Lamarkism, Revisited

[SuuT]

The Sins of the Fathers, Take 2
At tributes to Darwin, Lamarckism—inheritance of acquired traits—will be the skunk at the party.

Sharon Begley
NEWSWEEK
From the magazine issue dated Jan 26, 2009

Alas, poor Darwin. By all rights, 2009 should be his year, as books, museums and scholarly conclaves celebrate his 200th birthday (Feb. 12) and the 150th anniversary of "On the Origin of Species" (Nov. 24), the book that changed forever how man views himself and the creation. Teamed with genetics, Darwin's explanation of how species change through time has become the rock on which biology stands. Which makes the water flea quite the skunk at this party.

Some water fleas sport a spiny helmet that deters predators; others, with identical DNA sequences, have bare heads. What differs between the two is not their genes but their mothers' experiences. If mom had a run-in with predators, her offspring have helmets, an effect one wag called "bite the mother, fight the daughter." If mom lived her life unthreatened, her offspring have no helmets. Same DNA, different traits. Somehow, the experience of the mother, not only her DNA sequences, has been transmitted to her offspring.

That gives strict Darwinians heart palpitations, for it reeks of the discredited theory of Jean-Baptiste Lamarck (1744–1829). The French naturalist argued that the reason giraffes have long necks, for instance, is that their parents stretched their (shorter) necks to reach the treetops. Offspring, Lamarck said, inherit traits their parents acquired. With the success of Darwin's theory of random variation and natural selection, Lamarck was left on the ash heap of history. But new discoveries of what looks like the inheritance of traits acquired by parents—lab animals as well as people—are forcing biologists to reconsider Lamarckism.

The lab mice, of course, came first. Since 1999 scientists in several labs have shown that an experience a mouse mother has while she is pregnant can leave a physical mark on the DNA in her eggs. Just to emphasize, this is not a mutation, the only way new traits are supposedly transmitted to children. Instead, if mother mouse eats a diet rich in vitamin B12, folic acid or genistein (found in soy), her offspring are slim, healthy and brown—even though they carry a gene that makes them fat, at risk of diabetes and cancer, and yellow. It turns out that the vitamins slap a molecular "off" switch on the obesity/diabetes/yellow-fur gene. (Don't try this at home: no one knows which human genes soy, B12 and folic acid might silence.) This was the first evidence, now confirmed multiple times, that an experience of the mother (what she eats) can reach into the DNA in her eggs and alter the genes her pups inherit. "There can be a molecular memory of the parent's experience, in this case diet," says Emma Whitelaw of Queensland Institute of Medical Research, who did the first of these mouse studies. "It fits with Lamarck because it's the inheritance of a trait the parent acquired. There is even some evidence that the diet of a pregnant mouse can affect not only her offspring's coat color, but that of later generations."

Inheriting a DNA-silencing mark that your mom acquired is not as dramatic as giraffes passing on elongated necks to their kids. And the new Lamarckism doesn't mean that human moms who work out will pass along toned abs to their children, or that human dads who dye their hair red will have red-haired children. But preliminary evidence suggests that Lamarckism acts in people, too. In 2005, scientists in London found that the grandsons of men who had abundant food when they were boys (the study was done on men in a small town in northern Sweden) were much more likely to have diabetes and to die an early death than were the grandsons of men who suffered food shortages as boys. A 2006 study by the same scientists found that when fathers smoked as young boys, their sons tended to be more obese than did the sons of men who did not smoke as boys. Similar to the lab mice, the experience of the parents is visited upon the children and even the grandchildren. If the results hold up, says Whitelaw, "it would signal a paradigm shift in the way we think about the inheritance" of traits.

The existence of this parallel means of inheritance, in which something a parent experiences alters the DNA he or she passes on to children, suggests that evolution might happen much faster than the Darwinian model implies. "Darwinian evolution is quite slow," says Whitelaw. But if children can inherit DNA that bears the physical marks of their parents' experiences, they are likely to be much better adapted to the world they're born into, all in a single generation. Water fleas pop out helmets immediately if mom lived in a world of predators; by Darwin's lights, a population of helmeted fleas would take many generations to emerge through random variation and natural selection. The new Lamarckism promises to "reveal how the environment affects the genome to determine the ultimate traits of an individual," says Whitelaw.

