Inherited traits are physical things, not some supernatural "spirit" that is in a person. A cat is tame because of different brain structure or hormone levels - physical traits passed down in DNA. Change a person's hormones, and their personalty changes. There's no mystery here people.
Humans seems to have a common aversion to snakes and spiders- is that inborn- is it part of our dna? Studies are looking at that possibility. http://www.sciencedaily.com/releases/2008/02/080227121840.html Collective memory is not too hard to believe in.
Lets look at the mother. The egg cells are created along with the baby and are not being produced all the time like the sperms cells. So their nucleus and DNA is in that sence static.
So in order for the mother to pass on a memory (tragic or otherwise) through the DNA what would need to happend was:
* The mother experience the event and record in her brain.
* The memory is somehow selected. then it is somehow transcribed by an uknown mechanism into an unknown thing where it is stored in some unknown format. Keep in mind the memories seem to be stored as a pattern of synapses among millions of neurons.
* Those things from before travel to all the moms egg-cells and go into the cells. Here they begin to manipulate the DNA and splice the information into them. That information need to be stored in such a way that if affect the way the brain grow so that the moms memories are inserted.
Furthermore, notice that, just like the fingerprints and all other structures in humans, the exact layout of the brain is not known. How does the DNA know exactly how to affect the neural layout of the brain so that the memory is interserted?
Its a cute idea, but a-priori i think it has a lot of things talking against it, particulary the transcription/encoding phase. I think the greatest problem is the distributed layout of the brain; if the brain work any way like a normal hopfield network, no two memories are stored a like in different brains, but will depend on the topology of the other brain which is determined by what other memories the baby will learn sometimes in the future. Thats a pretty big problem.
That, and the fact there are no reliable observations of this happening, is why i think it is unlikely.
wobble - Evolution work at a much slower pace. Very simplified:
The DNA is a kind of blueprint that lies inside each egg-cell and sperm-cell. When those are mixed in the baby factory, out comes a baby which is a mix of these two blueprints. The mixed blueprint is also stored in the baby and the process continue. So the blueprints are not affected by how the mom and dad live - they are static, and will only change because of:
a) The mixing-part.
b) errors, coffee-stains and so on will sometimes cause the blueprint to change in a small way. Most changes are bad, a few are God.
c) A few other things that are not so important for humans and this discussion.
Top 100 Stories of 2009 #61: Child Abuse Leaves Its Mark on Victim’s DNA
by Amy Barth
From the January-February special issue (Discover Magazine); published online December 28, 2009
The brains of people who were abused as children and then commit suicide show DNA modifications that made them particularly sensitive to stress.
Childhood trauma may leave a lasting imprint not just on the psyche but also in the DNA. This news comes from McGill University and the Suicide Brain Bank, a Quebec-based organization that carried out autopsies on suicide victims who had been abused as kids. Across the board, their brains showed DNA modifications that made them particularly sensitive to stress. Although gene variations are primarily inherited at conception, the findings show that environmental impacts can also introduce them later on. “The idea that abuse changes how genes function opens a new window for behavioral and drug therapy,” says study leader and neuroscientist Patrick McGowan.
During periods of adversity, the brain triggers release of cortisol, a hormone responsible for the fight-or-flight response. Due to differential gene expression associated with stress, the brains of child-abuse victims had lower levels of glucocorticoid receptors, McGowan found. Cortisol normally binds to these receptors; with fewer of them present, there is more cortisol and less resilience to feelings of stress.
In his study, McGowan reviewed medical records and police reports and interviewed family members to determine whether a subject was abused early in life. He then examined the subjects’ brain tissues and found that among those who had been abused, glucocorticoid-receptor expression was reduced by 40 percent. “If we can identify how these changes occur, we can identify those at high risk and ultimately find ways to treat them,” McGowan says.
wow! Thanks for all of these great replies. This whole subject has fascinated the fringes of my mind for a long time and reading all of your opinions and knowledge is interesting to say the least. What's intriguing to me is that we just don't know for sure to what extent DNA affects us at the molecular level and where the imprints begin and end. I still strongly believe that experiences - both positive and negative - imprint on us somehow to the extent that it can be transmitted to our progeny. A lot is made of negative impact, but what about positive? When you're in a place where you're truly happy, I mean deep down happy, can that not have an imprint so that your descendants somehow feel happy where you did? It sounds so ridiculous but at the same time it's an intriguing hypothesis - at least to me!!
Your DNA when you die isn't different from your DNA when you were born unless it is damaged (by a virus),
so no, there is no hidden data about your life accumulated in there for future generations to access.
I think you need to take into consideration that the DNA is not a perfect copying mechanism and that there are mathematical formulas that describe the rate of this DNA degradation and can use it to trace our migration out of Africa. ERV are one way there may be more.
Plus we need to consider egg cells and sperm cells do not carry exact copies of our DNA and are effected by Endogenous retroviruses ( http://en.wikipedia.org/wiki/Endogenous_retrovirus)
While we are able to read the entire human genome we do not know how everything works, and there are some very complicate processes that work in combinations with one another. So to state dogmatically : "no, there is no hidden data about your life accumulated in there for future generations to access." is to speak in ignorance and assumption, as if all these processes are thoroughly understood in all their complex interactions.
Scientists know how to decode the DNA, we can read it. All of it.
There is nothing in it other than instructions for how to build a body, and non-functional damage (lots of it).
Reading DNA with super computers is one thing. And understanding all the complex interactions that the DNA molecule makes happen when this DNA code is used to make a species is another completely different thing and can not be used to substantiate your first assumption that: "no, there is no hidden data about your life accumulated in there for future generations to access."
Apple and Oranges, or in other words not a fair comparison.
So the blueprints are not affected by how the mom and dad live,
Yes but we still have natural selection, and these determine what adaptive features of personality traits caused DNA mutation get passed on, I think we limit ourselves if we think of DNA mutations just causing bigger brains and missing tails and not including personality traits cause by a whole host of complexities not.
Here is an interesting piece on dna mutation rates:
Endogenous retroviruses (ERVs
Thanks so much for the links, frankiespeakin - I can't wrap my head around them right now (had a shitty day) but I'll definitely delve into them on the weekend.