Hi Jim, Today I spoke to Chelsea Specht, professor of plant morphology and monocot evolution at UC Berkeley. She said that we don't really know why the leaves are carried upside down, but she offered a possible answer. Alstroemeria and Bomarea are relatives, they share a common ancestor. Bomarea stems climb on other plants and if you look closely they actually twist their leaves so that the leaves face the sun (I went out to look at my plant just now and it did exactly that!). As a result, some of the leaves will be resupinate (twisted), others will be non-resupinate (regular). This may be the case with Alstroemeria too, but they don't climb and the chances of them falling over isn't too great. But if that did happen, maybe they too can untwist their leaves (experiment with your plants and see). So perhaps somewhere in the common ancestor of Bomarea and Alstroemeria, the leaves acquire this twisting mechanism and Bomarea kept it, some Alstroemeria kept it, and others lost it as Jane pointed out. It makes sense. If you don't use it, you loose it. Nhu On Wed, Jan 16, 2013 at 2:34 PM, Jim McKenney <jamesamckenney@verizon.net>wrote: > I'll ask again a question which I've asked in the past without eliciting > a serious response. Does anyone know why the leaves of Alstroemeria are > carried upside down? >