Sunday, March 27, 2016

Intelligence: How can we make memorization more fun?


First, let's examine the question's premise a bit. Should memorization be fun and is fun generalizable? For e.g., bungee jumping is surely fun for some but unlikely to be fun for someone deathly scared of heights. Another related issue is whether making memorization fun makes it more effective. After all, when the outcome, i.e., the study subject, is inherently uninteresting to a pupil, there's only so much that process could contribute. Any number of mnemonic tools, tricks and now even apps like Memrise (1, 2) claim to have cracked the code for effective memorization. However, an age-old tradition steeped in hidebound conservatism and which has remained seemingly unchanged for thousands of years probably has them all beat when it comes to 1) effectiveness, 2) absence of fun, and 3) applicability to everyone, not just those innately endowed with superior memory abilities.

Non-fun memorization can be exceptionally effective
Wouldn't an unbroken oral memorization tradition conservatively estimated to have lasted ~3000 years suggest exceptional effectiveness? Rote memorization involving elaborate mnemonic techniques, Vedic chant, including traditional face-to-face oral training, this cultural peculiarity of the Indian sub-continent provides durable, empirical data that memorization needn't be fun to be effective and long-lasting.
Conservatively estimated to have originated in the Late Bronze Age to the Iron Age India, the Vedas have been passed down for ~3000 years in an unbroken tradition, largely orally in the initial millenia.
What's this memorization process? Starting at a young age, typically between 9 and 12 years of age, children, mainly boys, train in memorizing Vedic texts daily for 8 to 10 hours for ~ 7 years in Vedic Patashalas (Vedic Pandit Training Schools). Each of these texts contains 40,000 to 100,000 words apiece. The process involves learning the exact intonation and accompanying hand gestures. In this manner, the initial 7 years of training totals ~20,000 hours.

Effective, nay stupendous, non-fun memorization is possible even without pre-selection for innate memory ability
All well and good but what makes this rote memorization process even more compelling is participants aren't selected using any selection process or entrance exam that tests for innate memory or recitation abilities. For example, in a 2015 peer-reviewed study (3) published in the journal NeuroImage, none of the trainee Pandits tested came from 'traditional family lineages of reciters'. Even more remarkable, the Vedic Patashala dropout rate is reportedly a low 5%.

The study (3), a collaboration between the Center for Mind/Brain Sciences, University of Trento, Italy, and the National Brain Research Centre, Haryana, India, 'conducted structural analysis of gray matter density, cortical thickness, local gyrification, and white matter structure, relative to matched controls', and 'found massive gray matter density and cortical thickness increases in Pandit brains in language, memory and visual systems, including i) bilateral lateral temporal cortices and ii) the anterior cingulate cortex and the hippocampus, regions associated with long and short-term memory’ (3).
Albeit in the narrow sphere of rote memorization of extremely specialized material, the continuing existence of both process (a specific oral learning tradition) and product (the Vedas) is proof positive that this training system's very effective. All the more remarkable considering it's survived the entire gamut of historical vagaries, wars, invasions, famines, colonization and the like. As the authors of the study (3) state, 'while the ability of Yajurveda Pandits to perform large-scale, precise oral memorization and recitation of Vedic Sanskrit texts may, prima facie, appear extraordinary or bordering on impossible, textual memorization and recitation are in fact standard practice in traditional Sanskrit education in India...while the Pandit's memorization capacity may appear unique to graduates of a Western educational system, it is one of several memorization-related study traditions current in the Indian subcontinent'.

What could explain the success of such a presumably non-fun memorization program?
1) A group activity (see picture below from 5), i.e., shared commitment and sacrifice of time and effort, may help better engage the mind in the learning process.
2) Discipline and practice as in every day for several hours per day. In this regard, the process is uncannily similar to the process of spatial memorization techniques revealed in the famous London Taxi Driver study (4), which found the phenomenal memorization capacity of the archetypal London taxi driver involved learning not just expert spatial navigation but also 'rote memorization of a large volume of preset verbal sequences' (3), i.e., ~30,000 street and place names 'in 320 set sequences totaling ~120,000 words, with part-time training over ~3 to 5 years' (3). In fact, the 2015 Vedic Pandit trainee study (3) found similar hippocampal differences to those reported in the London taxi driver study, i.e., generalizable memorization principles are at work in two different processes, textual versus textual-spatial, in two different cultures.
3) The student's not alone. His teacher, the guru, is equally invested in the student's learning. Let's recall this is an oral learning tradition. It requires Guru-Shishya (teacher-student) face-to-face training.
4) Continuous practice. Once trained, most students go on to become either Vedic teachers themselves or priests.  In any case, they continue at least ~3 hours of daily recitation. This continuing practice ensures memorized material's retained over time.

This memorization system offers some general principles for effective memorization, namely, having a partner/partners who participate(s) in the learning process, and more importantly a teacher who's evidently heavily invested in the student's learning, and regular practice, something that requires discipline more than fun. The former, having a partner, may be helpful for topics/subjects engaging little by way of innate interest, for e.g., memorizing just for tests and exams.

More importantly, given its unbroken lineage of thousands of years and therefore unparalleled success in rote memorization, the Vedic memorization process offers the world a unique test-bed. Modern scientific investigation should research it to deconstruct its processes and thereby make its general memorization principles and practices available for the benefit of all.

Bibliography
1. BBC News, David Robson, May 1, 2015. How to supercharge the way you learn
2. BBC News, David Robson, March 7, 2014. How to learn like a memory champion
3. Hartzell, James F., et al. "Brains of verbal memory specialists show anatomical differences in language, memory and visual systems." NeuroImage (2015). http://ac.els-cdn.com/S105381191...
4. Maguire, Eleanor A., et al. "Navigation-related structural change in the hippocampi of taxi drivers." Proceedings of the National Academy of Sciences 97.8 (2000): 4398-4403. http://www.pnas.org/content/97/8...
5. The Hindu, Suganthy Krishnamachari. October 8, 2015. http://www.thehindu.com/features...


https://www.quora.com/Intelligence/How-can-we-make-memorization-more-fun/answer/Tirumalai-Kamala


Sunday, March 20, 2016

How economically advanced are the slums in India? What kinds of products do they produce?


