I. Miracles and Monsters

What is going on with life? It is utterly amazing all the things these plants and creatures of mother nature do! Their beauty! Their complexity! Their diversity! Their ability to sustain themselves! The symbiotic relationships! Where did it all come from? If evolution is the right idea, how does it work? We’re not talking about the little changes, the gradual changes proposed by Charles Darwin. We understand there is natural selection going on, like pepper colored moths and Darwin’s finches. We’re talking about the big changes – the evolutionary leaps apparently due to mutations affecting gene expression, a process known as saltation. How do these mutations know what will work – shouldn’t there be a bunch of failed abominations everywhere from the gene mutations that screwed up? Shouldn’t a mix up be far more likely than an improvement? Is it possible mutations are adaptive as Jean-Baptiste Lamarck, a predecessor of Darwin, originally proposed? That is, could it be that the environment, rather than random changes, is the primary driver of adaptation?

 

Imagine selecting architectural plans on a two-story house. Suppose we randomly pick from the existing set of millions of blueprints for the upstairs, and separately pick the plans for the downstairs and put them together. How many times would you expect this house to be functional? The plumbing and electrical systems to work? Suppose we start with a blueprint for a house and then select randomly the plans for just the living room and swap that into the original? What are the chances this would produce a final blue print that was workable? Seemingly very small we should say! We expect there should be all these monstrous houses, with leaking plumbing, short circuited electricity, windows looking out at walls, doorways to nowhere, and grotesque in style!

 

Turns out Evolutionary Biologists have been concerned with this problem for a long time. A geneticist named Richard Goldschmidt was the first scientist to coin the term “hopeful monster” in 1933 in reference to these abominations. Goldschmidt’s theory was received with skepticism. Biologists argued: if evolution did produce big changes in a species then how would these mutants find a mate? For most of the 20th century Goldschmidt’s ideas were on the back burner, scientists were focused on gradualism as they uncovered many examples of gradual evolutionary changes in nature, supporting the natural selection hypothesis. But, recent scientific results reveal the environment does, indeed, have a deep impact on the traits of offspring. The adaptations of embryos in experiments are an example:

 

“The past twenty years have vindicated Goldschmidt to some degree. With the discovery of the importance of regulatory genes, we realize that he was ahead of his time in focusing on the importance of a few genes controlling big changes in the organisms, not small-scales changes in the entire genome as neo-Darwinians thought. In addition, the hopeful monster problem is not so insurmountable after all. Embryology has shown that if you affect an entire population of developing embryos with a stress (such as a heat shock) it can cause many embryos to go through the same new pathway of embryonic development, and then they all become hopeful monsters when they reach reproductive age.” – Donald R. Prothero in his book Evolution: What the Fossils Say and Why it Matters (2007); via rationalwiki.org.

These discoveries prompted Evolutionary Biologist Olivia Judson to write a wonderful article “The Monster is Back, and it’s Hopeful.” (via Wikipedia) Still, we are left wondering: where are all the hopeless monsters? All the embryos either adapt to the stress or keep the status quo – there are no failures. Shouldn’t some suffer crippling mutations? Are epigenetic factors involved? And, perhaps most importantly, even with environmental feedback, how do organisms know how to adapt – i.e. how is the process of adaptation so successful?

 

The puzzle would not be complete, however, without also considering some amazing leaps that have occurred along the tree of life, for example, the mutations that lead to the evolution of the eye. How does life figure out it can construct this extended precisely shaped object – the eyeball – and set up the lens, the muscles to focus it, the photoreceptors and the visual cortex to make sense of the image? It seems like we would need a global plan, a blueprint of an eye, before we start construction! Not only that, but to figure it out independently at least fifty-times-over in different evolutionary branches? Or, how did cells make the leap from RNA to DNA, as is widely believed to be the case, in the early evolution of single celled organisms? Evolutionary biologists puzzle that to make that leap life would need to know the DNA solution would work before it tried it. How should life be so bold – messing with the basic gene structure would seem fraught with danger? How could life know? And, don’t forget, perhaps the most amazing leap of all, where does this amazing human intelligence come from? We humans, who are probing the origins of the Universe, inventing or discovering mathematics, building quantum computers and artificial intelligence, and seeking to understand our very own origin– however it may have happened – how did WE come to be?

 

To frame the problem, let’s talk classical statistics for a second and consider the following situation: suppose we have 100 buckets into which we close our eyes and randomly toss 100 ping pong balls. Any that miss we toss again. When we open our eyes, what distribution should we expect? All in a single cup? Probably not. Scattered over many cups with some cups holding more ball than others? Probably something like that. If we repeat this experiment zillions of times, however, sooner or later, we will find one instance with them all in the same bucket. Is this a miracle? No, of course not. Once in a while amazingly unlikely things do happen. If we tossed the balls repeatedly and each time all landed in the same bucket, now that would feel like a miracle! That’s what’s weird about life – the miracles seem to keep happening again and again along the evolutionary tree. The ping pong balls appear to bounce lucky for Mother Nature!

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