplotypes have become extinct in India or are present at a low frequency and have not yet been sampled, but, in each case, an early settlement of the Andaman Islands by an M2-bearing population is implied ... The Andaman M4 haplotype ... is still present among populations in India, suggesting it was subject to the late Pleistocene population expansions ..."
- Bulbeck, David (November 2013). "Craniodental Affinities of Southeast Asia's "Negritos" and the Concordance with Their Genetic Affinities". Human Biology 85 (1). Retrieved 17 December 2013.
- Reich, David; Kumarasamy Thangaraj; Nick Patterson; Alkes L. Price; Lalji Singh (24 September 2009). "Reconstructing Indian Population History". Nature 461 (7263): 489–494. doi:10.1038/nature08365. PMC 2842210. PMID 19779445. Retrieved 12 November 2013.
- "Y-DNA Haplogroup D and its Subclades - 2008". Isogg.org. Retrieved 2010-05-14.
- Wen, Bo; et al. (May 2004). "Analyses of Genetic Structure of Tibeto-Burman Populations Reveals Sex-Biased Admixture in Southern Tibeto-Burmans". American Journal Human Genetics 5 (74): 856–865. doi:10.1086/386292. PMC 1181980. Retrieved 17 December 2013.
- Tajima, Atsushi; et al. (2004), "Genetic origins of the Ainu inferred from combined DNA analyses of maternal and paternal lineages", Journal of Human Genetics 49 (4): 187–193, doi:10.1007/s10038-004-0131-x, PMID 14997363
- Kumarasamy Thangaraj, Lalji Singh, Alla G. Reddy, V. Raghavendra Rao, Subhash C. Sehgal, Peter A. Underhill, Melanie Pierson, Ian G. Frame, and Erika Hagelberg (2002), Genetic Affinities of the Andaman Islanders, a Vanishing Human Population (PDF), archived from the original on 29 October 2008, retrieved 2008-11-16, "... Our data indicate that the Andamanese have closer affinities to Asian than to African populations and suggest that they are the descendants of the early Palaeolithic colonizers of Southeast Asia ... All Onge and Jarawa had the same binary haplotype D ... Great Andaman males had five different binary haplotypes, found previously in Southeast Asia, the Indian subcontinent, and Melanesia ..."
- Michael D. Petraglia, Bridget Allchin (2007), The evolution and history of human populations in South Asia, Springer, ISBN 1-4020-5561-7, "... As haplogroup M, except for the African sub-clade M1, is not notably present in regions west of the Indian subcontinent, while it covers the majority of Indian mtDNA variation ..."
- Revathi Rajkumar et al., Phylogeny and antiquity of M macrohaplogroup inferred from complete mt DNA sequence of Indian specific lineages, BMC Evolutionary Biology 2005, 5:26 doi:10.1186/1471-2148-5-26
- Phillip Endicott, M. Thomas P. Gilbert, Chris Stringer, Carles Lalueza-Fox, Eske Willerslev, Anders J. Hansen, and Alan Cooper (1 January 2002), "The Genetic Origins of the Andaman Islanders", American Journal of Human Genetics (The American Society of Human Genetics) 72 (1): 178–84, doi:10.1086/345487, PMC 378623, PMID 12478481, "... The high frequency of M2 is consistent with its greater age, and its distribution suggests that many of the populations viewed as the autochthons of India because of their cultural inheritance may also be genetic descendants of the early settlers of southern Asia ..."
- Choi, Charles (22 September 2011), Now-Extinct Relative Had Sex with Humans Far and Wide, LiveScience
- Sita Venkateswar (2004), Development and Ethnocide: Colonial Practices in the Andaman Islands, IWGIA, ISBN 87-91563-04-6, "As I have suggested previously, it is probable that some disease was introduced among the coastal groups by Lieutenant Colebrooke and Blair's first settlement in 1789, resulting in a marked reduction of their population. The four years that the British occupied their initial site on the south-east of South Andaman were sufficient to have decimated the coastal populations of the groups referred to as Jarawa by the Aka-bea-da."
- Richard B. Lee, Richard Heywood Daly (1999), The Cambridge Encyclopedia of Hunters and Gatherers, Cambridge University Press, ISBN 0-521-57109-X, "By 1875, when these peoples were perilously close to extinction, the Andaman cultures came under scientific scrutiny ... In 1888, 'friendly relations' were established with Ongees through organized gift giving contacts ... As recently as 1985—92, government contacts have been initiated with Jarawas and Sentinelese through gift-giving, a contact procedure much like that carried out during British rule."
- Luigi Luca Cavalli-Sforza, Francesco Cavalli-Sforza (1995), The Great Human Diasporas: The History of Diversity and Evolution, Basic Books, ISBN 0-201-44231-0, "Contact with whites, and the British in particular, has virtually destroyed them. Illness, alcohol, and the will of the colonials all played their part; the British governor of the time mentions in his diary that he received instructions to destroy them with alcohol and opium. He succeeded completely with one group. The others reacted violently."
- Madhusree Mukerjee (2003), The Land of Naked People, Houghton Mifflin Books, ISBN 0-618-19736-2, "In 1927 Egon Freiherr von Eickstedt, a German anthropologist, found that around one hundred Great Andamanese survived, 'in dirty, half-closed huts, which primarily contain cheap European household effects'."
- The London Gazette: . 17 December 1867. Retrieved 2008-08-23.
- Laxman Prasad Mathur (2003), Kala Pani: History of Andaman & Nicobar Islands, with a Study of Indiaʼs Freedom Struggle, Eastern Book Corporation, "Snippet: "Immediately afterwards in another visit to Little Andaman to trace the sailors of a ship named 'Assam Valley' wrecked on its coast, Homfray's party was attacked by a large group of Onges.""
- "The Last Island of the Savages". American Scholar. 22 September 2000.
- "Islanders running out of isolation: Tim McGirk in the Andaman Islands reports on the fate of the Sentinelese". The Independent (London). 10 January 1993.
- Vallely, Paul (4 December 2003). "Appeal: Under threat: an ancient tribe emerging from the forests". The Independent (London).