'How economically advanced are the slums in India?'
Advanced is a loaded word in general and especially so in the context of slums. Generally, we're taught to denigrate slums and look down on people who live there. The truth is, in the face of both governmental inertia and societal apathy, slums develop out of necessity and are a veritable bee-hive of economic activity and resourcefulness, the likes of which are unprecedented in all other social strata and endeavors. Not only that, over time, the economic activity of slums becomes the very life blood of not only cities in which they exist but through the inexorable process of globalization, its tentacles feed every part of global economic activity. Nowhere is this truism clearer than in Dharavi, the sprawling slum at the heart of Mumbai, India's most populous city, and its financial and entertainment capital.
Dharavi's location: very economically advanced
  • To its north, the Mahim-Sion link road
  • To its south-west, the central railway line
  • To its south, the western railway line
  • Close proximity to Mumbai's newest, swankiest business district, the Bandra Kurla Complex.
  • Thus, Dharavi is surrounded by 4 railway stations, several bus-lines, and is close to both international and domestic airports of Mumbai (1).
  • Location-wise it doesn't get better than this (see figures below from 2, 3, 4), especially for swamp land that a little more than a century back was deemed worthless, and thus ignored and neglected by governments.
  • Total area? ~550 acres (~175 hectares), i.e., smaller than New York's Central Park, but with an estimated, astounding density of ~18000 people per acre in some areas, i.e., 6 to 8X more dense than Manhattan.
  • Even densities of up to 336, 643 have been measured in some areas of Dharavi (5).


A very brief history of Dharavi explains why its location is now so economically advanced
  • Predating the current city of Mumbai, in the late 17th century, local Koli fishermen lived in the swamp lands near the Mithi River.
  • Recognizing the great potential of a natural harbor, in 1534 the Portuguese captured seven separate islands, the as-yet-non-existent Mumbai, which became a wedding gift to England's Charles II in 1662.
  • Promising 'free settlement, freedom of religion and unregulated trade', the British East India Company encouraged internal migration to stock the growing city with the labor necessary to feed its global trade from this vital port city (1).
  • Starting in the 1800s, the city of Mumbai began reclaiming land to accommodate its increasing population. Over time, the reclaimed land in the swampy areas near Mahim river became Dharavi (3).
  • The government back then considered Dharavi unfit for inhabitation.
  • Swamp land near-impossible to build on, inconveniently far from the then city center, deemed of no interest.
  • For a century, impoverished migrants from all over India seeking economic opportunity in the booming port city had little choice but to settle in places like Dharavi.
  • It was 'unregulated, available and free of cost' (1).
  • As the city of Mumbai grew further north from its southern base, communities labeled undesirable were forcibly evicted to the then city edges, i.e., nearer to Dharavi.
  • The impoverished migrants provided a ready supply of cheap labor and conveniently in return, the city, government, employers needed to provide little in terms of services.
  • Not housing, not stable employment, nor health care, let alone investment in terms of insurance and pensions.
  • New migrants and the original inhabitants, the Kolis, developed the land themselves, without any government support.
  • Over time, families and relatives of pioneer migrants came to settle and Dharavi's population grew in distinct patterns of caste, religion and occupation.
  • As the then city proper South Mumbai boomed, those unable to afford housing there also gravitated towards Dharavi.
  • Historically, the colonial overlords lived in the wealthier South Mumbai and that old class divide still brands the city even as it consumes its neighboring environs in its insatiable appetite for growth (see figure below from 6).
  • In the process and over time, Mumbai's growth around and beyond the previously shunned and derided Dharavi has today made it one of the most monetarily valuable and coveted real estates in the world.
  • Eventually, with the city council being forced to recognize Dharavi as part of Mumbai's central municipality (7), a few public toilets and water taps were installed.
  • With this denominational change, Dharavi residents earned at least a modicum of respect.
  • Estimated anywhere from half a million to a million in number, they'd become important vote banks for local politicians.
  • Ever since, they exist in a constant tussle between their original no man's land identity limned in sheer pluck and ingenuity, and the western-oriented dreams of politicians, city planners and Mumbai's middle class who aspire to live in a 'world-class' city, whatever that means.
  • Already there's a pattern to note. Cities attract two types of migrants, those considered desirable and the rest, undesirable.
  • The former tend to be the affluent or middle class while the latter are typically the rural impoverished who leave ancestral homes for better economic opportunities in cities, often in desperation.
  • Historically, cities and their governments didn't care about the latter migrants so didn't prepare for them, welcome them or even accommodate them in a civilized and methodical manner.
  • Dharavi serves as a convenient poster-child for this process. Today comprising ~80 neighborhoods, ~1 million inhabitants and ~100,000 microenterprises, migrants living there include potters from Gujarat, leather tanners from Tamil Nadu, embroidery specialists from Uttar Pradesh, and many others.
  • By and large, they are either Muslims or Hindu lower castes including the so-called untouchables.
  • They may have left their ancestral land behind but they brought with them the specialized knowledge pertaining to family trades, culture and practices. These formed the bedrock of Dharavi's economic activity.
  • Sign of chameleon-like adaptability, today recycling is one of Dharavi's major economic activities.
  • Unencumbered with environmental, factory or labor regulations makes Dharavi's labor and production costs low, at the expense of health, safety and longevity.
  • Current cottage industries in Dharavi include large-scale recycling, leather tanneries, metal work, wood work, machinery manufacturing, printing, garment finishing, and shoe, luggage and jewelry manufacture (8).

'What kinds of products do they produce?'

Dharavi's recycling business

Dharavi is estimated to recycle ~80% of Mumbai's plastic, numbers estimated to be far higher than those in the UK (9; see figures below from 4, 10, 11). As the world's ninth most populous city, this is no mean feat.


Dharavi's potteries (figures from 11, 12, 13, 14).

From hand embroidery to leather goods to goat intestines that will eventually end up as surgical thread (see figures below from 4, 11, 15), Dharavi's economy is complex, mulifaceted, just like the migrants who've made it their home.

Dharavi is already organically exporting its microenterprise, mixed-use space economic model to other slums


Dharavi's staggering complexity, ingenuity and industriousness begs the question, what's a slum?
 
What is a slum?

