We’ve just seen another study that echoes front-loading. Let’s now consider how a hardcore non-teleological viewpoint would assimilate these findings. Evolutionary biologist Jerry Coyne – who once wrote, “any injection of teleology into evolutionary biology violates precisely the great advance of Darwin’s theory: to explain the appearance of design by a purely materialistic process” – set things up as follows:
One of the key innovations in the history of life—at least, looking back at it from the viewpoint of a complex species—was the origin of multicellularity. Having many cells that are differentiated, so that different cells can do different things, allows the specialization of tissues and organs that opens up many new ways of life…. In their important book The Major Transitions in Evolution, John Maynard Smith and Eörs Szathmáry considered multicellularity one of the nine most critical evolutionary innovations.
So how did multicellularity come about? How much genetic change was needed to get those single cells on their own to form colonies, with some of them specializing in reproduction and the others in locomotion, nutrition, and the like? Did it take a wholesale restructuring of the genome?
In their new paper Prochnik et al. asked a simple question: if we sequence the whole genome of Volvox carteri, how much difference does it show from its fairly close unicellular relative C. reinhardtii? Does the initial evolution of multicellularity require many new types of genes, or will a few simple changes suffice?
The first thing to notice from this introduction is the Missing Duck. That is, where is the guidance from the Duck? Doesn’t it have a preference, expectation, or prediction? Isn’t it willing to place a bet? It would seem not.
In striking contrast, the Rabbit is quite eager to wager.
As readers of my book/blog know, I have long argued that multicellular life was front-loaded. As just one example, on May 7, 2002, I posted this to an internet forum:
My perspective explores the possibility that unicellular organisms were designed in such a way that the evolution of multicellular organisms was made more likely.
And as I explain in The Design Matrix:
Front-loading, by definition, is about designing the future through the present. It is about imposing some kind of constraint on evolution, or more simply put, it is using evolution to carry out design objectives. Since evolution would proceed outward from the originally designed cells, evolution may have been endowed with various sequences and structures to increase the odds that certain future states would be found through a random search stemming outwards from this front-loaded state.
So the Rabbit would lead us to place our bets on the second option. If life was designed in a way to facilitate the emergence of multicellular complexity, we would not expect the need for a wholesale restructuring of the genome along with massive amounts of newly minted genes. And, as Coyne explained, the Rabbit’s expectations played out:
The authors’ conclusion? Not many new genes have to change to turn a single cell into a multicellular, proto-differentiated species. In the Science news piece on this article, plant biologist Arthur Grossman comments: “The findings suggest that it doesn’t take very large changes in gene content to transition from a single-cell to a multicellular lifestyle.”
But now let’s watch how Coyne enables the Duck to absorb these data:
Is this surprising? Well, not really. I’m not sure most biologists would have suggested that multicellularity requires a wholesale restructuring of the types of proteins present in one-celled species. If that were true, it would be very difficult to go from one-cell to multi-cells in an adaptive, step-by-step fashion.
I see. So after we learn it doesn’t take very large changes in gene content to transition from a single-cell to a multicellular lifestyle, it turns out the Duck had a bet on the table all along. And surprisingly enough, it bet on the winner. Or so it seems.
But pay close attention, folks. First of all, while Coyne assures us there is nothing surprising about this finding, consider the words of the people who actually did the research:
Altogether the findings, published in the journal Science, suggest that very limited protein-coding innovation occurred in the Volvox lineage. “We expected that there would be some major differences in genome size, number of genes, or gene families sizes between Volvox and Chlamydomonas,” says Umen. “Mostly that turned out not to be the case.”
It would seem to me that if the researchers expected there would be some major differences in genome size, number of genes, or gene families sizes between Volvox and Chlamydomonas, it would be surprising to find these expectations did not play out.
Second, and more importantly, think about Coyne’s explanation – “If that were true, it would be very difficult to go from one-cell to multi-cells in an adaptive, step-by-step fashion.” Since when is the difficulty of an evolutionary event a defining issue when the heart of Darwin’s theory is likened to Climbing Mt. Improbable? From the non-teleological perspective, difficult things and improbable things happen and they happen all the time. From this perspective, the history of life is a history of lottery winners.
In other words, Coyne’s argument is a teleological argument. “It would be very difficult to go from one-cell to multi-cells in an adaptive, step-by-step fashion” makes sense only if we envision evolution as trying “to go from” one stage “to” another. The whole argument assumes a start and end point, a teleological assumption, yet from a non-teleological perspective, there is no such thing. There is only change and replicators and replicators that change to become more common.
You can know that I am right because if the researchers had found that it took many large changes in gene content to transition from a single-cell to a multicellular lifestyle, Coyne would explain how this too fits nicely within a non-teleological view of evolution. He would certainly not view it as a problem for “Darwin’s theory.”
So in other words, there is nothing surprising about the findings from a teleological perspective which envisions life to be endowed in such a way to facilitate the emergence of multicellular complexity. A view that envisions evolution as trying to get from one point to another by smoothing out some of that “difficult” terrain.
Take away this perspective and we’re left with scientists finding something they did not expect, and non-teleologists trying, after the fact, to smuggle in subtle teleological thinking to rewrite history as if they always expected it. The Duck absorbs all data.
Finally, Coyne ends his analysis with a final observation is music to bunny ears:
It seems, then, that at least this critical step in the original of multicellular species may require not wholesale changes in the types of genes in the genome, but a few critical tweaks in how those genes are expressed.
And let us not forget that the building blocks for all of this rested on things that had already evolved in one-celled organisms, which in themselves are fantastically complex, with elaborate networks of genes for metabolism, excretion, protection, movement, DNA replication, DNA translation into protein, and cell division. Single cells may look simple, but Lord, they’re not!
As one my my colleagues commented after reading this paper, “Maybe all the hard work was done by bacteria.”
Two points come to mind here.
First, all the “hard work” being done by bacteria translates as all the hard work being done very early in evolution. In other words, all the cells found close to the base of the tree of life. Since then, evolution has mostly tweaked and tinkered with what it was handed. And all of this is another way of saying what I wrote in The Design Matrix:
Front-loading is the investment of a significant amount of information at the initial stage of evolution (the first life forms) whereby this information shapes and constrains subsequent evolution through its dissipation. This is not to say that every aspect of evolution is pre-programmed and determined. It merely means that life was built to evolve with tendencies as a consequence of carefully chosen initial states in combination with the way evolution works.
Second, we really need to focus more on bacteria as the hard workers of evolution. And that sounds like another rabbit hole.