Can environment influence heredity?

[flatearthsurvivor]

I know this is heretical to some, but I can't help but wonder if the discounted theory that NOTHING can be inherited by offspring because of environmental factors encountered or endured by their parents.

For instance, we now know that near starvation endured by people before conceiving can affect the biology of their grandchildren.

I doubt if many experiments are done on this subject because science has "known" for over a hundred years that Lemarck was "wrong."

As a layman, however, I'm not as certain he was wrong in ALL instances, as now there have been findings that food deprivation can affect the biology of grandchildren.

Does anyone know, for example, if any studies have been done to determine if the blood of the offspring of horses that have been injected with venom (to supply antidotes) exhibit ANY difference in THEIR immunity to snake venom in comparison to offspring of horses that have NOT been injected with venom?

I appreciate in advance a reply by anyone who has a working KNOWLEDGE of this subject because I already know what the scientific literature over the last hundred years has to say on the subject.

I simply have my doubts as to its accuracy.

[flatearthsurvivor]

s/b "... but I can't help but wonder if the discounted theory that NOTHING can be inherited by offspring because of environmental factors encountered or endured by their parents is flawed."

[safeleo]

Although I am not certain, I'm pretty sure animals don't create "antidotes" to venom at all. Perhaps you mean develop immunity to certain diseases? In that instance, yes, animals can pass on their gained immunity to their offspring, by passing on their antibodies. The problem with Lemarck's theory was that it was made before anyone had even thought of DNA. Animals can't actively change their DNA, and that's the stuff that gets passed onto their offspring. For example, if you work out, your children won't have a higher muscle mass than anyone else's children. In cases of starvation, changes might have come about because the parents were too weak and nutrient deprived to provide for their children, causing starvation in the child as well.

[BioWizard]

Organisms can pass on some environment-induced changes to their offspring. This occurs due to two reasons:

1- DNA can be covalently modified (small molecular groups can be attached to it)
2- Environmental factors can affect the enzymes that modify DNA
3- These modifications can become (imprinted), and then passed on to the DNA of the offspring

So while the changes do not alter the DNA sequence per say, they alter the way it is "decorated" by little molecules such as methyl and acetyl groups. Since these decorations can affect how genes are expressed, modifying them can have biological effects.

These phenomena are studied in epigenetics.

The question, however is whether such changes are necessarily adaptive. While we can't tell for sure yet, some of these changes appear to have an adaptive value, while others don't. It is likely that examples which produce an adaptive outcome (i.e. somehow make the offspring better prepared to cope with the environmental conditions that caused the epigenetic changes in the parents) will be selected for, while others will just "drift" away. So far, however, adaptive examples of epigenetic impriting are rare, and are almost insignificant compared to adaptive changes in the DNA code (all lifeforms considered). It's probably due to the fact the genomes (just DNA) have been evolving much longer than epigenomes (DNA + the molecules that attach to it + enzymes that catalyze this). Maybe over time, this system will be further tuned by evolution to allow robust adaptive responses in offspring in response to environmental stresses experienced by the parents.

[Braininvat]

Tortoiseshell cats - that's an epigenetic effect, isn't it? Every torty I've known or heard about from a torty owner, has had personality problems (i.e. cranky and/or skittish). Same goes for calico.

[Don Juan]

Gradually becoming part of that influential environment are rational beings or similar systems increasing in knowledge to alter heredity.

[littletrio]

In the late eighties, I read a article from Discover Magazine on DNA switching and have contemplated its possible effects on humans. We now know that the cells receptors pick up the sense data/hormones, e.g., letting the information into the cell and manipulate the encompassed cellular DNA. The sense data/hormones taken in (as a register of environment) will transcend into inherent adaptive (blueprint/dna). But, this will only effect the potential offspring and must be passed down.

Bruce Lipton, has done some exciting research on epigenetics over the last 35 years. He has a heart of gold and is a freaking genius......check out a few youtube videos of his work.

Rupert Sheldrake, has been working on Morphogenetic Resonance for decades, too. Great stuff, i.e., the resonance of the herd actually helping develop the embryo. Have often pondered if the Earths constants are manipulated by Gaia's Resonance to adapt to the entropy of humans. Who knows? But, good stuff regardless. Rupert's new book "Science set Free" kicks arse.

