(a) Polygenic Inheritance 10 (b) Prehistoric significance of Rakhigarhi 10 (c) Glottochronology 10 (d) Menopausal symptoms…

(a) Polygenic inheritance

Polygenic inheritance is the control of a trait by many genes at different loci, each with a small, additive effect, along with environment. The trait shows continuous variation and a bell-shaped distribution, with no discrete classes, unlike Mendelian traits. Nilsson-Ehle's wheat grain colour experiments (1909) and Davenport's model of skin colour show it, and Fisher (1918) reconciled it with Mendelism. Human examples are skin colour, stature, intelligence-test scores and blood pressure.

Such traits have high but environment-dependent heritability; stature depends on diet in childhood. Polygenic inheritance shows why there are no sharp racial boundaries, with variation being clinal, and it underlies susceptibility to diabetes and hypertension.

(b) Prehistoric significance of Rakhigarhi

Rakhigarhi, in Hisar district, Haryana, on the Ghaggar–Hakra plain, is among the largest Harappan sites, with several mounds over about 350 hectares or more. Excavations show a sequence from the early (Hakra) phase, through early Harappan to the mature urban phase, with planned streets and drains, mud-brick houses and platforms, craft production of beads, terracotta and shell, seals, weights, and burials.

Its significance is that it shows Harappan origins in the local Hakra culture, and supports continuity of settlement. In 2019 ancient DNA from a female skeleton (Shinde and colleagues) showed ancestry related to Iranian hunter-gatherers and South Asian hunter-gatherers, without Steppe pastoralist or Anatolian farmer ancestry, bearing on debates about Indo-European migration and the peopling of South Asia.

(c) Glottochronology

Glottochronology is a method developed by Morris Swadesh in the 1950s to estimate how long ago related languages diverged, through lexicostatistics. It uses a standard list of basic vocabulary (Swadesh lists of 100 or 200 items) and assumes a constant rate of replacement, about 80–86% of words retained per millennium. The time is t = log C ÷ (2 log r), where C is the proportion of shared cognates and r the retention rate.

It is criticised because rates of change are not constant: borrowing, taboo, contact and social change alter vocabulary, and cognate judgements are subjective (Bergsland and Vogt, 1962). Hence it is considered unreliable, and modern Bayesian phylogenetic methods have largely replaced it.

(d) Menopausal symptoms

Menopause is the permanent end of menstruation, confirmed after 12 months of amenorrhoea, at about 45–55 years, earlier on average in Indian women, due to falling ovarian oestrogen.

Symptoms:

• Vasomotor: hot flushes and night sweats.
• Urogenital: vaginal dryness, dyspareunia and urinary symptoms.
• Psychological: mood change, irritability, insomnia and poor concentration.
• Long-term: bone loss and osteoporosis, and increased cardiovascular risk.

Symptom reporting varies between cultures, with fewer hot flushes reported in some Asian societies, so anthropologists treat menopause as a biocultural event shaped by diet, status and social roles, and not only a disease.

(e) William Ogburn and cultural lag

William Ogburn, in Social Change (1922), proposed cultural lag: material culture (technology) changes faster than non-material culture (customs, laws, values, institutions), and the delay in adjustment causes social problems. Change passes through invention, accumulation, diffusion and adjustment.

Examples are the gap between new technology and cyber law and digital literacy, and between industrial work and old joint-family values. Crime, unemployment and family strain can be seen as products of the lag.

Criticism: the distinction between material and non-material culture is hard to draw, technology is itself shaped by society, and the theory is deterministic. Still, it helps in planning social policy.