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Published by MrILoveTheAnts
09-25-2012 |
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#2
By
MrILoveTheAnts
on
09-26-2012, 12:58 PM
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![]() Quote:
When the plant is being imported just for its looks though, that should be banned. Exotic pets fall under this catagory too, how many venomous snakes, and tropical fish does one need? Why are we importing lady bugs when we have over 400 native species? Why is the Chinese Praying Mantis used and not the 20 native Mantises we have in North America. Honeybees make sense because they're a food crop in their own right, an essential for monocultural farming. Going back to ornamental plants though, a lot of them are tame and perfectly safe in the landscape. However a few of the insect pollinated species we've imported are only tame because their ideal pollinator hasn't yet jumped the ship. Now adding another pollinator species to the 4,500 North America already has doesn't sound all that bad but because nothing is controlling the spread of this plant and it has a pollinator who 9 out of 10 flower visits will produce a viable seed it's easy to see how a new weed is born. We're just adding and adding species onto less and less land. Back when the continents were all connected this didn't matter all that much. But as they've separated the species have all gone their separate ways, with their pollinators, with their lepidoptera, and on up the food chain. Where the land is still connected, or had only recently vanished is where we see species that are related to one another closest. Raspberries and I think Strawberries for example are found in both Canada and the norther US, as well as Russia, Asia, and the northern parts of Europe. So has happened in the past but doesn't really happen on its own anymore. Islands are a different issue. The Oceans, Lakes and Rivers too. Now where this all falls apart is a billion years in the future or whenever all the continents eventually bump back into one another. When that happens, species jumping from one land mass to the other will be unavoidable. It would certainly be an event worthy of marking a different era. But thinking this simply negates all conservation efforts is like skipping ahead to the end of a book and not enjoying the bit in the middle. |
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#4
By
turttle
on
10-22-2012, 07:47 PM
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![]() One thing I think is really cool is the concept of "aeroplankton". Lichens are truly global in their speciation, bounded by latitude rather than continental boundaries, because their spread is controlled by the wind. They simply release spores into the wind and they can be carried anywhere that wind goes. Where the fungus part of the lichen ends up, it then has to wait for the right algae from the aeroplankton to also land.
In a sense, air travel has made us all "aeroplankton", blowing in to places you wouldn't think we could go. The problem with invasive plant species and all the ornamentals, is that the cat is too far out of the bag to ever get really put back in. And our North American plants are causing just as much trouble elsewhere as the Eurasian and African plants are doing here. I would love to read a book on the subject by you! |
#5
By
MrILoveTheAnts
on
10-22-2012, 09:11 PM
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![]() How our native plants behave in other countries is something I'd love to read about, let alone write. The only one I've really herd about is as being invasive is actually our beloved Black Cherry Tree, Prunus serotina, in Europe. Apparently the only reason it's so tame in North America is because of a fungal pathogen in the soil that restricts germination. Though that's just going on my memory.
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#6
By
Rebek56
on
10-27-2012, 06:36 AM
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![]() Our eastern gray squirrel is causing serious problems for the British red squirrel. http://www.nytimes.com/2007/10/07/ma...anted=all&_r=0
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Tags |
ecology, pangaea |
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