Apparently, the word slum was first used to describe dense, impoverished and unsanitary housing of 1820s London (16). The UN's attempt to define slum, 'Slums are neglected parts of cities where housing and living conditions are appallingly poor. Slums range from high-density, squalid central city tenements to spontaneous squatter settlements without legal recognition or rights, sprawling at the edge of cities' leaves much to be desired and unsatisfactory when applied to Dharavi. A more detailed attempt captures key slum attributes, with the worst ones having all of them (16):
  • 'Lack of basic services: Inadequate access to safe water sources and sanitation facilities is the most significant feature. It is sometimes supplemented by absence of electricity, waste collection systems, surfaced roads, rainwater drainage and street lighting.
  • Substandard housing or illegal and inadequate building structures: Houses are often constructed with non-permanent materials. Given local conditions concerning climate and location, these materials may be unsuitable for housing.
  • Overcrowding and high density: A majority of the slum dwelling units suffer from high occupancy and the living space per inhabitant is scarce.
  • Unhealthy living conditions and hazardous locations: Due to lack of basic services, such as sewage, waste and pollution management, unhealthy living conditions occur. Buildings may also be constructed on hazardous or unsuitable land.
  • Insecure tenure: Lack of formal documents entitling settlers to occupy land bring about an insecurity in residential status.
  • Poverty and social exclusion: As a cause and consequence of slum conditions; income and capability poverty restrain human and economical development.
  • Minimum settlement size: A single household cannot be referred to as a slum since the term constitutes a precinct.'
Is Dharavi a slum?
  • Strictly using the UN's more detailed yardstick, no doubt Dharavi is a slum (see figure from 17 on the left). But the reality is far more nuanced and murky.
  • Even a straightforward survey of Dharavi's inhabitants puts paid to the notion of ranks of the desperately impoverished belonging to the lowest rungs of society.
  • As Mumbai grew upward, around and beyond Dharavi, reaching out to and encompassing its  erstwhile suburbs, its perennial, desperate housing shortage drove new waves of Dharavi migrants, from blue collar workers like carpenters and electricians to white collar workers such as engineers, graphic designers and even those in the civil service such as clerks and police, all pulled to Dharavi by a common thread, affordable housing (see figure below from 18 on the right).
  • For example, a study showed that 'in Mumbai in May 2006 we had 4,426 Police Constables (13 more than there were a year earlier) and 81 Police Inspectors living in slums: officers of the law who are illegal residents of the city' (14).
  • According to Krishna Pujari, who organizes a controversial slum tour through Dharavi, 'All sorts of people live in Dharavi. MNC [multinational corporation] workers, BPO [business process outsourcing] workers, 60 percent of our police force' (10).

In Dharavi, lack of modern amenities equals lack of basic dignity
  • Lack of proper water supply, sewage systems, toilet facilities makes cholera, malaria, typhoid, dengue common in Dharavi.
  • Unregulated, toxic industries (tanneries, paints, plastic recycling) further contribute to chronic diseases.
  • In Dharavi's leather accessories manufacture, 15 to 17 hour days are common, including 2 to 3 hour breaks for lunch and dinner. Only ~1% of these enterprises and workers have access to on-premise toilet facilities (8).
  • Such callousness reveals an unpleasant though essential truth. Querying the use of the word slum is far from an exercise in semantics. It holds a mirror to our values. Inconsiderate, superficial, unthinking, uncaring? Sure, slum’s fine. Introspect and probe? Slum’s revealed as yet another way to shun and otherize.
  • By now, copious news coverage and sociological research confirms that, lack of public or private investment notwithstanding, Dharavi generates valuable economic output for Mumbai and beyond.
In terms of its economic output, quite unlike modern, organized labor with entrenched long commutes and other environmentally unsustainable practices such as high-rise sleeper/bedroom communities, strip malls, colossal car showrooms, etc, it's not just a question of what but also how.
  • Much of Dharavi is mixed-use space, i.e., living and working quarters cheek by jowl.
  • Small-scale microenterprises, with most businesses employing 20 or less.
  • The recycling aspect of Dharavi's economy makes it even more avant-garde.
  • Whatever is intended by the use of the phrase 'economically advanced', Dharavi far outpaces conventional notions of sustainable economic development.
  • Enlightened politicians and city planners, if such species do exist, could see in this aspect of Dharavi an economy of the future, the much-vaunted, eminently desirable Circular economy.
  • Desirable because other than abandoning a wantonly destroyed Mother Earth to take to permanent space stations or colonizing Mars or some such science fiction fantasy a la WALL-E, sustainable economic development is the only way out for humans and for Mother Earth.
  • From such a perspective, instead of looking to teach down to, Dharavi becomes a place to learn from.
  • A natural experiment in urbanology, what Dharavi lacks is the modicum of dignity that non-slum dwellers take for granted, clean running water at home, hygienic sewage drainage, indoor toilets, basic health care, job safety and security, and regulated pay.
  • As for what it takes to make a sustainable living-working space in the 21st century, Dharavi's natural experiment already points us the way ahead. If that isn't economically advanced, I don't know what is.

Bibliography
  1. Page on bekon.lth.se
  2. Eriksson, Charlotta. "Dharavi: Space, time, human condition towards a theory on unplanned settlements." (2013). http://www.diva-portal.org/smash...
  3. Page on artdurnev.com
  4. Page on yimg.com
  5. Echanove, Matias, and Rahul Srivastava. "The High-Rise and the Slum: Speculative Urban Development in Mumbai." (2012): 789-813. Page on berkeley.edu
  6. Mumbai case study
  7. Engqvist, Jonatan Habib, and Maria Lantz. Dharavi: documenting informalities. Royal University College of Fine Arts, 2008.
  8. Page on nceuis.nic.in
  9. Waste not, want not in the £700m slum
  10. 404 page - Motherland Magazine
  11. National Geographic Magazine - NGM.com
  12. Page on comm-dev.org
  13. Megha Gupta's Dharavimarket.com aims to sell products by Dharavi's craftspeople across the world - The Economic Times
  14. Page on udri.org
  15. http://kaustuv.net/projects/MIRG...
  16. http://mirror.unhabitat.org/pmss...
  17. Dyson, Peter. "Slum tourism: representing and interpreting ‘reality’ in Dharavi, Mumbai." Tourism Geographies 14.2 (2012): 254-274.
  18. Larsson, Emma, and Maja Nilsson. "Towards sustainable sanitation in slum areas: A field study in Mumbai." (2013). http://www.diva-portal.org/smash...



https://www.quora.com/How-economically-advanced-are-the-slums-in-India-What-kinds-of-products-do-they-produce/answer/Tirumalai-Kamala


Sunday, March 13, 2016

When was inbreeding historically understood to cause defects in offspring?

