Her’s an interesting piece of reading for the day. The capabilities of animals never ceases to amaze me!
I’ve recently come across a number of articles on the subject of epigenetics. According to LiveScience, epigenetics ‘literally means “above” or “on top of” genetics. It refers to external modifications to DNA that turn genes “on” or “off.” These modifications do not change the DNA sequence, but instead, they affect how cells “read” genes.‘
Studies have seemed to show that the effects of things like stress, obesity, and living through famine or war can be passed on from parents to children, and perhaps even to grandchildren and beyond. The effects of these experiences on a parent can alter the way genes are turned on or off in the DNA of one’s offspring. So, in my lay person understanding, it seems that parents might not just pass on their basic genetic material to their children, but also residual effects of certain life experiences.
I’m not going to pretend to understand it all, and I’m certainly not going to try and explain what I’ve read. It’s a bit too complex for me, and I think I’ll need to give these articles a few more readings to better get my head around the information. But this certainly adds a whole new layer to the way we think about genetic inheritance and the effects parents have on their children and future descendent. Our experiences, life style choices, and physical and mental health may be even more important to those who come after us than we previously thought.
If you’d like to read more, here are a few recent articles on epigenetics:
Confession: I have a tendency to think there is ‘One Right Answer’ to life’s big questions, and surprisingly enough (!), I often feel like I have that answer. However, I also know that it is utterly preposterous to think I actually have the answers to everything. On the contrary, I only know a tiny smidgen of all that’s to be known and understood in the universe, and things in life are rarely black-and-white. So, my ‘know-it-all’ self and my ‘I-don’t-know-jack-crap’ self are in constant battle. Sometimes it’s a bit exhausting to be arguing with one’s self all the time, but then again, it keeps me from getting bored!
So, that’s confession time out of the way. Now on to the more interesting stuff.
Recently I came across an amazing article about the evolution of adult milk drinking. Yeah, doesn’t sound that amazing probably, but trust me, it is. In a nutshell, for most of human history (or perhaps I should say pre-history) adults of our species could not really digest dairy, but somewhere around modern-day Hungary, perhaps about 11,000 years ago, there was a genetic mutation that kept that childhood milk-digesting ability working into adulthood, and that mutation was so advantageous for those who inherited it, that it spread like wildfire!
Still, about two-thirds of people currently living on the planet don’t handle milk so well… as in, drinking milk causes diarrhea and unpleasantness like that. However, the other one-third (roughly) can digest milk and it provides a valuable source of energy and nutrition. In some places, particularly in northern Europe, the percentage of adults who can digest dairy is up to around 99%! So, that’s a very brief run-down of the idea, but I highly suggest you check out this great article that explains it much better than I just did: Archaeology:The Milk Revolution (from nature.com).