Waiting4oblivion Parliament, lets try again, shall we? Options

[Burnt Sierra]

Right, a few rules before we start this time. No flaming. No intolerance of anybody else's viewpoint. No deciding you don't like the topic, and trying to tell people what they can discuss. This goes for everybody from now on.

Right, now we got the unpleasant bit out of the way, lets begin anew shall we?

p.s. yes Channler, those were the original rules, but seeing as how everyone seemed to forget them last time, I thought I'd make a little pointed reminder.

[Megil Tel-Zeke]

and i disagree with your concept.

Yes there is a natural carrying capacity that an ecosystem can handle. and this capacity varies depending on the species. and all species of animals, including humans fit into this. the thing is that no species knows its own carrying capacity they simply keep doing what they are hardwired to do, and that is survive and reproduce.

Now this is what happens, it is all a system of cause and effect, checks and balances per say. Since the system is too complex to look at it in its entirity we will break it down to just a few variables, Primarily because its easier to understand, and secondly because I don't want to be typing for all eternity.

So let's now get technical shall we ^ ^.



Alright, so theres a graph. populations grow exponentially as long as there are enough resources available to support the population, aso assuming resources are infinite, growth will grow exponentially infinitely. this is shown by the blue line in the graph.

We do know that resources are not infinite, so there has to be a limit on resources meaning there has to be a limit in population size. now the black line shows the carrying capacity in a natural environment. the red line shows the exponential growth of a population, but if you not as it nears the carrying capacity growth begins to slow down until it stables out. now this is a very generic model. But it helps us see two things.

1) some organisms such as Bacteria(and you can even say when u see a later char the humans grow this way too) reproduce so rapidly that their growth overshoots the carrying capacity by great quantities. What then happens is that resources are rapidles depleted and the populations dies of until a bit lower than the carrying capacity. it then stabilizes there.
2) other organisms follow the logistic growth, and are usually large and slow reproducing animals (elephants, Whales, etc)

Alright so the part where population is "stable" is very generic and it really looks more like this


In this example we have hares(prey) and lynxs(predator). as prey population increases, you see an increase in predator population. this makes sense since there is more food available and can support a larger population of lynxs. Now as the predator population begins climbing, the prey population begins dropping for ovbious reasons(i.e. predation, and also a depletion of their food source, grasses and other plants), what happens next is that the lynx population begins to decline because the amount of prey has decreased and the amount available is not enough to maintain the current population, so we see fewer cubs living to adulthood, and some adults dying from starvation. Also another factor here is disease. Disease spreads faster when organisms are grouped closely together. the larger the population the greater the chance of interaction between individuals and more chance for the transmittence of an antigen.

This system of checks and balances stops populations from going way out of control, and does so by keeping raising and lowering the Birth and death rates.

So with the exception of microbes, most populations will never ever excede their carrying capacity. There are however times when nature changes the carrying capacity, say by a natural disaster and the populations numbers plummet, if not enough resources remain a population can entirely die out, and sometimes evena species. so species do do extinct naturally, it is not a solely manmade problem.

So no we leave the realm of wildlife and go into humans. This is a chart of the human population since 4000 BC.


as you see we have had a pretty constant population growing relatively slowly. it is however during the last 1000 years that the human population has undergone a population explosion. now if you tell me this is a solely natural accident then you are just thick headed. over the past 1000 years mankind has gone through the industrial revolution, the creation of machines, also great innovation in the world of hygiene and medicine. We have as mankind knowingly reduced, and sometimes even reduced the checks that keep our population under control. we have eliminated virulent disease, created machines to do work for us, letting us produce more than ever before. and with the development of genetics and biotechnology we have altered our diets, and in some cases overcome the genetic problems that plague our species.

No you saw the population cycle with teh hares and lynx. alright well here is a graph of birth and death rates of sweden and mexico.



Lets just focus on one of the two nations, Sweden. Tis phenomenon has occured only with humans, and is called the demographic transition model.

normally populations have high birth rates and high death rates. reason being that a family would have lots of children to ensure some survived to adult hood. alright, well thanks to technology and civilization we have managed to decrease the death rate, since we can extend lif with medicines, and also ensure that more children will live to adulthood. This causes family size to decrease since we no longer need to worry about most of the children dieing of. As long as birth rates exceeds death rate, populations will grow. We are now seeing a phenomene which is labeled the 5th step of teh transition model. This is happening in a few european nations where death rates exceed birth rates and we have a population decline. but I digress.

All of this is just to show that we as humans have succesfully increased the carrying capacity. the question is not whether we can keep it going forever becuase thats just not possible. the question is when will we push nature to the max and reach that final carrying capacity. When we reach this capacity, it is not to say we will all die out, but we will instead have a pretty constant population.

So doomedone, you cannot argue that mankind has not modified nature and in doing so, allowed our population to grow so large.

and with this I rest my case.

This post has been edited by Megil Tel-Zeke: Aug 12 2005, 05:26 AM