  • This is one of those tricky subjects where on the one hand, it would seem that clear, compelling scientific evidence would be readily available, and, OTOH, entrenched societal stigma makes human inbreeding a particularly thorny subject for methodical, scientifically rigorous studies. In short, it's not that data is surprisingly hard to find. Rather, rigorously and appropriately controlled studies are hard to come by.
  • It's also important to parse human inbreeding into socially acceptable versus unacceptable. Socially acceptable? Marriages between cousins and uncles-nieces are common, indeed preferred, in many parts of the world, viz., North and sub-Saharan Africa, the Middle East, Central and South Asia (1, 2; see figure below for estimates).


Unsurprisingly, data on the socially acceptable form of inbreeding is more voluminous.
  • For e.g., first-cousin marriages and marriages between girls and their maternal uncles are longstanding traditions in South India (the states of Andhra Pradesh, Karnataka, Tamil Nadu, Telangana) (3, 4, 5). 
  • In the US, state level control determines whether first cousin marriages are legal or not, with criminal and civil sanctions in 8 and 22 states, respectively  (see figure below from 6; also 7, 8).
  • OTOH, Europe has largely left consanguineous unions unlegislated.


In Written Historical Record
  • In both Plato's Laws (dialogue) (9) and Xenophon's Memorabilia (Xenophon) (10), Socrates is quoted to mention 'unwritten laws' legislated by the gods. These laws couldn't be disobeyed without natural penalties.
  • Socrates describes the incest taboo as one of these unwritten laws since it had a greater likelihood of producing defective offspring.
  • Problem is these treatises don't mention why the taboo arose in the first place, i.e., no observed data on health of offspring from incestuous unions compared to non-incestuous ones.

Physical Evidence from Archaeology and Historical Census data
  • Early 20th century genealogies of the 18th and 19th dynasty Egyptian kings (pre-332 B.C.) are unhelpful since they show 
    • No evidence of reduced reproductive capacity.
    • Little/no recorded proof of physical or possible mental defects in the mummies of royal brother-sister offspring (11).
  • OTOH, in Roman Egypt, 19.6% and 3.9% of marriages in the city of Arsinoe were between brother-sister and siblings, respectively (12). This data comes from the census of Egypt held every 14 years during Roman rule. Each household was required to file a return listing all its members, their names, ages and kinship affiliation. While only a tiny fraction of the millions of papyrus census filings have survived, 300 have been published and subjected to demographic analysis.
  • Pharoaonic Egypt believed that brother-sister unions strengthened the royal bloodline.
  • Recent research reveals incest occurred outside the ruling classes as well (13, 14).
  • These historical data don't support the idea that prehistoric or historic human may have observed greater birth defects from inbreeding and thereby instituted incest taboo as a cultural norm.

Edvard Westermarck: first hailed then ridiculed and now, a century later, finally vindicated?
The beginning, 1890 -1921.
  • In Europe and North America, first-cousin marriages were commonplace until the mid-19th century.
  • Starting in the 1850s, scientists and physicians in Europe and North America began to debate the biological effects of close kin marriage (15). 
  • Charles Darwin's marriage to his 1st cousin, Emma Wedgwood, yielded 10 children. By lobbying Sir John Lubbock, he tried to persuade the Parliament of Great Britain and Ireland that the 1871 census should assess the prevalence of 1st cousin marriages. Unsurprisingly, his argument was predicated on sound science, 'When the principles of breeding and of inheritance are better understood, we shall not hear ignorant members of our legislature rejecting with scorn a plan for ascertaining by an easy method whether or not consanguineous marriages are injurious to man' (16). After all, we need robust data before we can conclude benefit or harm of a practice, don't we?
  • However, the culture of the time prevailed against any such effort. The stated objections are telling signposts of the profound difficulty in inculcating scientific temper in society, a difficulty that stubbornly persists to this day.
  • For example, one committee member, Gathorne Hardy stated, 'he did not see the desirability of holding up families where such marriages had taken place, and the children being anatomised for the benefit of science' (17).
  • A generation later, Darwin's son G.H. Darwin managed to extract such data anyway by cleverly performing surname analysis to assess prevalence of first-cousin marriages (18, 19).
  • Then in 1889, Finnish sociologist Edvard Westermarck became internationally famous when he published his colossal 3-volume survey, The History of Human Marriage.
  • Analyzing the biological data available at that time, he concluded that inbreeding produced high rates of infant mortality, and mental and physical defects (20).
  • Westermarck argued that harmful consequences of inbreeding selected for an innate aversion to sex with childhood associates.
  • Thus, for Westermarck, observed harms of incest didn't create the cultural taboo against incest.
  • Rather, natural selection naturally and inextricably linked the two.
  • In modern re-telling, cohabitation during formative years creates mutual de-eroticization in co-socialized children. In simpler words, growing up together inculcates sexual aversion.

