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In “Cancer and Evolution: Amplification” my 1984 Letter in Journal of Theoretical Biology I make clear my conviction that cancer did not occur in every multicell lineage:
"[Oncogenes have] the potential for killing the organism in whose genetic program they are present, such deaths being initiated by the occurrence of a mutational event in a single somatic cell. This theory states that oncogenes, thus defined, have been present in every cell of every specimen of every species of the Bilateria that ever existed, and that they have existed nowhere else in nature. " (Emphasis added)
The journal's Reviewer Number One takes a completely different view. As I wrote in my emailed letter to the journal’s editor:
“Reviewer #1 is clearly convinced that cancer can in principle occur in any multicell, that the initiation of the process does not require a specific triggering mechanism. He ignores the work of Varmus and Bishop (which earned a Nobel in 1985) and others in identifying cellular oncogenes, cancer-triggering mechanisms. I have already commented on the problems those discoveries create for conventional evolution theory.”
“Number One also suggests that if only they were examined more closely Cnidarians like jellyfish might exhibit cancer. My contrasting conclusion, inferred from their 500 million years of naked sun-bathing, is that death from carcinogenic UV radiation never threatened the jellyfish lineage. His preference for observational science and his rejection of inferential logic reminds me of the dozy bint I encountered who insisted that a certain 19th Century naturalist erred in concluding that direct observation was not a sufficient means of gaining insights into the history of extant animals.”
To summarize the critical distinction between me and the reviewer as to how the question “Was the jellyfish lineage influenced by cancer selection?” ought to be addressed:
James Graham: Using inferential logic, their ~500 million year history of unshielded exposure to carcinogenic UV radiation is sufficient to conclude that their evolution was unaffected by cancer.
Reviewer Number One: Ignore evolutionary history and do not use inferential logic. Simply observe enough extant jellyfish specimens long enough and cancer might be detected.
I have read enough of the writings of professionals in the biological sciences to know that many are convinced that there is only one scientific method; they seldom employ inferential logic and rely solely on laboratory investigation or direct observation in nature. But why would a scientist holding such narrow views undertake review of a paper submitted to a journal devoted to the historical science of evolution, a paper written by someone whose peer-reviewed published theory is the result of the same methodology he employs in the submitted manuscript?
Note 1: In considering the question of “Which animals can get cancer?” I did not ignore observational science. I consulted, among other works, the Cancer Institute’s Monograph 31 Neoplasms and Related Disorders in Invertebrates and Lower Vertebrate Animals, a 767-page tome co-authored by the then Director of the Registry of Tumors in Lower Animals.
Note 2: As I pointed out in my emailed letter to the journal editor, serious investigators do not, as proposed by his reviewer, passively observe specimens to determine their susceptibility to cancer. They inoculate them with carcinogens. For example, printed on page 63 of Monograph 31 is a table summarizing several efforts to initiate cancer in echinoderms, some of them as early as the 1930s and, more recently, Israeli investigators have inoculated blind mole rats.
Comments and questions to the author ... are welcomed here.
At this site you will find links to additional material including my original Letters to the Journal of Theoretical Biology and the 1992 Nature review of my book.
This page was archived at The WayBack Machine on April 20, 2015.
