Let’s imagine that the sum of what we humans know about the living world is a sphere—like a lustrous, red balloon. The surface area of the sphere is proportional to the amount of knowledge we have. I should point out that I am not the first person to make this analogy (was it Carl Sagan?)—I am just twisting it for my own sinister purposes. Anyways, the sphere started off very small, back in the day when we were chucking rocks at each other and spearing woolly rhinoceroses for supper. Whenever someone figured out some key truth about the biological realm and that truth was disseminated amongst the rest of humanity, the sphere expanded, as though the discoverer had blown a puff of air into the sphere/balloon. Every little discovery puffs up the balloon too, but to a lesser extent.
With the rise of the industrial revolution and communications technology, the balloon expanded hella fast—puff, puff, puff. I would say that after about 1600 C.E., when the Scientific Revolution began, the world’s first real biologists were causing the balloon to expand rapidly. Then along came Darwin. Darwin’s theory of evolution by natural selection damn near caused the balloon to pop. Since every bedbug, wombat, slime mold, marmoset, spirochete, and tunicate—every living organism—is the product of evolution, all of biological knowledge is unified by the theory of evolution. Darwin’s was the single most voluminous lungfull of breath that has expanded the balloon of biological knowledge. That’s what I say, anyway, and this is my imaginary balloon so I can say what I want.
The space outside the balloon represents the great and mysterious realm of what we do not know about biology. It’s dark and spooky out there in the void. So check this out: as the balloon gets bigger, as we understand more and more, the balloon’s surface area comes into contact with more and more of the unknown. So the more we know, the more we know that there is so much more that we don’t know. Get it? If you consider the formula for the surface area of a sphere, where surface area = 4πr^2, you can see that as the radius of the sphere doubles, the surface area actually increases by a factor of 4! The more we know, the more we know that we don’t know. This may not be how it really works, however. The realm of what is unknown may not be infinite, at least when we are talking about biology. Who really knows how much we don’t know?
Another part of this balloon model, if I can call it that, is that there may be a real limit to what humans can know about the living world. Even if there is a whole lot more to learn out there, the finite computational power of our little chimp brains and the limitations imposed on our technology by the laws of physics may prevent us from puffing up the balloon forever and ever. Perhaps the rate of the balloon’s expansion has begun to slow, because we are nearing the limit of our ability to make major scientific leaps and bounds. Can there ever be a new discovery as monumental as Darwin’s?
Something amazing has happened in the last few decades, however, that has certainly quickened the balloon’s expansion. With the rise of a relatively globalized scientific community and the gol-danged Internet, we are puffing right along. Now biologists from Japan can communicate in real time with biologists in Mexico via email, Skype, etc. We have instant online access to journal articles, genetic databases, museum records, satellite data, etc. There is SO much information and we can all share it with one another RIGHT NOW! Darwin had to send stupid ol’ paper letters to his colleagues and wait weeks or maybe months for responses. Crazy! Through the Internet, we are becoming like individual neurons in a giant, pulsating hive mind. Science is advancing in wholly new ways and who knows where we will go from here. Thankfully, the balloon will keep expanding into the foreseeable future (until the aliens, robots, or viruses kick our asses back to the stone age, that is). Hooray for technology!