The barren years, 1934-1962.
  • Shockingly, from the turn of the 20th century until the 1960s, Westermarck's ideas were actively derided and shunned by a literal who's who of 20th century biology, anthropology and psychology. This, even though early supporters of his ideas included the likes of Edward Burnett Tylor and Alfred Russel Wallace.
  • Problem for Westermarck was that he wasn't only a Darwinian but also a steadfast empiricist. Thus, for him incest's biology, psychology and culture were inseparable.
  • In the first instance, many simply didn't believe that close inbreeding was harmful.
    • Lord Raglan accused Westermarck of arguing inbreeding is harmful 'in the face of all the evidence' (21).
    • Bronisław Malinowski argued 'biologists are in agreement that there is no detrimental effect produced upon the species by incestuous unions' (22).
    • Robert Briffault wrote 'there is not in the records of breeding from domesticated animals a single fact . . . which indicates, much less evidences, that inbreeding, even the closest, is itself productive of evil effects' (23).
    • The final nail in Westermarck's coffin came from Sigmund Freud. In an essay titled Totem and Taboo (1910), Freud challenged the Westermarck hypothesis saying, 'the earliest sexual excitations of youthful human beings are invariably of an incestuous character'. He thus argued that the incest taboo only existed to keep this natural propensity at bay.
    • Later luminaries such as Leslie White in 1949, Claude Lévi-Strauss in 1950 and David Aberle in 1956 continued denying that close inbreeding is injurious.
  • Second, through much of the 20th century, Westermarck's ideas were actively shunned in favor of those advocated by Freud and Levi-Strauss, i.e., that humans lacked sexual imprinting so cultural taboo of incest became necessary.
    • Coined by Konrad Lorenz, sexual imprinting is the notion that many animal species avoid mating with close kin such as siblings.
    • In other words, the prevailing Freudian idea implied that a priori early human developed cultural taboo around incest based on rational observation of its harmful effects, i.e., greater chances of defective offspring.
    • It's interesting to speculate why Freud's take on the reason for the incest taboo prevailed for almost a century. Hill Gates claims (24) it's due to anthropology's 'embrace... of Freud's Oedipus complex', i.e., the narrative that humans need to repress their selfish sexual desires to fully realize their potential.
    • In other words, our need to believe, contrary to copious evidence, that our rationality triumphs. Against such a dramatic narrative arc, what chance for Westermarck's hypothesis that early life association inhibits sexual attraction? After all, it's positively anticlimactic. 
  • Problem is the Freudian idea prevailed in absence, not because, of incontrovertible scientific evidence.

The tide reverses, 1962-Present.
  • Starting in the 1960s, a slow tide of studies revived Westermarck's ideas for two reasons,
  • One, studies showed close inbreeding is injurious.
      • For e.g., studies from Norway (25), Turkey (26), Israel (27), Pakistan (28) showed that compared to unrelated parents, children of first cousins had twice the population baseline probability of congenital malformation and/or genetic diseases.
  • Two, sexual imprinting exists in humans. Now called the Westermarck effect.
    • In 1962, Robin Fox wrote that the notion of sex among people who'd experienced close bodily contact as children ranged from disgusting to unthinkable to indifferent (29).
    • In 1964, Yonina Talmon studied sexual relations among community-reared children in two Israeli Kibbutz. Neither biologically related nor denied permission to marry, nonetheless, they didn't do so because they didn't feel sexual attraction towards one another (30). Joseph Shepher's 1971 follow-up study (31) confirmed Talmon's findings. 
  • In turn-of-20th century Taiwan, 3 types of marriages were practiced.
      • In 'major marriage', the bride and groom's parents arranged the marriage, and typically bride and groom didn't meet until the day of marriage.
      • In 'uxorilocal marriage', the groom and bride's parents arranged the marriage, typically bride and groom didn't meet until the day of marriage, and the couple lived with the wife's family.
      • In 'minor marriage', the sim-pua (little bride), aged from a few days of age to 4 years old, was betrothed in infancy and raised with her future husband in his house. Post-puberty, they were married (saq-cue-tui or 'pushing together') in their mid-teens. 
    • Westermarck's hypothesis would predict that early association would create sexual aversion, despite the prevailing cultural norm.
    • Indeed, the Stanford anthropologist, Arthur Wolf, found minor marriage couples had much higher divorce and adultery rates, and fewer children per year (32).
    • Taking advantage of the meticulous demographic records the Japanese government kept during their occupation of Taiwan between 1895 and 1945, Wolf collected and analyzed the adoptions, births, deaths, divorces and marriages among the island's inhabitants, i.e., data on >14000 women from 26 villages and 2 towns.
    • Using fertility, divorces and extramarital affairs as proxies for sexual inhibition and aversion, he found that extramarital affairs were 16.5% for women whose marriages were arranged by their and the groom's parents but 37.7% for women from minor marriages.
    • Wolf was also able to rule out competing hypotheses such as health disparities between women in minor versus arranged marriages.
Data from Incest (copulation with parents, offspring, siblings)
  • Problem is two-fold
    • Few studies exist (see figure below from 6 using data adapted from 33).
    • They're plagued with design flaws that engender confirmation bias and thus preclude firm conclusions about the data. These include
      • Incestuous mothers tend to be very young; published studies didn't/couldn't adequately control for that.
      • Incest group typically comprises greater physical and mental handicaps.
      • For e.g., the 1971 Czech study by Seemanova (see table below) had 141 females in the incestuous group. Of these, 20 were intellectually handicapped and, in addition, 2 each were deaf-mutes, had congenital syphilis or were epileptics. In addition, two others were deaf-mutes and three were schizophrenic. OTOH, in the control group of 46 mothers, only 2 were intellectually handicapped (one additionally a deaf-mute), and 2 other deaf-mutes.
      • Same gap exists in the fathers as well. Of 138 fathers in incestuous pairings, 8 intellectually handicapped, 13 chronic alcoholics, 2 with syphilis, and 4 suicides. OTOH, the nonincestuous group of 52 fathers had none who were intellectually handicapped, 2 chronic alcoholics and 1 with polydactyly.
  • OTOH, the data is clearer and cleaner in animal studies.
    • Mother-son incest is rare in Rhesus macaques (34). 
    • Incest is rare in other primates, mammals, birds, amphibians and even insects (35).
    • In fact, incest is uncommon throughout the animal kingdom (36, 37), rare exceptions being eusocial mammals such as naked mole rats (38).
Irony dictates it's appropriate to end with Freud's Oedipus complex.
  • Separated at birth from his mother, Jocasta, Oedipus ends up bolstering rather than demolishing Westermarck's hypothesis.
  • After all, early separation undermines natural adaptation for incest avoidance.
  • More recent government data also supports this idea, again ironically because the goal of the bureaucratic intervention in this instance was something else entirely.
  • In 1975, Britain enacted the Access to Birth Records Act.
  • This Act enables adopted persons >18 years of age to trace their biological kin.
  • Maurice Greenberg and Roland Littlewood studied reunited kin (39).
    • They estimate >50% of reunited kin experience strong sexual feelings.
    • They also suggest incest may be frequent.
  • While there are many similar anecdotal reports in the literature, Anaïs Nin's experience with her father, Joaquín Nin (40), is one of the most famous examples that supports Westermarck's hypothesis that early association (attachment?) is essential in engendering incest aversion.

