Thursday, September 19, 2013

Love in a Puff

Plant names are often whimsical, their origins obscure. Kiss me over the Garden Gate. Forget me not. Hollyhock. Who came up with these names, and why?

Love in a Puff is a more literal description, or so it seems at first. A wonder of geometry, each bilaterally symmetrical (or nearly so) leaf sports a triplet of three-part leaflets. Each flowering stem produces a pair of tendrils, from which spring three branchlets, each with three tiny buds. The buds burst into petite white blooms, each one becoming a puffy three-sided balloon. Hence the “Puff” in Love in a Puff. The trinities do not end there, for inside of each Puff are three partitions, and clinging to the three-wall joints are three round, black seeds. Inscribed on each seed is a perfect ivory “heart” (known in math circles as a cardioid, albeit slightly modified), hence the Love.

Cardiospermum halicacabum seeds
Love, or at least the cardioid shape, is everywhere in my garden. Redbud leaves and wood sorrel, moonflower and salvia, katsura, violets, hosta all have heart-shaped leaves. Almost always, they unfold gracefully from a center seam, each side the mirror image of the other. Sometimes, they fold up at night. But the hearts that hide in puffs have no center seam, and they expand, rather than unfold. Are they scars, enlarging from the center point of attachment? How they came to be so reliably heart-shaped rather than sensibly circular is a mystery. 

'Forest Pansy" redbud leaf. Note the folded young leaves.
We, like almost all animals and most leaves, are bilaterally symmetrical, at least on the outside. Scientists attribute symmetry in animals to the fact that, if we are to propel ourselves in an efficient fashion, the mirror image model makes the most practical sense. Right foot, left foot, we walk, arms swinging in opposing directions. On the inside, asymmetrical design has taken over some core functions. Intestinal tubes fold and roll, pushing other organs off pattern. The heart itself is neither “heart”-shaped nor is it symmetrical. It’s more like a screw. 
Which begs the question: how did we come to associate the modified cardioid—comma facing comma—with love in the first place? It took a few centuries, as it turns out. The long story involves ivy leaves, playing cards, and religious icons. Eventually Hallmark came along and sealed the deal.  (see below for a more complete explanation)

Outside of the animal kingdom exist types of symmetry other than the bilateral that shapes our preferences and our design sensibilities. The rotational symmetry of flowers (and the three-sided Puff), the spirals of nautilus shells and sunflower heads, and the six-sided symmetry of crystals follow rules of their own. Rooted organisms have no need for economical locomotion. Floaters have other options. The mathematics of the multiple spirals of pinecones that run both clockwise and counterclockwise have been figured out, named, and categorized, but that does little to diminish the mysteries. 

We have always taken our cues from nature. Sacred trinities and technologies draw from its wealth. The hexagonal combs of the honeybee inform aeronautic materials. The famous Guggenheim Museum borrows from the nautilus. The bilateral symmetry of skeletal frames infuses the arts, the automobile, the Taj Mahal, the Brooklyn Bridge. 

Seeds still attached, at the heart, to the inner walls of the puff

The perfect Puff—light as air yet strong, geometrically intriguing, poetically beautiful—is as elegant a structure as exists anywhere. Its three-walled pod, the climax of a series of threes, inflates, seemingly magically, when our heads are turned. So it is fitting that it’s name bursts with enigmatic romance. A source of inspiration, to be sure.