Thap, thank you very much for taking the time to write out your detailed responses. (By the way, I hope you’re not still stuck in Egypt and were able to make it back to Pakistan). Mursalin is so accurate, this is interesting stuff. You seem knowledgeable about this and willing to take the time to reply, so I hope you will bear with the stupid queries that are about to follow
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Extinction and evolution of species is constantly occurring…the biosphere is not static. There have been many periods in the geological past (not extinction events) when the rate of species disappearing was much higher.
I agree with that. However, as you mention those extinction events were caused by natural factor - the Krakatau (sorry for the misspelling) volcanic explosion is one example; yes it definitely caused severe stress upon ecosystems and biomes but it may be considered as a natural part of the Earth’s geological history. Following the explosion, at least our planet’s ecosystems had sufficient time to rejuvenate and adapt to the stresses caused by the explosion. I think on the contrary, anthropogenic events exact a much more demanding toll upon the earth, globally as well as locally, because we allow absolutely no time for the earth to heal itself.
For example, the numbers of plant and animal species becoming extinct in Costa Rican rainforests, as a result of human interference, is approx. 50,000 every year, an average of about 140/day. http://www.pbs.org/tal/costa_rica/facts.html
According to the same source, 2000 trees are cut down in the rainforests every minute. Two thousand may not seem like a whole lot if we think on a global scale, but in my opinion at least it’s significant for the following reasons - replanting of trees in tropical countries occurs at the ratio of 1 replant for every 10 trees cut down. (In some countries, the ratio is 1:30). It’s true that other historical natural events have had massive effects upon earth’s ecosystems, but at least with regards to those events, the earth was subsequently given time to recuperate. Gradually reforestation occurred, with even perhaps enhanced biodiversity amongst both plants and animals; today, human interference prevents this planet from going through the natural mechanisms it possesses to heal itself. So, in my humble (and possibly very wrong) opinion, the per-minute loss of 2000 trees represents an ecological devastation on many fronts - rate of replanting is minimal compared to the rate of deforestation. Cutting down 2000 trees in the rainforest per minute would not be as catastrophic a global event, perhaps, if we were simultaneously replanting at least 1000 trees per minute - but we are not. What also doesn’t help, perhaps, is that global demand for paper and other byproducts of wood is not decreasing.
We only inhabit, as a civilisation less then 20% of the planet…we do not have much affect on it as a whole… The Earth is in flux, it’s atmosphere, it’s crust and the chemical nature of the oceans. We aint that special globally…we are natural…anything we do is natural… most man-made/anthropogenic causes for global catastrophes have to be seen in context of the geological record.
I wholly agree with your statement that we are not that special globally, but I’m not so certain that “anything [humans] do is natural”. (This is where my especially stupid part comes in) - in my environmental science class, we were taught that every organism and species possesses an ecological footprint (EF) - isn’t it true that, geologically speaking, natural-caused events leave a much small EF than anthropogenic ones? Particularly since the Industrial Revolution in Europe during the 1800s, we have been responsible for much of the plant/animal species loss, smog and associated respiration problems, species interbreeding due to stock depletion and the associated genetic problems, water pollution, etc., than any other factor(s)?
True, climate fluctuations have ALWAYS been occurring - nothing new about that. But the rate at which we, through our habits of mass consuming renewable and non-renewable resources, drastically alter the earth’s climatic patterns without allowing any appreciable time whatsoever to the ecosystems, biomes, and the organisms that inhabit them to adjust and recover - is different and unique, and that makes our ecological footprint on this earth much more larger, and dangerous, than any one else’s.
(Sorry if I said anything stupid in the above, to be honest I’m still trying to figure my way through this whole issue of the environment and apologies if I blabbed anything wrong).