[flatearthsurvivor]

I am not a scientist. I know little more about DNA and the influences that contribute to biological imperatives, propensities and compositions than the average layman.

However, I am intrigued by the possibility that environmental factors can influence the biological "makeup" of offspring. I believe there is much that contemporary geneticists and biologists have to learn about the mechanisms that influence the evolution of our and every other species.

[doogles]

Organisms can pass on some environment-induced changes to their offspring. This occurs due to two reasons:

1- DNA can be covalently modified (small molecular groups can be attached to it)
2- Environmental factors can affect the enzymes that modify DNA
3- These modifications can become (imprinted), and then passed on to the DNA of the offspring

So while the changes do not alter the DNA sequence per say, they alter the way it is "decorated" by little molecules such as methyl and acetyl groups. Since these decorations can affect how genes are expressed, modifying them can have biological effects.

These phenomena are studied in epigenetics.

The question, however is whether such changes are necessarily adaptive. While we can't tell for sure yet, some of these changes appear to have an adaptive value, while others don't. It is likely that examples which produce an adaptive outcome (i.e. somehow make the offspring better prepared to cope with the environmental conditions that caused the epigenetic changes in the parents) will be selected for, while others will just "drift" away. So far, however, adaptive examples of epigenetic impriting are rare, and are almost insignificant compared to adaptive changes in the DNA code (all lifeforms considered). It's probably due to the fact the genomes (just DNA) have been evolving much longer than epigenomes (DNA + the molecules that attach to it + enzymes that catalyze this). Maybe over time, this system will be further tuned by evolution to allow robust adaptive responses in offspring in response to environmental stresses experienced by the parents.

I think Biowizard’s answer was extremely well-balanced and ‘spot on’.

Perhaps a single word/term could be amended in the above, if Biowizard permits – “are almost insignificant compared to adaptive changes in the DNA code (all lifeforms considered).” Maybe a better phrase here would have been ‘mutationally adaptive’. The medical literature is full of deficiency diseases due to mutationally faulty genes.

I would just like to amplify slightly.

If, flatearthsurvivor, you are referring to environment in general in the title to this thread, then I’m fairly sure we would have noticed clusters of people emerging from many of the different parts of the world with a noticeable propensity to excel, or fail, at a miscellany of endeavours in areas previously alien to them.
Has anyone ever noticed such a phenomenon?. I would love to hear from any of our members who know of such examples.

I’m excluding physiological adaptation such as when endurance athletes reared in higher altitude climates excel in performances at sea level. Or, for example, the fact that no eskimos appear to be lean in build; subcutaneous fat deposits help survival physiologically in cold climates. Or physiological adaptations such as those of the Terra Del Fuego Indigenes who appear to have a tolerance to cold – but it was Darwin (I think) who noted that they culturally dunked all newborn babies into ice cold water to test for survival capacity in their climate.


If you are referring to acquired characters, any such changes would have to be limited to those changes we all acquire before our breeding ages – which is a limited part of our lives. Our acquired knowledge, for example, and common sense seem to develop as we age. We seem to live mostly according to our primitive drives before we breed. So, from that aspect alone, our chances of transmitting useful acquired characters remains on a ‘reduced probability’ list.

Just some extra thoughts, flatearthsurvivor – but I liked Biowizard’s post.

[vivian maxine]

Tortoiseshell cats - that's an epigenetic effect, isn't it? Every torty I've known or heard about from a torty owner, has had personality problems (i.e. cranky and/or skittish). Same goes for calico.

Hmmmm? You, Biv, has just solved my mystery. I had a calico cat who was schizophrenic. No, I'm not giving her the title. She was diagnosed by the veterinarian as schizophrenic. He wanted to put her down but I said no. She lived her life her way for 18 years and she really was a maladjusted cat. Thank you for the answer.

[vivian maxine]

I know the OP already knows about this but I felt it an interesting enough article to post for anyone who hasn't seen it. I was fascinated by some of the possibilities of inheritance - even back beyond the parents - that the article mentions.

https://www.sciencedaily.com/releases/2 ... 133534.htm

[littletrio]

Doogles, for "DNA to be covalently modified" information must be communicated to promote the reception at the gates of the cell membrane, e.g., once the information is allowed to penetrate the cell body and integrate with the DNA the epigenetic modification process could begin. So, logically speaking, there must be a resonance or autonomous means for this adaption (survival of the species) process in connection with our central nervous system, environment, cognitive abilities, as well as, our level of consciousness awareness; thus........autopoiesis, provides a more accurate depiction.