Also, the all-important caveat: Science hasn't yet uncovered the all-important how as in how early life association and incest aversion mechanistically intersect at the biological (genetic/epigenetic) level, i.e., how genetic selection shapes incest aversion over time and how early life association mediates this effect.

Bibliography
  1. Bittles, Alan Holland. "Empirical estimates of the global prevalence of consanguineous marriage in contemporary societies." (1998). Page on murdoch.edu.au
  2. Bittles A.H. and Black M.L. (2015). Global Patterns & Tables of Consanguinity. Main Page - ConsangWiki - Consang.net
  3. Kapadia, Kanaiyalal Motilal. Marriage and family in India. Bombay: Oxford University Press, 1966, p117-137.
  4. Nilakanta Sastri, K. A. A history of South India from prehistoric times to the fall of Vijayanagara. Delhi, 1975, p66.
  5. Bittles, Alan H., J. Michael Coble, and N. Appaji Rao. "Trends in consanguineous marriage in Karnataka, South India, 1980–89." Journal of biosocial science 25.01 (1993): 111-116.
  6. Chapter 2. Genetic Aspects of Inbreeding and Incest. Alan Bittles. pp. 38-60 in Wolf, Arthur P. Inbreeding, incest, and the incest taboo: The state of knowledge at the turn of the century. Stanford University Press, 2005.
  7. M. Ottenheimer, “Lewis Henry Morgan and the prohibition of cousin marriage in the United States,” Journal of Family History, vol. 15 (1990), pp. 325–34.
  8. M. Ottenheimer, Forbidden Relatives: The American Myth of Cousin Marriage (Urbana: University of Illinois Press, 1996), pp. 19–41.
  9. Plato, Laws, trans. Thomas Pangle (New York: Basic Books, 1980), 838a–39b.
  10. Xenophon, Memorabilia, IV.iv.19–23.
  11. M. A. Ruffer, “On the physical effects of consanguineous marriages in the royal families of Ancient Egypt,” in Studies in the Paleopathology of Egypt, ed. L. R. Moodie (Chicago: University of Chicago Press, 1922), pp. 322–66.
  12. Scheidel, Walter. "Brother-sister marriage in Roman Egypt." Journal of biosocial science 29.03 (1997): 361-371. Page on researchgate.net
  13. Hopkins, Keith. "Brother-sister marriage in Roman Egypt." Comparative Studies in Society and History 22.03 (1980): 303-354.
  14. Scheidel, Walter. "Brother-sister and parent-child marriage outside royal families in ancient Egypt and Iran: a challenge to the sociobiological view of incest avoidance?." Ethology and Sociobiology 17.5 (1996): 319-340.
  15. A. H. Bittles, “The basis of Western attitudes towards consanguineous marriage,” Development Medicine and Child Neurology, vol. 45 (2003), pp. 135–38.
  16. C. Darwin, The Descent of Man, vol. 2 (London: John Murray, 1871. p. 403.
  17. HMSO (Her Majesty’s Stationary Office), Parliamentary Debates, Third Series (London: Her Majesty’s Stationary Office, 1870), pp. 1006–10.
  18. G. H. Darwin, “Marriages between first cousins in England and Wales and their effects,” Journal of the Statistical Society, vol. 38 (1875), pp. 153–84.
  19. G. H. Darwin, “Note on the marriage of first cousins,” Journal of the Statistical Society, vol. 38 (1875), pp. 344–48.
  20. Westermarck, Edward. The history of human marriage. Vol. 2. Macmillan, 1921. pp. 224–36.
  21. Lord Raglan, Jocasta’s Crime (London, 1933), p. 16.
  22. Bronislaw Malinowski, Sex and Repression in Savage Society (London,1927), p. 243.
  23. Robert Briffault, The Mothers (London, 1927), vol. 1, p. 215.
  24. Gates, Hill. "Refining the Incest Taboo." Wolf and Durham (2005) 139 (2005): 60.
  25. Stoltenberg, Camilla, et al. "Influence of consanguinity and maternal education on risk of stillbirth and infant death in Norway, 1967–1993." American journal of epidemiology 148.5 (1998): 452-459. Influence of Consanguinity and Maternal Education on Risk of Stillbirth and Infant Death in Norway, 1967-1993
  26. Demirel, S., et al. "The frequency of consanguinity in Konya, Turkey, and its medical effects." Genetic counseling (Geneva, Switzerland) 8.4 (1996): 295-301.
  27. Jaber, Lutfi, et al. "Marked parental consanguinity as a cause for increased major malformations in an Israeli Arab community." American journal of medical genetics 44.1 (1992): 1-6.
  28. Hussain, R. "The impact of consanguinity and inbreeding on perinatal mortality in Karachi, Pakistan." Paediatric and perinatal epidemiology 12.4 (1998): 370-82.
  29. Fox, J. Robin. "Sibling incest." British journal of sociology (1962): 128-150.
  30. Talmon, Yonina. "Mate selection in collective settlements." American Sociological Review (1964): 491-508.
  31. Shepher, Joseph. "Mate selection among second generation kibbutz adolescents and adults: Incest avoidance and negative imprinting." Archives of sexual behavior 1.4 (1971): 293-307.
  32. Wolf, Arthur P. Sexual attraction and childhood association: a Chinese brief for Edward Westermarck. Stanford University Press, 1995.
  33. C O. Carter, “Risk to offspring of incest,” The Lancet, vol. 289 (1967), p. 436.
  34. Sade, Donald Stone. "Inhibition of son-mother mating among free-ranging rhesus monkeys." Science and Psychoanalysis, vol. 12 (1968): 18-38.
  35. Chapter 3. Inbreeding Avoidance in Primates, Anne Pusey, pp.61-75 in Wolf, Arthur P. Inbreeding, incest, and the incest taboo: The state of knowledge at the turn of the century. Stanford University Press, 2005.
  36. Ågren, Greta. "Incest avoidance and bonding between siblings in gerbils." Behavioral Ecology and Sociobiology 14.3 (1984): 161-169.
  37. Gavish, Leah, Joyce E. Hofmann, and Lowell L. Getz. "Sibling recognition in the prairie vole, Microtus ochrogaster." Animal Behaviour 32.2 (1984): 362-366.
  38. Reeve, Hudson K., et al. "DNA" fingerprinting" reveals high levels of inbreeding in colonies of the eusocial naked mole-rat." Proceedings of the National Academy of Sciences 87.7 (1990): 2496-2500. Page on pnas.org
  39. Greenberg, Maurice, and Roland Littlewood. "Post‐adoption incest and phenotypic matching: Experience, personal meanings and biosocial implications." British journal of medical psychology 68.1 (1995): 29-44.
  40. Deirdre Bair, Anaïs Nin: A Biography (New York: Putnam and Sons, 1995.
https://www.quora.com/When-was-inbreeding-historically-understood-to-cause-defects-in-offspring/answer/Tirumalai-Kamala



Sunday, March 6, 2016

Why is anemia a common problem among Indian women?

