By now I think that you might agree that we are not looking at an evolutionary advancement (magic bullet) so much as an environmental one. Keep in mind that we are talking about an anatomically modern human population. I’ve never thought much of the Aquatic Ape theory… seemed a little far-fetched… but what do I know?

Yes, iodine is available all over the world and, from what I have read, tends to decrease as you go up in altitude from sea level. It resides in the soil and enters the food chain in the normal ways. The supplies can be inconsistent from place to place: being almost nonexistent in some places while in near by areas it can be more than sufficient for positive human development.

One study I read (conducted in an iodine deficient area in China in the 90’s) showed results that would indicate that a fetus requires iodine as early as possible for optimum development. Once it is acquired in the necessary amount (very small) it does not seem to have any additional developmental advantage. This study identified results up to as much as a 10% IQ advantage over the subjects that did not receive it during incubation at all. This study group also had physiological problems that limited their quality of life. Subjects who received iodine in the 2nd or 3rd trimesters also had an IQ defecate (3 to 7%) when compared to those who received it during the 1st trimester.

I don’t know but it would seem that for optimum effect you need a consistent source at or above the minimum requirement, for a period of 3 or 4 generations to begin see the kind of advancements, and sudden population growth, that genetic migration trackers say they see. The sea seems to be the ideal, iodine rich, environment for this to take place.

FYI the two links did not work

+ here’s a couple of articles on iodine and evolution. Cunnane seems to be the only person who has published on thinks like this before.

http://iodine4health.com/special/evolution/cunnane_evolution.htm

http://iodine4health.com/special/evolution/venturi_evolution.htm

Your idea reminds me a lot of the Aquatic Ape Hypothesis, a deeply unfashionable anthropological theory that is making a bit of a comeback at the moment. It argued that the common ancestor of the hominids went through an aquatic wading stage which gave birth to many of our modern features, walking upright, hairless bodies and crucially, the access to the oily fish allowed the brain to develop.
Although, in relation to this post, I guess we are talking about a slow iterated process rather than a sudden evolutionary magic bullet (and evolution doesn’t do ‘magic bullets’). I does seem possible that access to iodine could have been a crucial factor in the development of language over an evolutionary timescale. I’ll mention this to Dan Deidu when I next see him.

A few years ago while working with my local Kiwanis Club I learned about the positive and negative effects of iodine on humans through their project to provide iodine salt plants around the world to help children.

Later I was reading about genetic migration pattern research and it was mentioned that about 60,000 years ago humans began spreading along the coasts of the world from sub-Saharan Africa. It was theorized that early populations of modern humans were forced to move from the interior to the coasts, probably due of climate change. It was also theorized that there some kind of epiphany was experienced (Language development was mentioned as one of the possibilities) prior to or during the early stages of the spread of populations out of the African Continent.

My conjecture draws on the fact that (1) iodine is important to individual human language development (2) iodine is most plentiful in the oceans and as a result in the flora and fauna that is supported by the oceans (3) the timing of events related to genetic migration evidence i.e. relative dates between 60,000 and 80,000 years ago (4) and the supposed development of language around the time of the increase of population leading to the spread of these people along the coasts of the Earth.

Is it possible early humans that moved from the interior of Africa to the coastal areas encountered an environment which included foods which contained levels of iodine? Studies have shown that iodine, obtained in early childhood can increase human IQ by 3 to 5%.

A reliable iodine supply, over a number of generations, could have been enough to enable a population to be more successful in a number of ways including language development followed by human population migration up the East cost of sub-Saharan Africa and out the rest of the Earth.