(a) Examine critically the concept of social stratification as a basis for sustaining social inequality. 20 marks (b) Describe…

(a) Social stratification as a basis for sustaining inequality

Social inequality is the unequal distribution of valued things: wealth, power, prestige and life chances. Social stratification is the institutionalised ranking of whole categories of people into layers (strata) that persist across generations. Stratification therefore turns inequality into a durable structure. Morton Fried distinguished egalitarian societies (many foragers), rank societies (unequal prestige but open access to resources, as among many chiefdoms) and stratified societies, where some groups have privileged access to basic resources.

Functionalist view. Durkheim saw a division of labour as integrating society, and Parsons saw ranking as reflecting shared values. The Davis–Moore thesis (1945) argued that stratification is universal and necessary: higher rewards attract the most able people to the most important positions.

• Critique: Melvin Tumin (1953) replied that "importance" is hard to measure, that inherited privilege blocks talent from below, and that stratification creates hostility and wastes ability. It explains why inequality is justified far better than why it exists.

Conflict view. For Marx, classes arise from ownership or non-ownership of the means of production; stratification sustains exploitation, and ideology makes it appear natural. Weber broadened this into three dimensions: class (market position), status (social honour and lifestyle) and party (power). He showed how status groups practise "social closure" through endogamy, commensality and control of credentials.

• Critique: the conflict view underplays mobility, consensus and the role of skill.

Caste as the Indian case

• Louis Dumont (Homo Hierarchicus, 1966): caste rests on the opposition of purity and impurity, with ritual status (Brahmin) encompassing political power (Kshatriya). Critics say this is a Brahminical, text-based view.
• M. N. Srinivas: his fieldwork in Rampura introduced the "dominant caste", whose power rests on land, numbers and politics rather than ritual rank alone. He also described "Sanskritisation", in which lower castes adopt upper-caste practices to rise, which shows that the system allows collective mobility.
• André Béteille (Caste, Class and Power, 1965, Sripuram): in modern India caste, class and power have become partly separate.
• Gerald Berreman: viewed from below, caste resembles racial stratification, and lower castes do not accept its justification.
• B. R. Ambedkar: called caste "graded inequality", in which each layer looks down on the one below, dividing the oppressed.

Tribal societies are usually less stratified, but hierarchy exists. The Konyak Nagas have hereditary chiefs (Angs), and among the Gonds, Raj Gond lineages once held ruling status.

Critical assessment

• Mechanisms that sustain inequality: inheritance of property, endogamy, unequal access to education and networks, residential segregation, stigma (untouchability), and ideologies such as karma or "merit" that make hierarchy seem legitimate.

Counter-forces:

• Constitutional guarantees: Articles 15, 16, 17 and 46, and the SC/ST (Prevention of Atrocities) Act, 1989.
• Reservations: upheld for OBCs in Indra Sawhney (1992). In State of Punjab v. Davinder Singh (2024), the Supreme Court allowed states to sub-classify Scheduled Castes so that benefits reach the least advantaged groups.
• Other drivers of mobility: urbanisation, education and political mobilisation, which have produced upward movement and new elites.
• Persistence: caste still shapes marriage, landholding and occupational concentration, and new inequalities of class and region overlap with old ones.

Stratification is thus neither simply functional nor simply exploitative. It is a socially constructed and contested structure that sustains inequality by making advantage inheritable, while leaving room for mobility through collective action and state policy.

(b) Genetics and inheritance of the ABO and Rh blood groups

ABO system. Landsteiner discovered it in 1900. It is controlled by the ABO gene on chromosome 9 (9q34), which has three main alleles (multiple allelism): Iᴬ, Iᴮ and i.

• All three act on a precursor, the H substance, made by the FUT1 gene on chromosome 19.
• Iᴬ encodes a glycosyltransferase that adds N-acetylgalactosamine, giving the A antigen. Iᴮ adds galactose, giving the B antigen.
• The common O allele has a single-base deletion that produces an inactive enzyme, so the H substance stays unchanged.
• Iᴬ and Iᴮ are codominant, and both are dominant over i. Six genotypes therefore give four phenotypes.
• Antibodies against the missing antigens (anti-A, anti-B; mainly IgM) are present naturally from early infancy. That is why transfusion must match ABO type.

Rh system. Landsteiner and Wiener described it in 1940. It is coded on chromosome 1 (1p36) by two neighbouring genes, RHD and RHCE.

• People with the D antigen are Rh-positive. Rh-negative people usually lack the RHD gene altogether, which is common in Europeans. "d" therefore means the absence of D, and Rh-negative is recessive (dd).
• Fisher–Race notation (CDE) describes the linked antigens C/c, D and E/e, which are inherited together as haplotypes.
• Anti-D is not natural. It forms only after exposure to D-positive cells, through transfusion or pregnancy.