Short answer, anemia in Indian girls is predicated by both biology and socio-economic factors, i.e., unique confluence of biology, culture (diet, marriage age), and great variations in relative affluence and education.

Early marriage ---> early initiation of sexual activity ---> repeated early child bearing ---> recurrent iron loss. This emerges as a major reason for anemia among Indian girls.

Thus, large part of anemia in Indian girls ensues from exacerbation of their inherently greater risk of iron loss attendant to their biology, i.e., pregnancy, child birth and breast feeding. Such exacerbation is cultural, i.e., tendency for early marriages and child births, as well as dietary, i.e., inadequate iron intake and inefficient absorption.

There are also substantial, surprising and inexplicable regional differences.

While there are several types of anemia, I'll restrict my answer to nutritional anemia, specifically to Iron-Deficiency Anemia (IDA), the most common form of anemia in India (1, 2).

Anemia is assessed by measuring circulating blood hemoglobin levels. Typically, there are 3 levels, Mild (10 to 11.9g/dl), Moderate (7 to 9.9g/dl) and Severe (<7g/dl). Typically, in India, severe anemia prevalence tends to be <3%, moderate ranges from 5 to 20%, and mild from 25 to 44%. So the silver lining is that severe anemia levels are low.

Biological factors that contribute to anemia in Indian girls
  • The most important biological reason for IDA is inadequate dietary intake of bioavailable iron (3; see figure below).
  • There are unique factors associated with Indian diets that may predispose to IDA.
  • Being heavily plant-based, it relies on the less bioavailable non-haem form of iron.
  • Higher levels of Polyphenol and phytates (Phytic acid).
  • Lower ascorbic acid (Vitamin C) to iron ratio which impedes iron absorption.
  • Possible average gastric acidity levels that are sub-optimal for iron absorption.


Inadequate dietary iron intake
  • Dietary iron is available in two forms, haem or non-haem.
  • Haem form of dietary iron is commonly available in meat with the non-haem form in plant foods.
  • Haem iron is much better absorbed so already we arrive at a partial answer to the question.
    • 90 to 95% of total daily dietary iron in Indian diets is non-haem iron (4).
    • Vegetarian diet iron bioavailability is 10% compared to 18% in omnivorous diets.
    • This means Indian diets are richer in the less efficiently absorbed non-haem iron.
  • To compensate for this lower efficiency, nutritionists recommend increasing dietary iron intake by 80% (5).
  • Adding another wrinkle, adequate dietary iron levels does not in and of itself explain India's anemia prevalence since Gujarat with ~23mg/day iron intake still has 55% anemia prevalence compared to Kerala's much lower 33% with just 11mg/day iron intake (4).
  • Thus, inadequate iron intake explains Indian girls' anemia partly, not wholly.
Defective iron absorption
  • More acidic the stomach, better the iron absorption.
    • With the caveat that the same studies didn't compare gastric acidity in India to other countries, an old study found that Indian gastric acidity averages ~3.4, much higher than the average of ~2.5 in other countries (6).
  • Vitamin C (ascorbic acid) is a strong iron absorption enhancer of plant non-haem iron (7). Indian Vitamin C intake tends to be sub-par.
    • In a small (n = 54) 1985 study, vegetarian Indian children with IDA and low vitamin C intake given 100mg Vitamin C during lunch and dinner for 60 days had dramatic improvement, even full recovery from anemia (8).
    • Indian diets tend to have rather low levels of Vitamin C (4, 9).
    • A 2007 study of 214 men and 108 women found sub-optimal Vitamin C intake (recommended 0.4mg/dl) among both (7).
    • Young, married girls in urban Indian slums? Again,  sub-optimal Vitamin C intake (10).
  • Indian diets have several dietary components that bind to bioavailable iron preventing its absorption. These include 
  • Polyphenols. Tea, herb teas, cocoa, coffee, cinnamon, red wine are polyphenol-rich (11).
  • Calcium (12), phosphorus, manganese, zinc.
      • Higher intake of Calcium and Phosphorus correlated with anemia in pregnant women (13).
      • Indians' tendency to drink tea/coffee with meals reduces bioavailability of dietary iron (5).
  • These are all general reasons for IDA in India. Now let's examine the specific reasons for IDA in Indian girls.
  • Here the most pertinent factors are blood loss during menstruation and pregnancies, and loss through breast feeding.
  • Blood loss is perhaps the most important one since iron isn't excreted out through urine or feces but only through loss of cells, skin or blood cells for example. 
  • Age of highest prevalence of IDA in Indian girls, i.e., 12 to 13 years old, coincides with menarche (first menstruation). Two inter-related problems reveal themselves here.
    • One, substantial numbers of Indian girls have menstrual abnormalities but don't seek medical help (14).
    • Two, menstrual blood loss increases daily total iron requirement, consumption of which is sub-optimal for many Indian girls anyway for reasons we've already covered, namely inadequate daily intake and inefficient absorption due to peculiarities associated with Indian diets. Thus, menstruation in Indian girls exacerbates their pre-existing tendency for anemia. 
Socio-economic factors that contribute to anemia in Indian girls
  • The National Family Health Surveys (NFHS) are periodic Indian Government health surveys conducted since 1992-1993.
  • It shows that currently ~27% of Indian girls aged 15 to 19 years are married. This tracks closely with UNICEF data (15). It's also currently one of the highest rates of early marriage in the world.
    • Studies show that married adolescent Indian girls tend to consume diets high in phytates, low in Vitamin C and iron, and unsurpisingly, have high prevalence of IDA (10, 16).
    • In a 2008 study on 118 young, pregnant, poorly educated, low-income Indian girls from North Indian villages, folic acid intakes also tended to be very low (9).
    • On average, Indian women have 297mg of iron loss (blood loss during delivery, iron transfer to newborn, iron content of umbilical cord) versus 150mg of iron conservation (no menstruation) during pregnancy (17). In other words, pregnancy leads to net iron loss. This can only be offset by higher iron intake and absorption.
    • Lactating women obviously have higher daily iron intake requirements, not just to meet infant iron requirement through breast milk but also to make up for loss during pregnancy and delivery.
    • Since daily iron intake requirements are already sub-par in India, deficiency is only exacerbated for pregnant and lactating women.
  • Thus, early marriage ---> early initiation of sexual activity ---> repeated early child bearing ---> recurrent iron loss. This emerges as a major reason for anemia among Indian girls.
  • In other words, large part of anemia in Indian girls ensues from exacerbation of their inherently greater risk of iron loss attendant to their biology, i.e., pregnancy, child birth and breast feeding. Such exacerbation is cultural, i.e., tendency for early marriages and child births, as well as dietary, i.e., inadequate iron intake and inefficient absorption.
  • Several groups have analyzed the Indian Government's NFHS anemia data.
  • Careful data mining of the NFHS and other epidemiological data shows that anemia tends to be higher among women who are illiterate, reside in rural areas, work in agriculture, are Hindu, Scheduled Caste (SC) or Scheduled Tribe (ST) (18, 19, 20).
  • Poorest urban women are also more likely to be anemic compared to everyone else including their rural counterparts (21, 22). Why? Key factors include
    • Lower income, lower access to income and resources.
    • Higher rates of infection due to poor sanitation.
  • Factors found to be protective against anemia
    • Belonging to middle/upper class.
    • Educated up to high school or higher.
    • Consuming alcohol or pulses.
    • Higher BMI (Body Mass Index).
    • Being Muslim.
  • Alcohol consumption protects against anemia, especially among poorer rural women, particularly ST women (21).
    • Surprising? Yes and the underlying biology is still a mystery.
    • A robust literature links alcohol consumption to higher iron levels and absorption (23, 24, 25).
    • Alcohol may increase the fermentation process/gastric acid secretion or promote iron solubility/absorption/ferric ion reduction or could itself be an iron source.
  • Pulses have high iron content and are also a surrogate for higher income.
  • Muslim versus Hindu could be attributed to differences between iron-replete, i.e., non-vegetarian, versus iron-deficient, i.e., vegetarian, diets.
  • On the whole, protective factors clearly suggest that higher income ---> better education ---> better diets ---> lower anemia.
    • In fact, wealth tracks better with iron sufficiency than even education or caste (26).
    • Education comes second (27).
  • One of the most interesting trends is a regional bias in anemia.
    • Anemia prevalence is highest among women in the Eastern states of India (4, 19, 22).
    • Assam, Bihar, Jharkhand, Odisha, West Bengal tend to have the highest women anemia prevalence rates (see figures below from 4 and 19). Why? No clear answer.
    • Anemia in general and IDA in particular is multi-factorial. 
    • Likely answer is some combination of biology and culture, i.e., dietary iron and micronutrient deficiencies, and cultural practices such as early marriages, tendency of less educated women, lower incomes.



