Chapter 3: Figure and Ground
48 - Loose Behavior
The use of counteracting forces is one of nature’s favorite tricks. The tension between individuals and their environments isn’t unique to Manaus and the Amazon basin; it’s as old as life itself. In embryo development it means, on the one hand, aggressive growth and a dynamic game plan for the nucleus and, on the other hand, the shaping force of factors imposed by the cytoplasm. How is that tension resolved? The answer lies in a sweet spot.
In developmental terms, being “robust” means being able to resist change. For a growing embryo, it’s the ability to withstand disturbances and emerge from the prenatal process as normal and healthy. Another phrase to describe robustness would be “dynamic stability.” And in this concept lies what could be the most remarkable thing about , development.
A growing embryo is a roiling mass of transformations—in just forty-eight hours a fertilized frog egg becomes a free-roaming tadpole; human fetal brain neurons grow at a rate of 250,000 per minute. Through all that the embryo is, as Kant pointed out over a century ago, “both an organized and self-organizing being” whose growing parts at the same time also have to produce one another. Add to that ongoing convulsion the effects of skewed signals from genetic mutations at its core, and of environmental pressures buffeting it from without, and there’s a certain wonder in the fact that anything recognizable emerges, much less a complex and fully functioning life form.
The developing embryo is by definition always changing, moving forward through biological time on a kind of trajectory. So maintaining stability by the use of static means is not an option: dynamic sequences cascade through fields of interacting networks; nested systems of multiple, transient causes and effects advance as they coevolve. Robustness is the result of nature’s ability to channel the developing embryo—in the lingo, to “canalize” it. The biologists’ metaphor is that of a landscape. Developmental valleys provide equilibrium pathways, hills offer gently rising resistance.
And therein lies a lesson. The concepts of adaptation and evolution are the linchpins of modern biology. At heart they are expressions of the tension between figure and ground, between the individual and its environment. Mutation in an individual, without environmental constraints, would just produce genetic chaos. On the other hand, if constraints from the environment were too tight, the individual would lose all identity. Nature’s solution to this dilemma is a sweetly funky one: it favors a “loose coupling.”
Philosopher of biology Susan Oyama
Play is the key. The lesson is that along that boundary where the push of individual initiative comes up against the shove of environmental constraint, nature finds a sweet spot—a vibrant zone where the tensions between figure and ground are resolved in dynamic interaction.
This interplay happens between the nucleus and the cytoplasm in development; it then occurs again in the outside world, along the boundary between the fully grown individual and its environment. Through this constant interplay, animals evolve tools to negotiate that boundary: tools such as senses and mobility.
