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The Western Ghats run down India's west coast, and your NCERT book names them as one of the world's biodiversity hotspots. Who decides how such a place should be used, and on what evidence? For decades one of the most prominent scientific voices on that question was Madhav Gadgil. Here is who he was, three ideas from his work, a small worked model, and what you can learn from how he worked.
Who was Madhav Gadgil?
The Tyler Prize page for Madhav Gadgil says he was born on 24 May 1942 in Pune, trained at Harvard in mathematical ecology, and won the Tyler Prize for Environmental Achievement in 2015. It notes that his research influenced India's national biodiversity law.
An obituary by economist Gopal Kadekodi in the journal Ecology, Economy and Society (January 2026) records that Gadgil founded the Centre for Ecological Sciences at the Indian Institute of Science, Bengaluru, received the Padma Bhushan in 2006 and the UN Environment Programme's Champions of the Earth award in 2024, and served on the National Tiger Conservation Authority from 2006 to 2009. It states that he died in Pune on the night of 7 January 2026, aged 83.
Idea 1: How much energy should an organism put into breeding?
One of Gadgil's early papers, written with William Bossert, was Life Historical Consequences of Natural Selection (1970). Its starting point is that any organism has limited resources, split between reproduction and everything else. More effort on breeding now means better reproduction now, but lower survival and growth later. Natural selection should adjust that effort at each age to maximise lifetime fitness. Depending on the shape of the costs and benefits, the optimal strategy may be to breed many times, or to breed once in a single all-out effort, "like a salmon".
This is exactly the idea in Section 11.1.3, Life History Variation, of NCERT Class 12 Biology, Chapter 11: "Some organisms breed only once in their lifetime (Pacific salmon fish, bamboo) while others breed many times during their lifetime (most birds and mammals)."
A worked model: breed once or breed many times?
These are made-up classroom numbers, not data from the paper, and the 1970 model is far more detailed.
Animal A breeds once, producing 1,000 eggs, then dies. Animal B produces 200 eggs a year, and each year it has a probability s of surviving to breed again.
Expected lifetime eggs for B = 200 × (1 + s + s² + s³ + ...) = 200 / (1 − s).
If s = 0.8: 200 / 0.2 = 1,000 eggs. A tie with A.
If s = 0.9: 200 / 0.1 = 2,000 eggs. Breeding many times wins.
If s = 0.6: 200 / 0.4 = 500 eggs. Breeding once wins.
The lesson matches the paper's logic: when life after breeding is risky, putting everything into one effort pays. A common mistake is to compare only one year's eggs (1,000 against 200) and forget the survival series.
Idea 2: Why do sacred groves matter?
In 1976 Gadgil and V. D. Vartak published The sacred groves of Western Ghats in India in Economic Botany. Sacred groves are patches of forest protected by local religious tradition. Your NCERT Class 12 chapter on Biodiversity and Conservation lists them in the Western Ghat regions of Karnataka and Maharashtra, among other places, and says that in Meghalaya they are "the last refuges for a large number of rare and threatened plants". Sacred groves and hotspots both appear in Unit 10 of the NEET (UG) 2026 syllabus; check the bulletin for your own exam year.
Idea 3: What did the Western Ghats panel recommend?
Kadekodi's obituary summarises the Western Ghats Ecology Expert Panel, which Gadgil chaired in 2010 to 2011:
It divided the Ghats into three grades of ecologically sensitive zones, based on ecological importance, hazard risk, biodiversity and watershed integrity.
It estimated that about 64% of the Western Ghats, across 6 states, 44 districts and 142 taluks, should fall in these zones.
In the most sensitive zone it recommended stopping almost all new mining, quarrying, thermal power plants, red-category industries and large dams.
It proposed governance from the bottom up, through gram sabhas and local biodiversity management committees, and a Western Ghats Ecology Authority.
The report was politically resisted and diluted, and a separate working group chaired by K. Kasturirangan reported in 2013. Kadekodi also describes Gadgil's support for People's Biodiversity Registers, which put records of local ecological knowledge in the hands of village communities rather than distant offices.
The NCERT chapter explains why the Ghats deserve this attention: they are part of the "Western Ghats and Sri Lanka" hotspot, and they have greater amphibian species diversity than the Eastern Ghats. For the origin of the hotspot idea, read our post on Norman Myers and biodiversity hotspots.
What can a student take from how Gadgil worked?
Use maths in biology. His early work turned a question about salmon and birds into a model of costs and benefits.
Look at what is already working. Sacred groves were conservation that communities had practised for generations. He studied them rather than ignoring them.
Be clear about trade-offs. Every recommendation of the panel is a choice between uses of land. Naming the costs openly is part of the science.
If the population ideas in Chapter 11 feel abstract, the Fermi Concept Library covers every concept in biology with its own lesson, so you can review one idea at a time.
Next step: redo the worked model with 300 eggs a year and find the survival probability at which the two strategies tie.
