The middle heights of the Himalayas are particularly pleasant. The famous British occupation-era “hill stations” of Shimla, Darjeeling, Naini Tal, Dalhousie, Mussoorie, among others lie at an altitude of about 2 Kilometers above sea level. These famous destinations are now monstrous scabs on the flanks of the Himalayas, where tourists still flock. But away from these madding crowds are nameless villages dotted across the mountains at similar heights. They lie nestled in little flat pieces of land accidentally created by opposing slopes coming together. These accidental valleys often have water, and look out on pleasant meadows full of wildflowers. You see one of these in the featured photo. It is the Himalayan baby’s breath (Gypsophilia cerastioides)
These bushes spread out from below rocks, as you can see in the photo above. In late spring the low bushes are full of the five-petaled white flowers. The Young Niece asked the obvious question, “Why are there five petals?”. Once I’d asked this to a practicing research biologist and got the uninformative answer, “In biology we ask what, not why.” If you ask the Oracle of Google “Why do flowers have five petals?” you remain baffled. The most useful answer turns out to be “Because they are descended from other five-petaled flowers.” I know that another niece would have said something like the number of petals is a number in the Fibonacci sequence, and is related to the Golden Ratio. That is as unhelpful as the answer by the biologist. When we ask why, we would like to have an answer which gives us a chain of causes and effect. Anything else is just resetting the question in a different context.
Further downslope, where the meadows grow less rocky one can find fields of balsam. I don’t think I’ve seen this species before, with its long serrated leaves and the cup-shaped purple-pink flowers with large white anthers full of pollen. I was unable to identify it better. Interestingly, balsam also has five petals. The best argument from causes that I have read about pentapetalism (to coin a new word) was developed by Yutaka Nishiyama at the Osaka University of Economics a few years ago. He argues from the observation that the tip of the growing bud has to be convex. A five-fold symmetry at the growing tip is the most stable way to achieve this, for the same reason that a soccer ball has some pentagonal panels. Since petals grow out the tip of the growing bud, they will have five petals. His argument does not rule out other numbers of petals, but explains why almost 50% of families of flowering plants have five petals.
I include the flowers which you can see in the photo above not because they are wild, but because they are green. I saw them in one of the fields terraced out of a slope for agriculture. If there is something I know less about than wildflowers, it is farming. I am totally unable to say what these plants are. I’m sure if I’d stopped a local and asked I would have had instant enlightenment. Around the edges of these fields we saw the bright red flowers of large-mouthed poppy (Papaver macrostomum). That’s another five-petaled flower!