Some of these studies will not hold up, as is typical with revolutionary new science. And resistance to what is being dubbed "the renaissance of heresy" is firm; one scientist called a paper on this stuff "a misguided attempt at scientific humor." But evidence for the new Lamarckism is strong enough to say the last word on inheritance and evolution has not been written.

http://www.newsweek.com/id/180103/output/print



The implications are truly staggering.

I remember getting into a very heated debate in grad. school with a professor (he was the department chair, in fact) over the chasm that exist(ed) in Modern Synthetic Evolutionary Theory that only Lamarkism could fill. He, and nearly everyone in the class, thought that my stance was scientifically blasphemous; and some just laughed hysterically.

[Beorn]

The French naturalist argued that the reason giraffes have long necks, for instance, is that their parents stretched their (shorter) necks to reach the treetops.

I had to laugh at that one, because as a child, and before I had even a clue to who Darwin, or evolution, or even Lamarck were; I often made that same assumption.

[SuuT]

I had to laugh at that one, because as a child, and before I had even a clue to who Darwin, or evolution, or even Lamarck were; I often made that same assumption.

Here's the thing. Even though the author of the article takes a very reserved tone, and even pokes fun at the idea originally proposed by Lamark, we must read between the lines of 'self-censorship' and not take the article as a given objectivity.

Via logic, the implications are clear: if some water fleas sport a spiny helmet that deters predators; and others, with identical DNA sequences, have bare heads, and what differs between the two is not their genes but their mothers' experiences; then, by lateral extension, giraffes can, indeed, pass on a longer neck for no other reason than the environmental need for one.

Exciting, isn't it! - to have "gut feeling" verified, that is.



The first implication for Humans that comes to mind; and futher - Race - is that struggle and situational impetus, and how we (and how our forebears) have/do respon(ded), alters us in either positive or negative ways relative to our aims. As a specific example, there is no reason for thinking that constantly pushing the/one's body to novel challenges will not result in hypertrophy of the offsping; and, there is no reason to think that a constant struggle with the intellect will not offer-up new, and profound, opportunities of advancement for offspring.

The conclusion is clear as day: struggle, strife, challenge, competition, etc., are necessary for the advancement of the type 'Man'.

That which does not kill me, makes me stronger. - Nietzsche

[Lyfing]

For a while now I've had a notion that mythology does things with us along these lines..

In a nutshell..there are IRM's that respond to sign stimuli..

Students of animal behavior have coined the term "innate releasing
mechanism" (IRM) to designate the inherited structure
in the nervous system that enables an animal to respond thus to
a circumstance never experienced before, and the factor triggering
the response they term a "sign stimulus" or "releaser." It is obvious
that the living entity responding to such a sign cannot be
said to be the individual, since the individual has had no knowledge of the object to which it is reacting. The recognizing
and responding subject is, rather, some sort of trans- or superindividual,
inhabiting and moving the living creature.

Primitive Mythology, Pages 30-31

Chicks with their eggshells still adhering to their tails dart for
cover when a hawk flies overhead, but not when the bird is a gull
or duck, heron or pigeon. Furthermore, if the wooden model of a
hawk is drawn over their coop on a wire, they react as though
it were alive unless it be drawn backward, when there is no response.
Here we have an extremely precise image never seen before,
yet recognized with reference not merely to its form but to its
form in motion, and linked, furthermore, to an immediate, unplanned,
unlearned, and even unintended system of appropriate
action: flight, to cover. The image of the inherited enemy is already
sleeping in the nervous system, and along with it the wellproven
reaction. Furthermore, even if all the hawks in the world
were to vanish, their image would still sleep in the soul of the
chick never to be roused, however, unless by some accident of
art; for example, a repetition of the clever experiment of the
wooden hawk on a wire. With that (for a certain number of generations,
at any rate) the obsolete reaction of the flight to cover would
recur; and, unless we knew about the earlier danger of hawks to
chicks, we should find the sudden eruption difficult to explain.
"Whence," we might ask, "this abrupt seizure by an image to
which there is no counterpart in the chicken's world? Living gulls
and ducks, herons and pigeons, leave it cold; but the work of art
strikes some very deep chord!"

