In the last post I pointed out that the biggest problem trying to communicate about evolutionary history is that transformational evolution is much easier to grasp than is variational evolution. A linear sequence can be understood almost instantly but a branching sequence cannot, because it is an inter-linked set of linear sequences. People have a preference for simplified stories with unambiguous beginnings and ends. Unfortunately, variational evolution is a process of continual branching and extinction, apparently without end, whereas transformational evolution is a simple linear process, usually leading to a predictable end.
This has important consequences for communication among evolutionists, and between evolutionists and the general public. For example, while I have no intention of entering the debate between evolutionists and creationists, it seems to me that there is a lot of talking but not a lot of communicating between these two groups. In this post I will argue that a lot of the problem is sloppy communicating on the part of the evolutionists.
This can have two aspects: (a) sloppy language (ambiguous use of words), and (b) sloppy diagrams (poor choice of iconography). I think that evolutionists have been guilty of both of these things. In this post I will discuss words, and in subsequent posts I will cover pictures.
In order to make contact with an audience you have to communicate on their terms. Using language that can have two meanings, no matter how subtle that difference may seem to you, will result in failure, at least some of the time. You have to see the other person's point of view clearly, and then express yourself in words that will address that point of view, rather than assuming that your own point of view will be obvious.
For example, the simple claim that "humans evolve" will always be ambiguous, because "humans" can refer to both the species and the individuals within that species, and "evolution" can be applied to both of them, but with very different meanings. For individuals, evolution is transformational, while for species evolution is variational. So, exactly what does the statement "humans evolve" mean? The speaker/author may mean one thing, but we would all be perfectly justified in interpreting it very differently from that intention.
I was inspired to write this blog post by reading the introduction to Daniel Fairbanks' recent book Evolving: the Human Effect and Why it Matters (Prometheus Books, 2012), in which he says: "Along with the rest of life, we evolved and we are evolving." One can interpret this sentence as "You and I evolve through time", or as "The human species evolves through time". I assume (hope?) that the author means the latter, but everyone (including creationists) could be excused for reading the former, and thus possibly dismissing the author's idea.
Any statement made by an evolutionist that leaves itself open to this sort of dual interpretation is simply perpetuating the problem caused by the two meanings of the word "evolution".
I do not intend "to pillory the few for errors which many commit with impunity" (to quote Björn Andersen, Methodological Errors in Medical Research: an Incomplete Catalogue, 1990), and so singling out Daniel Fairbanks is perhaps unfair. However, if a professional geneticist can leave himself open to this sort of simple (but profound) misinterpretation when trying to communicate with the general public, then we can easily see that there is a fundamental problem: the evolutionists are assuming a lot about the meaning of their words that is not necessarily assumed by the general public.
In Darwinian biology, species evolve not individuals. Transformational change in individuals is called "development" or "ontogeny" rather than "evolution". Thus, I do not evolve, and I am not descended from a monkey; and yet my species has evolved over a long period of time, and I share rather a lot of ancestors with the monkeys. These distinctions seem quite clear to an evolutionist, and yet the language used by evolutionists frequently fails to clearly distinguish between them, to the great detriment of communication.
In a similar vein, in a 2011 press release from the highly respected journal PLoS Biology, Peter Currie, a developmental biologist at the Australian Regenerative Medicine Institute, is quoted as saying: "Humans are just modified fish. The genome of fish is not vastly different from our own." Clearly, the first statement is nonsense, although the second one is quite correct. The only fish whose genomes we know about are extant not extinct. We share an ancestor with these fish, and our genomes are similar because we both inherited our genomes from that ancestor. However, the ancestor was not a fish, and thus we are not modified fish, any more than fish are modified humans. We are both modified from our common ancestor — both fish and humans share characteristics with that ancestor, but they differ from that ancestor (and from each other).
Sadly, professionals also engage in mis-communication when trying to communicate with each other. I won't indulge in a detailed discussion here, but there are at least two misleading expressions that one very commonly encounters in the professional literature: "basal branch of the tree", and "derived species". The first expression is used to refer to an unbranched lineage arising near the common ancestor, when compared to a more-branched lineage. For example, in the diagram below we might say that taxon A is on a "basal branch", whereas taxon B is not. But, how can one lineage be more basal than another? After all, both lineages connect to the "base" at the same point. To claim that one is basal and the other not is like saying that one brother is more basal than another in a family tree just because he has fewer children! The second expression refers to a species that has more "derived" characters than another. For example, in the diagram we might say that taxon B is more derived than taxon A. Characters change from ancestral to derived through time (eg. scaly skin covering is ancestral while fur is derived, because the latter arose later in time). However, this does not make any species more derived. It is the characters that are derived not the species — each species has a combination of ancestral characters and derived ones (including humans) .
Hanno Sandvik (Tree thinking cannot taken for granted: challenges for teaching phylogenetics. 2008, Theory in the Biosciences 127: 45–51) has noted another aspect of potential mis-communication among professionals in phylogenetics — the semantics of language differences. He points out that some languages (eg. German, Swedish, Norwegian) have a specific word for referring to genealogical relationship whereas English does not:
"The German word for 'relationship' is 'Verwandtschaft', but while the English word has all kinds of abstract and symbolic connotations, including overall similarity, the German term is reserved for true, genealogical bonds."
This simplifies communication in the one language by being unambiguous, whereas ambiguity is a potential problem in the other language. Sandvik comments that historically this semantic difference has created all sorts of mis-communication among English speakers, each of whom has had their own idea about what "relationship" means.
I suppose that I would be remiss not to point out that mis-communication works both ways between evolutionists and the general public, although that is not my main thesis here. Constance Clark (Evolution for John Doe: pictures, the public, and the Scopes Trial debate. 2001, The Journal of American History 87: 1275-1303) noted that:
"the most dramatic event at the Scopes trial of 1925 occurred when William Jennings Bryan announced, incredibly, that he was not a mammal ... The trial transcript shows that Bryan did not precisely deny his place within the zoological class Mammalia. He did, however, emphatically object to a diagram that located humans among the mammals ... For scientists this was a version of a familiar branching diagram depicting natural relationships. From Bryan’s point of view it seemed to mock traditional verities about human significance."
Bryan's point of view was not well expressed by denying being a mammal, and would be better expressed as a claim that humans have extra characteristics not shared with other mammals (such as what he referred to as "an immortal soul"). After all, this is apparently what he meant by his statement — humans may have mammalian bodies, but there is more to them than that.
Henshaw Ward (Evolution for John Doe, 1925) expressed what seems to me to be the typical attitude of evolutionists:
"the average man ... thinks evolution is 'the doctrine that man is descended from monkeys', and he is so amused or offended at this theory that his whole mind is occupied with it. His conception is ridiculously false. Until John Doe discards that notion and takes a fresh start, he will never understand the subject."
As I have suggested here, asking the readers to change their attitude is a futile request unless the writers first undertake to change their own attitude, and to write unambiguously.