"Racial categorization has a long history, and may be related to a deep-rooted psychological need to quickly identify potential enemies and allies [101]. However, the biological reality is different and, for humans, it is one of continuous variation [75], clines, and genetic boundaries that cross the geographic space without surrounding and thus defining specific isolated groups of populations [102]
[...]
They confirmed that the direct analysis of discrete samples tends to suggest the existence of clusters, roughly corresponding to continents. However, these clusters disappeared when the unit of analysis became the randomly-sampled individual, indicating that discontinuities are probably an artefact due to the discontinuous design of that and other studies. Therefore, assigning individual genotypes to groups apparently conceals the continuous nature of human diversity and entails a high degree of arbitrariness
[...]
But studies of protein or DNA polymorphisms have not shown so far is that there are clear-cut geographic discontinuities in the distribution of human genome diversity, and that clusters found for one set of markers will stay the same when different markers are considered." (Barbujani, 2005).
Typological thinking is a product of parochialism, ignorance and possibly imperialism in this case. Try not to forget that Europeans encountered much of the world by sea, which means they encountered a discontinuous population and made the same faulty conclusion that Barbujani (2005) has explained above. If you looked at how Africans (or anybody seen as the 'other' (Said's 'Orientalism', for example)) were depicted and written about in colonialist literature, it will become immediately apparent that imperialism and 'race'/typological thinking are inextricable concepts.
Let us also remember that this myth that there are X number of immediately perceptible differences amongst people that enable people to sort others into definitive 'races'
is just a myth that is a product of sheer ignorance and arbitrary assignment:
"According to some modern authors [see e.g. Refs. 28-30], the classical analyses of morphological traits, such as skeletal measures or skin color, suggest a clear racial subdivision. On the contrary, a review of the relevant literature shows that that is not the case [26, 31]. Indeed, although until 1962 nobody explicitly raised doubts on the existence of biological races in humans [32], studies of human morphology from Linnaeus to current times reached no consensus on which races exist, and which populations belong to which race. Lists compiled by serious scientists include anything between three and 200 different races [33], and it is impossible for me to identify in these lists anything that can be called ‘common concepts’ of race" (Barbujani, 2005).
"The admittedly incomplete scheme of Table 1 is based on Refs. [8, 26, 29, 32]."
"[T]he term ‘Negro’ was once a racial designation for numerous groups in tropical Africa and Pacific Oceania (Melanesians). These groups share a broadly similar external phenotype; this classification illustrates ‘race’ as type, defined by anatomical complexes. Although the actual relationship between African ‘Negroes’ and Oceanic ‘Negroes’ was sometimes questioned, these groups were placed in the same taxon. Molecular and genetic studies later showed that the Oceanic ‘Negroes’ were more closely related to mainland Asians." (Keita
et al., 2004).
Finally, Mishler's (2009) critique of Linnean taxonomy holds true: "Ranked classifications are a hold-over from the pre-Darwinian creationist mindset (Ereshefsky, 2002). They are not just a quaint anachronism; they are resulting in miscommunication at many levels" (Mishler, 2009).
Anything else?