Evolution, Morphogenesis & Jean Baptiste Lamarck

Post questions or suggestions here.
Locked
User avatar
Cory Duchesne
Posts: 2320
Joined: Thu Feb 02, 2006 10:35 am
Location: Canada
Contact:

Evolution, Morphogenesis & Jean Baptiste Lamarck

Post by Cory Duchesne »

The following is an excerpt from an interview with Rupert Sheldrake:

Sheldrake: One of the longest and most exhaustive series of experiments in the history of experimental psychology was conducted to test Lamarck's theory that acquired characteristics could be inherited genetically. The tests ran for 34 years, involved thousands of rats on three continents, and in the end disproved Lamarck's ideas. But the results were quite amazing, and would seem to confirm precisely the effects of "morphic resonance" I'm predicting.

The series was begun at Harvard in 1920, by William McDougall, who measured the number of errors his rats made in escaping from a water maze. After twenty generations, his rats were learning over ten times quicker, although he'd bred only the slowest-learning rats to avoid experimental bias. From time to time he also tested untrained rats of the same strain. To his amazement, he found that they, too, were learning very much more quickly. These inexplicable results really threw the biological world into a turmoil when they were published in the 1930's.

One of McDougall's critics was F.A.E. Crew, at Edinburgh University, who duplicated the experiment because he didn't believe it was possible. He used the same breed of standard laboratory rat -- not descended from McDougall's rats. To his surprise, his rats' rate of learning began where McDougall's had left off. Some of them were getting it consistently right the first time. Crew eventually gave up, foxed by these results he hadn't expected and couldn't explain.

A similar series of experiments was then started by W.E. Agar, in Melbourne, who continued them for 25 years. Fifty generations of rats. And he, too, observed much the same result. However, Agar also had an untrained control line of rats which he tested in each generation. He found the same results that McDougall had got: The untrained rats were also getting better and better.

Of course, this demonstrated that whatever effect these men were detecting, it wasn't due to any sort of genetic modification. The final paper came out in 1954 and the biological world breathed a sigh of relief. The textbooks of the 1950's say things like "...as is well known, Agar conclusively discredited McDougall's Lamarckian work on rats", and that seemed to be the end of it. Now it's true they discredited McDougall's conclusions, but they actually reconfirmed his very striking and amazing results. These results, by the way, were never followed up, and they've been lying there in the archives of biology ever since.

Q: Have these effects been observed in other animals?

Sheldrake: They have. The behaviorist B.F. Skinner for many years did experiments in which standard pigeons were trained, using an elaborate and difficult training procedure, to peck at lighted panels in standard "Skinner boxes". In 1961 Brown and Jenkins, who were doing standard Skinner-type pigeon research, noticed that their pigeons immediately cottoned onto pecking at the lighted panels. The whole of this lengthy training procedure was quite unnecessary. The way they wrote up their paper implied that perhaps people had been stupid not to have noticed this before.

Q: How would your M-field theory relate to the theory of evolution as we understand it today?

Sheldrake: The theory of evolution contains three main elements. One is natural selection, which is uncontroversial. But then there's the question of how form and behavior are inherited, and then also of how change, or originality, comes about.

I think my theory helps us see evolution differently in several ways. First, it provides a model of inheritance which allows for the passing on of acquired characteristics without genetic modification. So you could have more rapid learning by whole species.

Secondly, it means that we can think of effects in evolution where one species, through some change that "jolts" its tuning system, tunes into the fields of another species quite distant in space. I think that would help to account for some puzzling evolutionary convergences and parallelisms. In Australia, for example, the marsupials have evolved parallel forms to dogs, mice and many other mammalian types that occur elsewhere.

The theory also predicts that the M-fields of long-extinct species should still be around, and through these kinds of tuning shifts sufficiently similar species could pick up some of their characteristics. It's quite an amazing thought, really, but think again of the television analogy: destroying a TV receiver wouldn't have the slightest effect on the broadcasting station. If you look into the literature on teratology -- the study of freaks and monstrosities -- you find numerous examples of mutant types called atavisms, or reversions to remote ancestral forms. Examples would include three-toed horses, and human babies born with tails.

Now these tuning shifts may come about through changes in the DNA, but they may also be due to environmental effects which involve no genetic changes at all. For example, if you take fruit fly eggs about three hours old and expose them to ether for an hour, a significant portion of them will produce not the usual two-winged fruit fly, but four-winged flies resembling the ancestors of this group of insects which existed tens of millions of years ago. And, interestingly, the more this experiment is performed, the greater the proportion of mutants to normal flies.

When we come to the question of the creation of new fields, we're right back on the borderline of science and philosophy where you'll never get clear agreement anyway. The materialists will say all innovation must be due to chance mutations and the nonmaterialists would say there's a creative factor underlying nature and guiding these things. Natural science -- and this includes my own hypothesis -- deals with regularity or repetition in nature, not originality or creativity, so from a scientific point of view this will always remain a wide-open question.
I think the challenge for biologists is reconciling the element of Random variation in Darwinian natural selection with the sort of Evidence fueling Sheldrake's theories.

As for Lamarck, his theory I do believe has no evidence supporting it. However, I can understand how someone might consider Sheldrake's interests as having a bit of a Lamarkian spirit.

The evidence perhaps suggest that there is something more than just natural selection that is responsible for the refinement of humanity, and I can see how some might regard it as Lamarkian, or perhaps there is just a more esoteric form of natural selection happening on an underlying level of implicit information, even further hidden then the well understood genetic information.
Locked