Humans just a stress?

[Fishteacher73]

There are a number of animals that can breed across species lines. But they are distinct species. The red wolf (Canis rufus) and the domesticated dog (Canis lupus familiaris) are individual species.

 

In taxonomy the distinction among species/sub-species/variants is debated.

 

The current defintion of a species: A group of organisms formally recognized as distinct from other groups; the taxon rank in the hierarchy of biological classification below genus; the basic unit of biological classification, defined by the reproductive isolation of the group from all other groups of organisms.

 

By reproductive isolation, it is referring to breeding populations, not the biologic ability to hybridize.

[pgrmdave]

Fishteacher - what about trilobites? They are extinct, and did not evolve, they died out because other organisms were better at adapting.

[Fishteacher73]

We still have lineages from the trilobites (Isopods).

 

Trilobites were originally thought to have become extinct due to advances in predation and issues with shedding a chitinous exoskeleton. The problem with this idea is that most of the modern arthropods still molt in the same manner, yet did not die off. While the molting issue played a factor, the current theory involves the shift of ocean chemistry as the culprit.

[Fishteacher73]

While I feel that in our natural history there really have not been extinctions tied directly to the actions of another species (or at least any evidence), I will concede that in the multitudes of various interactions, one species possibly may have caused an extinction. This seems to be a possibilty, but not ever any real force in shaping the fauna.

 

Humans have been linked to 734 animals (697 species and 37 subspecies) as recently extinct (extinctions since 1500 AD) according to a 2004 IUCN (The World Conservation Union) report. This just animal species, much less what we have done to the flora of the world. More have already been added this year (32 Days).

 

Here's a link to the whole report:

 

http://www.iucnredlist.org/info/tables/table1.html

[pgrmdave]

You still haven't provided any reason that extinction is inherently bad, merely that humans cause it - not a fact that I doubt, nor do I disagree with. I disagree with the idea that it is inherently wrong, unless you mean that it is detrimental to humans in the long run, in which case, I may agree.

[Fishteacher73]

I disagree with the idea that it is inherently wrong, unless you mean that it is detrimental to humans in the long run, in which case, I may agree.

 

That is my point. Extinctions allow for new radiation of life-forms. The problem is that the accelerated rate at which humans are causing extinctions is detremental to humans. Life will survive. We are hacking away at the under pinnings of our ecosystem. And it is going to be humans that disappear, we make take a few lemurs with us, but there will be options for the remaining life to fill in.

[pgrmdave]

I was arguing against something you said before:

There should not be an argument. The evidence is massive for the fact that humans are a detriment to the Earth at our current path. This is paramount to arguing that gravity is a myth

 

To say that we are a detriment to the earth, in my opinion, is wrong - to say we may be hurting ourselves is correct.

[Fishteacher73]

To say that we are a detriment to the earth, in my opinion, is wrong - to say we may be hurting ourselves is correct.

 

We may be just arguing semantics, but for something not to be a detriment, it must either have a neutral imapct or a positive impact. I see no evidence for a positive impact, and there is plaenty of evidence that there is a negative impact, and therefore no longer neutral.

 

I cannot see where a "may" come into that statement. Through science we have gained knowledge to stem off a lot of the natural causes of death, but in the process gained a whole new cadre of problems. I don't think that cancer was that big of an issue 100 years ago. Today it is one of the leading causes of human mortality. Most cancers are caused by external carcinogens produced by man. Humans are vastly overpopulated in many areas and really would not have a sustainable existence if not for external assistance.

 

Human as a whole (in the past 40,000 years or so) have genneral not been that big of a deal, but in the past 100 years we have accelerated so many hazardous ecological phenomenon that the present course seems to be into the ground. Without large scale shifts in the daily existence of humans we are running out of time.

[pgrmdave]

I don't think that cancer was that big of an issue 100 years ago. Today it is one of the leading causes of human mortality.

 

I have no evidence, but rational thinking - 100 years ago, people were dying of so many other things that no one thing, i.e. cancer, was as prominent. If people are dying before they can develop cancer, then of course cancer will not be a big problem.

 

Most cancers are caused by external carcinogens produced by man.

Most cancers are self-inflicted, by tobacco, alcohol, and food: http://www.drug-rehabs.com/alcohol-tobacco-cancer.htm

[Fishteacher73]

Most cancers are self-inflicted, by tobacco, alcohol, and food:

 

Processed man-made items. While these substances may naturally occur, man is refining them for its own consumption. We are burning the candle at both ends so to speak. Being natural is not always a healthy thing. The neurotoxins produced by some venomous snakes are natural, I still would not want to ingest the substances.

 

I seem to be constantly on the defensive on this issue. Do you have evidence that humans are not a detriment? (I'm not trying to be argumentative, but I would like to see some backing for your position. I feel I am making my case.)

[pgrmdave]

I simply question your definition of detriment. I have found that many people think that extinction of species, death, and massive change of ecosystems is detrimental, while I don't think so. I think that it is merely another evolutionary pressure. I've also heard a lot of people talk about 'fragile' ecosystems, which really are only fragile if you assume they should never change. I think that the only thing that is truly detrimental is that which would harm human existance, not that which would harm other life. I think that central to this debate would be a mutually agreed upon definition of detrimental.

[Fishteacher73]

Well being human I guess I am a bit biased to the human condition. I would be comfortable just discussing the concept that human's actions are detrimantal to themselves. Ecosystems are not fragile, but they can warp easily. Being on the top of the food chain means that subtle shifts become magnified to us. We will not destry life, but we definatlely are on course to destroy ourselves. The exponential growth of ecological threats to humans I think is out pacing out scientific efforts to solve them.