Rh incompatibility. An Rh-negative mother carrying an Rh-positive fetus can be sensitised at delivery. Her IgG anti-D can then cross the placenta in a later pregnancy and cause haemolytic disease of the newborn (erythroblastosis fetalis). Anti-D immunoglobulin given at about 28 weeks and within 72 hours of delivery prevents this. When mother and fetus are also ABO-incompatible, the risk of sensitisation falls, because fetal cells are destroyed quickly.

Bombay phenotype (Oh). Bhende and colleagues described it in Mumbai in 1952. People with the genotype hh cannot make the H substance, so they type as O even when they carry Iᴬ or Iᴮ. They have anti-H in their plasma and can receive blood only from other Bombay-phenotype donors. It is an example of epistasis.

Population variation

• ABO: the O allele is very common among Native Americans, while B is frequent in Central and South Asia. In India, O and B are the commonest groups, each close to a third of people, with A at about a fifth and AB under a tenth.
• Rh: about 15% of Europeans are Rh-negative, and the Basques have the highest frequency. The figure is about 5% in India and under 1% in East Asians.

Uses in anthropology

• Classical serological surveys, such as those of D. N. Majumdar and later the Anthropological Survey of India, used these frequencies to study affinity, gene flow and genetic drift among castes and tribes.
• Selection has shaped the frequencies. Group O protects against severe falciparum malaria but is linked to more severe cholera, and Rh incompatibility selects against heterozygotes.
• In forensic work, ABO typing once served for exclusion in paternity and crime-scene cases, before DNA profiling replaced it.

(c) The synergy of biology and culture in human evolution

Biological evolution is change in gene frequencies through mutation, selection, drift and gene flow, passed on genetically. Cultural evolution is change in learned, socially transmitted behaviour (tools, language, institutions), which spreads much faster and can pass between unrelated people. The two are not separate tracks. Culture changes the environment in which genes are selected, and evolved biology makes new culture possible. This is gene–culture coevolution, or dual inheritance theory (Cavalli-Sforza and Feldman, 1981; Boyd and Richerson, 1985).

Stages of the feedback

• Tools and brains: stone tools appear by 3.3 Ma (Lomekwi) and the Oldowan by 2.6 Ma. Sherwood Washburn ("Tools and Human Evolution", 1960) argued that tool use selected for larger brains, skilled hands and bipedalism, which in turn allowed better tools.

***H. erectus* (c. 1.9 Ma):**

• Acheulean hand-axes required planning and teaching.
• Meat and, later, cooked food supplied energy for a larger brain, while teeth and gut became smaller (Aiello and Wheeler's "expensive tissue" hypothesis; Wrangham's cooking hypothesis). Controlled fire is known from about 1 Ma.
• Longer childhood and shared care of infants followed, since big-brained infants needed years of provisioning and learning.
• Language and symbolism: language allowed cumulative culture, and selection in turn favoured the neural and vocal-tract changes that support it. The FOXP2 gene is involved in speech but is not a "language gene" on its own. Ochre engravings at Blombos Cave (c. 75 ka) and rock art such as Bhimbetka in India show symbolic behaviour.

Recent examples of culture driving genetic change

• Lactase persistence: dairying selected for variants that keep lactase active in adults, in Europe and among East African and South Asian pastoralists.
• Sickle-cell trait: Frank Livingstone (1958) showed that yam cultivation in West Africa cleared forest, created standing water and spread malaria. That raised the frequency of the HbS allele, which protects carriers.
• Starch digestion: populations with starch-rich diets carry more copies of the salivary amylase gene AMY1.
• High altitude: Tibetans carry an EPAS1 variant, inherited from Denisovans, that limits dangerous rises in haemoglobin at altitude. The 2025 identification of the Harbin cranium as Denisovan, from proteins and ancient DNA, gave this archaic population a face.

Indian evidence. At Attirampakkam in Tamil Nadu, Acheulean tools date to about 1.5 Ma, and a Middle Palaeolithic industry appears about 385,000 years ago. Microliths and rock art at Bhimbetka show later cultural complexity. The small stature of the Andamanese is often discussed as an adaptation to tropical forest and island life, but its causes (heat, nutrition, life history) remain debated.

Critical evaluation

• Buffering: culture can shield humans from selection. Clothing, shelter and medicine relax some pressures, while agriculture, crowding and domestic animals created new ones, such as epidemic disease.
• Culture is not genes: it is transmitted differently (horizontally, and it can be deliberately changed). Critics of "meme" analogies warn against treating cultural traits like genes.
• Misuse: biocultural arguments have been misused to rank populations. Most human variation lies within groups, not between them.

Human evolution is therefore best understood as a feedback loop. Culture set the conditions of selection, and the resulting biology enlarged the capacity for culture.