#11
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Re: Species impact
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It will certainly be a domesticated species. Probably cattle. [/ QUOTE ] Globally, why cattle? |
#12
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Re: Species impact
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A clear choice didn't pop up for the people having the conversation that inspired this thread. One of the things I was thinking of is not what affects the ecosystem but what prevented humans from affecting the ecosystem. For example, malaria was, and is, really an impediment to developing the kinds of nature obliterating civilization seen outside of the tropics. So one of the Plasmodiums could be a reasonable choice. But then, maybe we just need to consider one of the Anopheles mosquitoes as the species here, since they are the vector. I still feel like I'm missing something obvious. [/ QUOTE ] When I first opened the thread i was thinking rats as far as other mammels go. I don't really know how many different species of rodent are comomnly associated with humans, but some have been responsible for extinction of quite a few species when they were transported to islands, and have carried quite a few major deseases with them. |
#13
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Re: Species impact
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[ QUOTE ] It will certainly be a domesticated species. Probably cattle. [/ QUOTE ] Globally, why cattle? [/ QUOTE ] Cattle have a huge impact on the local ecosystems where they graze. But globally, domesticated animals like cattle and pigs contribute more greenhouse gases than do automobiles. It was in the New York Times, so it must be true. |
#14
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Re: Species impact
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One of the things I was thinking of is not what affects the ecosystem but what prevented humans from affecting the ecosystem. [/ QUOTE ] Rduke, I think there are 3 questions here all of which are interesting: 1) The original question as to which species is currently second after humans. 2) The one given in your quote above as to what species prevents humans from having an even greater impact on the ecosystem. 3) And which species if humans were all removed from the planet tomorrow, would have the greatest impact on the ecosystem to the detriment of the most other species. I don't know the answers, but tolbiny's rat answer is likely a good candidate for #2 as is yours regarding the mosquito. However as 3/4 of the planet is covered in oceans, something aquatic like algae also has to be considered. And the fact that there is currently no other primate species capable of making fire is also significant regarding atmospheric impacts. But regarding #2 again, there might not be a dominant disease causing virus or bacteria that holds humans back from a greater impact, but rather a group that collectively does so, or which alternate over time. It is also worth noting, that many predator species that would otherwise be candidates for the original question, are held in check if not extincted by humans, so the real second place might not be the same if humans didn't have as great an impact on those other predators. |
#15
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Re: Species impact
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I don't know the answers, but tolbiny's rat answer is likely a good candidate for #2 as is yours regarding the mosquito [/ QUOTE ] I think the word species here is what makes it so difficult to answer for a non specialist (ie me). I think Borodog is on the right track by looking at atmosphereic changes as they can effect the entire world more easily than other changes, but i think hes got it backwards. I would look at carbon fixing organisms first, things like coccolithophores which are responsible for the White Cliffs of Dover and other enourmous deposits of calcium carbonate. I also think that they effect the pH levels of the ocean (trying to remember 10th grade biology here), which would be an enourmous impact. Problem is there could be thousands (or more) different species contributing to this process, how to estimate the impact of one? |
#16
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Re: Species impact
I'll hazard a guess.
Worms. What other species currently reorganizes the most biomass to positive benefit? |
#17
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Re: Species impact
Great questions.
[ QUOTE ] But regarding #2 again, there might not be a dominant disease causing virus or bacteria that holds humans back from a greater impact, but rather a group that collectively does so, or which alternate over time. [/ QUOTE ] This is why I picked malaria/mosquito. It definitely is an obstacle to human civilization and, more importantly for this debate, is located in a certain place (say, the tropics) of really high biodiversity and can "protect" that area. While other diseases may kill more humans at certain times (influenza, plague, etc.) they don't have the effect or localization malaria has. That's also why I don't think rats are as good of a choice as the mosquito vector, they're pretty much everywhere and while they can have on effect on controlling human density, I don't think they have nearly as much effect. I did see something in Discover and other places on them wiping out species that I thought was interesting. [ QUOTE ] However as 3/4 of the planet is covered in oceans, something aquatic like algae also has to be considered. [/ QUOTE ] Yeah, here's where the species question comes in. As groups of species, a lot of other organisms have a greater effect than humans (like algae). Maybe we could go to the genus level (still be in the letter of the OP since we are the only extant species in our genus) [ QUOTE ] It is also worth noting, that many predator species that would otherwise be candidates for the original question, are held in check if not extincted by humans, [/ QUOTE ] But predators are often affecting small local populations (as opposed to tropical diseases - which have a much larger area). I think that the rat would definitely drop down the list if humans went extinct. |
#18
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Re: Species impact
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I think the word species here is what makes it so difficult to answer for a non specialist (ie me). [/ QUOTE ] Yeah, I think this may be a problem. But I think we can still limit it to a couple species in a genus or something. [ QUOTE ] I think Borodog is on the right track by looking at atmosphereic changes as they can effect the entire world more easily than other changes, but i think hes got it backwards. I would look at carbon fixing organisms first, things like coccolithophores which are responsible for the White Cliffs of Dover and other enourmous deposits of calcium carbonate. I also think that they effect the pH levels of the ocean (trying to remember 10th grade biology here), which would be an enourmous impact. Problem is there could be thousands (or more) different species contributing to this process, how to estimate the impact of one? [/ QUOTE ] Yeah, also I'm vaguely remembering some papers on the rise of agriculture, rice, and preventing ice ages. Anyone remember those? |
#19
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Re: Species impact
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We'll say humans have impacted the global ecosystem the most. What species is second? [/ QUOTE ] Mitochondria. (It was a species once!) |
#20
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Re: Species impact
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[ QUOTE ] We'll say humans have impacted the global ecosystem the most. What species is second? [/ QUOTE ] Mitochondria. (It was a species once!) [/ QUOTE ] Cheater. |
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