Primitive Mythology, Page 31

Then there is Supernormal Sign Stimuli which is beyond regular sign stimuli..

It was found, for instance, that the male of a certain butterfly
known as the grayling (Eumenis semele), which assumes the initiative
in mating by pursuing a passing female in flight, generally
prefers females of darker hue to those of lighter and to such a
degree that if a model of even darker hue than anything known in
nature is presented, the sexually motivated male will pursue it in
preference even to the darkest female of the species.
"Here we find," writes Professor Portmann, in comment, "an
'inclination' that is not satisfied in nature, but which perhaps, one
day, if inheritable darker mutations should appear, would play a
role in the selection of mating partners. Who knows whether such
anticipations of particular sign stimuli may not play their part in
the support and furthering of new variants, inasmuch as they
may represent one of the factors in the process of selection that
determines the direction of evolution?"

Primitive Mythology, Page 43

Mythology is this Supernormal Sign Stimuli..

Obviously the human female, with her talent for play, recognized
many millenniums ago the power of the supernormal sign
stimulus: cosmetics for the heightening of the lines of her eyes have
been found among the earliest remains of the Neolithic Age. And
from there to an appreciation of the force of ritualization, hieratic
art, masks, gladiatorial vestments, kingly robes, and every other
humanly conceived and realized improvement of nature, is but a
step or a natural series of steps.

Evidence will appear, in the course of our natural history of the
gods, of the gods themselves as supernormal sign stimuli; of the
ritual forms deriving from their supernatural inspiration acting as
catalysts to convert men into gods; and of civilization this new
environment of man that has grown from his own interior and has
pressed back the bounds of nature as far as the moon as a distillate
of ritual, and consequently of the gods: that is to say, as an
organization of supernormal sign stimuli playing on a set of IRMs
never met by nature and yet most properly nature's own, inasmuch
as man is her son.

Primitive Mythology, Pages 43-44

And we change accordingly to our ancestors experiences with all this..and pass it on through our own..

Nor are we ready, yet, to say whether the obvious, and sometimes
very striking, physical differences of the human races represent
significant variations of their innate releasing mechanisms.
Among the animals such differences do exist in fact, changes in
the IRMs of the major instincts appear to be among the first
things affected by mutation.

For example, as Tinbergen observes:

The herring gull (Larus argentatus) and the lesser blackbacked
gull (L. fuscus) in north-western Europe are considered
to be extremely diverged geographical races of one
species, which, having developed by geographical isolation,
have come into contact again by expansion of their ranges.
The two forms show many differences in behavior; L. fuscus
is a definite migrant, traveling to south-western Europe in
autumn, whereas L. argentatus is of a much more resident
habit. L. fuscus is much more a bird of the open sea than
L. argentatus. The breeding-seasons are different. One behavior
difference is specially interesting. Both forms have two
alarm calls, one expressing alarm of relatively low intensity,
the other indicative of extreme alarm. L. argentatus gives the
high-intensity alarm call much more rarely than L. fuscus. The
result is that most disturbances are reacted to differently by
the two forms. When a human intruder enters a mixed colony,
the herring gulls will almost always utter the low-intensity call,
while L. fuscus utters the high-intensity call. This difference,
based upon a shift of degree in the threshold of alarm calls,
gives the impression of a qualitative difference in the alarm
calls of the two forms, such as might well lead to the total disappearance
of one call in one species, of the other in the
second species, and thus result in a qualitative difference in
the motor-equipment. Apart from this difference in threshold,
there is a difference in the pitch of each call.13

Between the various human races differences have been noted
that suggest psychological as well as merely physiological variation;
differences, for example, in their rates of maturing, as Geza
Roheim has indicated in his vigorous work on Psychoanalysis and
Anthropology. 14 However, it is still far from legitimate, on the
basis of the mere scraps of controlled observation that have been
recorded, to make any such broad generalizations about intellectual
ability and moral character as are common in discussions of this
subject. Furthermore, within the human species there is such broad
variation of innate capacity from individual to individual that generalizations
on a racial basis lose much of their point.

Primitive Mythology, Pages 45-46

Later,
-Lyfing