This could be in science but is better suited here and will be more fun.
Some simple maths based on reproduction rates indicate that the worlds population could easily reach current levels within 4,500 years from an origin of 2 human beings.
Science tells us that human beings have been round for what, a hundred thousand years, maybe more. Using the same reproductive rates there would by now be more humans on the earth than there is physical space for. So we must have been reproducing so slowly that we would have almost died out before we got going.
So when did we start having more sex?
Originally posted by divegeesteranswer = Medical Science.
This could be in science but is better suited here and will be more fun.
Some simple maths based on reproduction rates indicate that the worlds population could easily reach current levels within 4,500 years from an origin of 2 human beings.
Science tells us that human beings have been round for what, a hundred thousand years, maybe more. Using the ...[text shortened]... at we would have almost died out before we got going.
So when did we start having more sex?
Look at Infant mortality rates
Look at the Life expectancy increases (for 1st & 2nd world countries)
Got (almost) nothing to do with how often we "do it"
Originally posted by divegeesterSince the Industrial Revolution ... but that has nothing to do with population growth.
This could be in science but is better suited here and will be more fun.
Some simple maths based on reproduction rates indicate that the worlds population could easily reach current levels within 4,500 years from an origin of 2 human beings.
Science tells us that human beings have been round for what, a hundred thousand years, maybe more. Using the ...[text shortened]... at we would have almost died out before we got going.
So when did we start having more sex?
Originally posted by divegeestermaths doesn't account for disease, predators, wars famine.
This could be in science but is better suited here and will be more fun.
Some simple maths based on reproduction rates indicate that the worlds population could easily reach current levels within 4,500 years from an origin of 2 human beings.
Science tells us that human beings have been round for what, a hundred thousand years, maybe more. Using the ...[text shortened]... at we would have almost died out before we got going.
So when did we start having more sex?
"Some simple maths based on reproduction rates indicate that the worlds population could easily reach current levels within 4,500 years from an origin of 2 human beings."
no. i could go into how cheetahs are endangered from being to few (at a population of thousands). how disease, famine, predators would eventually off a population of 2+children, how birthing in unsanitary conditions with a non-doctor like adam would be the death of you.
but i won't (i just did).
Originally posted by nook7Yes I can see how advances in medical science who positively impact infant mortality. However, the significant advances that do impact infant mortality have only been available to the masses for what... a couple of hundred years if that, and then only in 'developed' countries.
answer = Medical Science
Human population has been growing exponentially since way before then, how would you explain that?
Originally posted by divegeesterData, please. Other than the fact than the populations of organisms in petri dishes grow exponentially. until the limits are reached.
Yes I can see how advances in medical science who positively impact infant mortality. However, the significant advances that do impact infant mortality have only been available to the masses for what... a couple of hundred years if that, and then only in 'developed' countries.
Human population has been growing exponentially since way before then, how would you explain that?
Originally posted by divegeesterIt is not just medical advances. It is also technological advances such as farming / animal husbandry and the various technologies required to allow cities. Even the wheel and draft animals are quite important for moving goods into cities.
Yes I can see how advances in medical science who positively impact infant mortality. However, the significant advances that do impact infant mortality have only been available to the masses for what... a couple of hundred years if that, and then only in 'developed' countries.
Human population has been growing exponentially since way before then, how would you explain that?
Prior to the development of various sanitation technologies (even if it is as simple as carting off the excrement in buckets) most cities would grow to a certain size then suffer major epidemics.
I also suspect that you do not actually have human population statistics for most of the world and are actually incorrect about exponential growth. Certainly here in Africa, I do not believe the population grew significantly until European colonization brought greater peace and western medicine/sanitation.
I've been looking at a few sources for examples.
http://edblock4.wikispaces.com/
http://www.susps.org/overview/numbers.html
There seems to have been a "kick" around 1000 years ago but the real exponential growth from mid last centrury.
Not convinced that medicine has the significant impact; farming and other industrial factors possibly.
But humans in their current state of intellect have been around for hundreds of thousands of years and in their current behavioural state for at least 50,000 years - so what have we been doing all this time?
http://en.wikipedia.org/wiki/Human
Originally posted by divegeesterSome of the biggest killers in the last few centuries were plagues and wars (with the plagues winning I believe).
Not convinced that medicine has the significant impact; farming and other industrial factors possibly.
I think you discount medicine without realizing how old medicine is and how much an impact small discoveries can make.
Its interesting that the graph in your first link does not show major dips at the world wars or for the various plagues before that. The Black death for example killed 30-60% of Europe's population. The Spanish flu killed 3-6% of the worlds population.
Here in Africa diseases like Malaria have kept population growth down. My sister tells me that treated mosquito nets has made a big difference to infant mortality where she lives (in semi-rural Zambia).
When European settlers first came to Livingstone, they settled by the river and most died of malaria. For this reason, the town was moved away from the river (which presumably reduced the incidences of malaria). Such a simple thing as choosing town locations carefully may not seem like much and may not seem like 'medicine', but over time such planning based on observation can significantly improve life expectancy.
Originally posted by divegeesterEducation systems (including the advents writing and printing) and increased life spans have made us much more capable creatures. Without an education system that starts teaching children at an early age, and with low life expectancy, there really isn't the time to learn and discover very much. Then you need some way to pass on those discoveries to those that come after you.
But humans in their current state of intellect have been around for hundreds of thousands of years and in their current behavioural state for at least 50,000 years - so what have we been doing all this time?