  • While there's substantial literature on high anemia prevalence in Indian women, there are fewer such studies in men.
      • In one study on 544 older rural Indian men aged 60 to 84, majority were anemic (28).
      • In fact, Indian men weren't even included in the 1st two NFHS, only being included in the 3rd one (2005-2006) (29).
Anemia rates in Indian women are the highest in the world (3). What could be done to reverse this trend?
  • Centralized approaches would be to co-ordinate and encourage manufacture of fortified foods.
  • This is something that the FAO (Food and Agriculture Organization) also recommends (30).
  • The Micronutrient Initiative began in 2004.
    • Through it, the Tamil Nadu Salt Corporation (TNSC) manufactures double- and triple-fortified salts, Vita-Shakti, fortified with iron and folic acid, and Anuka, fortified with iron, Vitamins A and C (31, 32).
  • As we explored earlier, certain peculiarities of Indian diets easily lead to IDA.
    • Cultural norms are extremely difficult to overcome.
    • Dietary habits are part of such norms.
    • However, there is a silver lining to this conundrum in that several foods that are already part of Indian diets, namely, egg, green vegetables, jaggery, whole wheat, onion stalks, pulses, are iron-rich.
    • Food-based approach is also safer than oral iron supplements which have side-effects such as gastro-intestinal upset (31).
  • Better education of Indian girls will go a long way in alleviating their prevailing anemia levels
    • Would better ensure their conscious and conscientious consumption of iron-rich foods that are already part of Indian diets. So no need to re-invent the wheel in terms of dietary habits.
    • Would encourage their becoming better aware of their basic health parameters such as height, weight, blood type and hemoglobin levels.
    • Would help delay their marriage age.
    • Would help them make better, more empowered decisions regarding childbirth age, spacing between children, and increasing iron, Vitamins A, B12, C, folic acid and riboflavin intake during pregnancy.
Bibliography
  1. Raman, L., A. B. Pawashe, and B. A. Ramalakshmi. "Iron nutritional status of preschool children." The Indian Journal of Pediatrics 59.2 (1992): 209-212.
  2. Yip, Ray. "Iron deficiency: contemporary scientific issues and international programmatic approaches." The Journal of nutrition 124.8 Suppl (1994): 1479S-1490S. Page on nutrition.org
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  4. Nair, K. Madhavan, and Vasuprada Iyengar. "Iron content, bioavailability & factors affecting iron status of Indians." Indian J Med Res 130.5 (2009): 634-45. Page on icmr.nic.in
  5. Rammohan, Anu, Niyi Awofeso, and Marie-Claire Robitaille. "Addressing Female Iron-Deficiency Anaemia in India: Is Vegetarianism the Major Obstacle?." ISRN Public Health 2012 (2011). Page on hindawi.com
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https://www.quora.com/Why-is-anemia-a-common-problem-among-Indian-women/answer/Tirumalai-Kamala