[Eclogite]

I know this is heretical to some, but I can't help but wonder if the discounted theory that NOTHING can be inherited by offspring because of environmental factors encountered or endured by their parents.

I simply have my doubts as to its accuracy.

In one sense your doubts are, if not well founded, at least wholly understandable. Darwin himself, having no mechanism for the origin of variations upon which natural selection worked, did - at times - envisage a Lamarkian type inheritance. This shows up in differences in his discussion of that in various editions of On the Origin of Species. Rediscovery of the work of Mendel and then the development of the Modern Synthesis, removed the justification for these doubts.

Braininvat has concisely explained how that total rejection of Lamarkian inheritance has undergone a minor modification with the emergence of epigenetics. The two stumbling blocks for anyone pursuing a more full blooded Lamrkian evolutionary theory are:
1) The absence of a mechanism.
2) The absence of any solid (or even ephemeral) evidence.

The sense data/hormones taken in (as a register of environment) will transcend into inherent adaptive (blueprint/dna). But, this will only effect the potential offspring and must be passed down.

The phrase "will transcend into inherent adaptive" smacks of word salad.
1. What do you mean by "will transcend"? (That sounds very much like hippy science. I'd like you to help remove my nervousness on those grounds by trying for a more scientific term.)
2. Are you trying to say that specific genes will be altered by the response of the cell as it "registers its environment".

He has a heart of gold and is a freaking genius......check out a few youtube videos of his work.

n general YouTube videos are not a sound resource for studying science - although there are many honourable exceptions. I haven't studied Lipton's work in detail. His hypotheses may well be correct.** However, he is so far out on a branch compared with the rest of the biology community that he is on a different tree, if not a different forest. I suggest that making a judgement as to the value of his works from viewing videos is akin to assessing the safety of smoking by viewing tobacco advertisements.

[quote"littletrio"]Rupert Sheldrake, has been working on Morphogenetic Resonance for decades, too. Great stuff, i.e., the resonance of the herd actually helping develop the embryo[/quote]Sheldrake's work has been pretty well universally rejected and for good reason. If we are attracted to novelty in theories - and who isn't - and like dogma challenging initiatives (which I love) then Sheldrake delivers an initial smack in the face. Closer examination reveals that the smack has been delivered with a dead mackerel. In short, Sheldrake is proposing and promoting pseudoscience.

**Intellectually I am required to and therefore do keep an open mind even though the little I have read of his work offers me no real encouragement to suspect that he may be onto something. On an emotional level I have little doubt that the guy is seriously deluded.

[Braininvat]

Vivian, I don't know how the epigenetic influences on feline coat patterns would actually affect personality, so my remarks about torties and calicos should be taken as anecdotal - stories from owners and my own encounters. But there does seem to be a widespread belief that those cats tend to be nutty in some way. I will dig into the lit and see if I can find anything. Been meaning to do that for a while, so am glad you reminded me. My wife used to have a tortie who liked to be compressed under a bed pillow. I'm talking mashed flat. Reminded me of famed autism spokesperson Temple Grandin and her squeeze device she used in her youth to ease anxiety.

[vivian maxine]

Truly, Braininvat, I don't think your idea is far from the mark. We even see it in humans where hair color, body size, and such are claimed to influence the behavior of people True or not, we don't know but we get these sayings about red heads, green-eyed people, etc. I wonder if anything will ever be proven.

Hiding under a pillow. When I had my calico cat, if company came, she would find the tightes, darkest hidey-holes she could and she'd stay there until they left, if it was hours. Remember the old apartment-sized gas stoves that had about a six-inch space underneath? She once spent 8 hours there while the painter painted the apartment. She treid to climb doors and, if I boosted her at her back-side, she made it to the top and sat there waiting to be rescued.

Ah! Too much reminiscing.

[Eclogite]

Ah! Too much reminiscing.

Reminiscing isn't as good as it used to be.

[vivian maxine]

Ah! Too much reminiscing.

Reminiscing isn't as good as it used to be.

Not when time is short and dust is getting thicker.