TomboyMom

Other than the fact that in real life there is no Lamarckism. Yes, this is the mechanism that you haven't described. How does the trait get from the organism's phenotype to its genotype?

Elijah

You are going to have a local reaction before you have a systematic one. The body's circulation system is built to work by reflex on a local level to control temperature. Maintaining the core temperature is a more complex problem because the body can take a lot of steps to prevent over heating or over cooling; not just sweating and shivering. From altering pressure/vaso dialation to slowing and speeding of your breathing.

dlawbailey

....EVERY one of your arguments.

Talks about a "physical change" in an organism in response to stimuli. This is trivially true. It's completely agreed upon. But where does it play a role in the mechanism of reproduction?

You know where babies come from, I assume. And you know that to produce babies a reasonably small portion of a reasonably simple sperm cell is released into the egg.

And THAT and that alone is what makes the baby. So the question is this: how is the "information" of the animal's history of stimuli translated from sperm to egg during that exchange?

In terms of modifying DNA, DNA gets modified all the time. It gets coiled and super-coiled and slightly less supercoiled, in response to many things. But in higher animals there is little or no evidence of any systematic alteration of the code.

Now E. coli are a different story. When I read the experiment you first described I immediately thought "Wow, plasmids are cool."

Because E. coli colonies SHARE and re-combine strings of their genome extremely easily. Thus at the colony level, traits can be "bred in" and "bred out" quite easily.

But mammals don't have plasmids and so you would have to make an argument for a novel translation vector. But you don't.

show_no_mercy

It would be relatively easy for Elijah to prove his point. Just sequence a genome of a person who is in a normal lab condition. Then sequence their genome when they're put in one of Elijah's "lamarckism" scenarios. If there's no difference in which genes are expressed and which ones aren't, then Lamarckism is false.

Why, oh why, hasn't this simple experiment been conducted yet, I wonder?

scombrid

Only if the organism already has the programming for this capacity.

The gametes aren't changed.

My sperm don't know that the capillary beds in my muscles have expanded or that my heart is slightly enlarged due to prolonged athletic training. Unless they get it from their mother, my offspring will have no more capacity to adapt to athetic stress than my body has now. Can you demonstrate the way that my germ cells are supposed to be altered by my somatic response to the environment?

The capacity to adapt to the environment is heritable. The specific phenotypic expression of that capacity is not.

Faid

OK... So, I'm not sure in which thread I should post this, since it's relevant to both this and the "long-living patriarchs" one. I decided to post it here, but the mods should feel free to move it if they believe it belongs elsewhere.

Elijah, I have a question- a genuine question, not trying to point out an inconsistency or anything.

You say that you are a Lamarkian. You also seem to believe that Humans had amazingly long lifespans in the past.

My question is, what is the Lamarkiam mechanism that created those extraordinary long lifespans in humans?


Such a unique trait should be strongly "selected" for to emerge- what is your proposed method?

Vicious Love

I'm more interested in how they lost that ability. Did they all get murdered or buried under rockslides or whatever in their early years, before they got around to practicing longevity? Or did they just spend the centuries practicing dying, until they finally got good at it?

Nialler

It's The Fall, don't ya know. The Fall, I tells ya.

Elijah

For the stimuli causing genetic changes/expression.

http://en.wikipedia.org/wiki/Signal_transduction

Something about gene expression

http://en.wikipedia.org/wiki/Gene_expression

Something about epigenetics.

http://en.wikipedia.org/wiki/Epigenetics

Cell communicating genetic information

http://en.wikipedia.org/wiki/Cell_signaling

http://en.wikipedia.org/wiki/Notch_signaling

http://en.wikipedia.org/wiki/Morphogenesis

show_no_mercy

This is why you answered my ERV question wrong, and why you don't have any idea about reproduction. In order for any trait to be passed on, it has to affect the gametes. That's why I didn't tell you the answer, because if you actually knew what you were talking about, "affecting the gametes" would've been the first words you posted.