LET ME CLEAR WHAT I ADVOCATE IS NOT A THEORY ,NOR A HYPOTHESIS.

it is a universal law of nature

If u get a chance to read demography ie. study of human population .
let me give an example .

:"lemmings (rat like species ) in tundra ,follow a j-shaped growth curve .
it simply means ,that ,
they eat all the food avilable to them ,flourish in numbers .
they eat ,they eat ,they eat ,
they reproduce ,
they reproduce ,
they reproduce ,

POPULATION EXPLOSION OCCURS (AS IN INDIA)
FOOD ,MEANS OF SUSTENANCE ,SHELTER BECOME SCARCE (AS IN INDIA)

POPULATIONS FIGHT ,IRRITABLE ,UNREST .
NEXT STAGE

the lemmings are naturally programmed creatures with a suicide gene incorporated ,one day ,whole adult population of lemmings ,out of saturation ,marches in millions in numbers ,dies by jumping off a cliff into sea.
thats a part of darwin's theory of natural selection.
death is a very nice tool ,reason could be war ,famine ,hunger ,suicide ..
its nice cos its necessary for survival of new generation .