davidstuart

u/davidstuart




r/askscience•

Taking a late-winter hike in the forest today, I could see a lot more of the forest than usual due to the lack of leaves. I noticed many trees that had ivy growing up the trunk. Except for poision ivy (which grows straight up the trunk), all the other types of ivy plants spiral up the trunk in the same direction. From a birds-eye view, the ivy curved around the trunk in a clockwise fashion as it climbed. That was true without exception in more than 50 trees I saw with ivy. an example Why a left-handed spiral, and would it change in the southern hemisphere??

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