Origin of Species

  • Indian researchers have contributed to one of sixty-five major breakthroughs in ecology and evolution over the last 160 years, counted from Charles Darwin’s ‘On the Origin of Species’ in 1859.
  • A study in 2003 from the Evolutionary & Organismal Biology Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), , has been included in a book titled
    • ‘Conceptual Breakthroughs in Evolutionary Ecology’ by Prof. Laurence D. Mueller, Univ. of California, Irvine, recently published by Elsevier.
  • This research study from JNCASR is the only one from a non-western country that finds a place in this collection.
  • It was the first experimental verification of the theoretical prediction that population stability may evolve as a by-product of natural selection favouring some life-history trait which traded off with other traits that directly affected population dynamic behaviour
  • For example, suppose a population inhabited an ecology wherein it was very advantageous to develop rapidly to reproductive maturity, even if it reduced subsequent offspring production.
  • In such a case, this population might evolve reduced offspring production, as a by-product for selection of rapid development to maturity.
  • The reduced offspring production, in turn, would result in relatively stable population dynamics.
  • A simplistic prediction from the theory of natural selection suggested that all else being equal, higher offspring production should be favoured by evolution.
  • Populations in which individuals produced large numbers of offspring would typically exhibit unstable dynamics.
  • This meant that their numbers would fluctuate a lot through time.
  • Therefore, if natural selection favoured higher offspring production, most populations would be expected to have evolved unstable, fluctuating dynamics.
  • These populations had evolved smaller body size and female fecundity as a result of evolving a greatly reduced larval phase.
  • The group then used these populations in an experiment where their population sizes were monitored in every generation in a nutritional environment known to induce unstable dynamics.
  • They showed that the faster-developing populations had indeed evolved greater population stability than their ancestral control populations.