在19世紀,西方學術界為馬來人和美洲原住民是否應被歸類為蒙古人種發表了各式各樣的意見。例如,D. M. Warren在1856年根據蒙古人種的狹義定義而將馬來人和美洲原住民排除在外[13],赫胥黎和亞歷山大·溫切爾則分別在1870年和1881年將馬來人和美洲原住民歸類為蒙古人種[14][15]。而在1861年,法國動物學家伊西多爾·若弗魯瓦·聖希萊爾(英語:Isidore Geoffroy Saint-Hilaire)甚至將澳大利亞原住民列為蒙古人種的一個亞種[16]。
「蒙古人種」的定義最初與膚色無關,直到19世紀50年代,法國貴族阿蒂爾·德·戈比諾出版了一本名為《Essai sur l'inégalité des races humaines》的著作,才首次將人種以膚色分為三大類:白、黑、黃。在他定義下的「黃種人」包括所有在當時被其他學者歸類為蒙古人種的族群[17][18]。戈比諾的種族論述對希特勒影響深遠。在戈比諾眼中,「白種人」地位超然,「黃種人」在體質和智力上皆平庸[19]。
納粹德國體質人類學家在埃貢·弗賴赫爾·馮·埃克斯坦德特(Egon Freiherr von Eickstedt)亦採用與瑞斯利和阿魯納恰拉姆相同的分類法將尼泊爾、不丹、孟加拉、東印度、印度東北部部分地區、緬甸西部和斯里蘭卡的族群視作印度人和南蒙古人的混血種族[23]。他同時亦將緬甸中部、雲南、西藏南部、泰國和印度部分地區的族群命名為德昂人種(以緬甸德昂族命名)。在他的定義中,斯里蘭卡人、蒙達人、緬族、克倫族、克欽族、撣族、泰族、嶺南華人都是「混了血」的德昂人種[24][需要引文]。
美國人類學家卡爾頓·庫恩(Carleton S. Coon)在1961年發表了他的極具爭議的著作《種族起源》 ,他將智人分為五種:高加索人種、蒙古人種、澳大利亞人種、開普敦人種和剛果人種[26]。庫恩的論點是,直立人本身就分為五種,然後又各自演化成智人[27]。但由於庫恩是依循傳統體質人類學依賴形態特徵的判斷法而非以新興的遺傳學來區分人種,因此他的《種族起源》被視為快被取代的過時科學方法的苟延殘喘[26]:249[28]。
German: "sehr willkürlich": Johann Friedrich Blumenbach. Handbuch der Naturgeschichte. 1797: 61 [2020-05-24]. (原始內容存檔於2021-12-21). Alle diese Verschiedenheiten fließen aber durch so mancherley Abstufungen und Uebergänge so unvermerkt zusammen, daß sich keine andre, als sehr willkürliche Grenzen zwischen ihnen festsetzen lassen.
Huxley, T. H.On the Geographical Distribution of the Chief Modifications of Mankind (頁面存檔備份,存於網際網路檔案館) (1870) Journal of the Ethnological Society of London. Huxley indicates that he has omitted certain areas with complex ethnic compositions that do not fit into his racial paradigm, including much of the Indian subcontinent and Horn of Africa. (Huxley, Thomas (1873). Critiques and Addresses by Thomas Henry Huxley, LL.D., F.R.S. Macmillan and Company. p. 153.) By the late nineteenth century, his Xanthochroi group had been redefined as the Nordic race, whereas his Melanochroi became the Mediterranean race. As such, Huxley's Melanochroi eventually also comprised various other dark Caucasoid populations, including the Hamites and Moors. (Gregory, John Walter (1931). Race as a Political Factor. Watts & Company. p. 19. Retrieved 8 May 2016.)
Ibram X. Kendi, Stamped from the Beginning. The Definitive History of Racist Ideas in America, New York: Nation Books 2016. ISBN978-1-5685-8464-5, chapters 4, 7–12, 14, 16 passim.
Winchell, A. (1881). Preadamites; or A Demonstration of the Existence of Men Before Adam; (3rd ed.). Chicago: S.C. Griggs and Company; London: Trubner & Co. pp. 57, 66.
von Eickstedt, Egon Frhr. Die Indien-Expedition des Staatlichen Forschungsinstituts für Völkerkunde in Leipzig. 1. Anthropologischer Bericht. Anthropologischer Anzeiger. 2018-04-21, 4 (3): 208–219. JSTOR 29535004.
Jackson Jr., John. "In Ways Unacademical": The Reception of Carleton S. Coon's The Origin of Races. Journal of the History of Biology. June 2001, 34 (2): 247–285. JSTOR 4331661. S2CID 86739986. doi:10.1023/A:1010366015968.
Cited according to Jackson Jr., John. "In Ways Unacademical": The Reception of Carleton S. Coon's The Origin of Races. Journal of the History of Biology. June 2001, 34 (2): 248. JSTOR 4331661. S2CID 86739986. doi:10.1023/A:1010366015968. The reference given there is to "Coon, Origin of the [sic] Races, 1963 [sic], p. 657".
"Indeed, if a species has sufficient gene flow, there can be no evolutionary tree of populations, because there are no population splits...", Templeton, A. (2016). EVOLUTION AND NOTIONS OF HUMAN RACE. In Losos J. & Lenski R. (Eds.), How Evolution Shapes Our Lives: Essays on Biology and Society (p. 355). Princeton; Oxford: Princeton University Press. doi:10.2307/j.ctv7h0s6j.26.
Nägele, Kathrin; Rivollat, Maite; Yu, He; Wang, Ke. Ancient genomic research - From broad strokes to nuanced reconstructions of the past. Journal of Anthropological Sciences. 2022, 100 (100): 193–230. PMID 36576953. doi:10.4436/jass.10017.
Kanazawa, Satoshi. The evolution of general intelligence. Personality and Individual Differences. 2012-07-01, 53 (2): 90–93. ISSN 0191-8869. doi:10.1016/j.paid.2011.05.015(英語).
"The importance of this anomaly among Europeans and their descendants is not related to the segregation of genes derived from Asians; its appearance among members of Asian populations suggests such ambiguous designations as 'Mongol Mongoloid'; increasing participation of Chinese and Japanese in investigation of the condition imposes on them the use of an embarrassing term. We urge, therefore, that the expressions which imply a racial aspect of the condition be no longer used. Some of the undersigned are inclined to replace the term Mongolism by such designations as 'Langdon Down Anomaly', or 'Down's Syndrome or Anomaly', or 'Congenital Acromicria'. Several of us believe that this is an appropriate time to introduce the term 'Trisomy 21 Anomaly', which would include cases of simple Trisomy as well as translocations. It is hoped that agreement on a specific phrase will soon crystallise once the term 'Mongolism' has been abandoned."
Allen, G. Benda C.J. et al (1961). Lancet corr. 1, 775.