Archaeologica.org

Interesting point there Min. If these people had no immunity to these diseases I wonder if that means they reached the Americas before the diseases arose, and if so, when did these diseases arise, might be an avenue worth exploring.

One theory I've seen holds that most of these diseases arose after the beginnings of agriculture and the domestication of livestock.

Of course, agriculture and domestication of animals occured among American Indians, too, so there must have been an additional dynamic.

Interesting Min, I think I'll see what I can find out cos if these are Old World diseases with a traceable time scale it could have some interesting results.
As I pointed out earlier, in the early part of the 19C as many as one third of our population had survived Smallpox which means a long time exposure to the disease, the question is how long?

http://www.who.int/mediacentre/factsheets/smallpox/

Says here that Smallpox is 3000 yrs old, if native Americans had no DEVELOPED immunity they must have reached the Americas prior to that.

For all the talk of bubonic plague and today aids, smallpox seems to be the killer of all millenia. It has been extremely virulent and it singlehandedly the greatest killer of indigenous peoples in the americas.

You might want to start here digit, and follow the primary sources in this article:
http://en.wikipedia.org/wiki/Smallpox


p.s. very interesting note in here of how the people of Indian began innoculating as early as 1000bce.

This is freaking me out.
Everyone is slightly ahead of my posts.

How is the age of a disease determined? is there genetic evidence of the age? if not and this is based only on historical records, then small pox and other old world disease would be much much older. (which I personally think). and a lack of immunity to old world disease's perhaps indicating an earlier occupation of the Americas would also apply to the occupation dates of the pacific Islands as well, right?

This freaking me out.
Everyone is slightly ahead of my posts.

Not to worry, FM ... you'll catch up!

Jared Diamond in Guns, Germs and Steel does a decent job of explaining why Native Americans were so susceptible to European diseases. Most of the big killers were developed on the Eurasian continent in isolation from the Americas as a result of the transmission of diseases from livestock to humans. Cowpox ==> Smallpox, etc. There were no suitable animals for livestock in the Americas and by the time Europeans showed up, a portion of the newcomers were already immune.

Ramesses V, d c 1140 BC is supposed to have smallpox lesions on his mummy.

Don't know RW but that is accademic to my point at this time. A disease does not of itself create immunity in a host, it simply works through natural selection to increase the percentage of immune individuals within a group. A virulent new disease can kill 90% of infected people if the remaining 10% have an existing immunity, if the disease then passes on and reappears 20 years later the death toll will drop because a larger percentage of the population are now immune due to the interbreeding of immune people. Over a period of time the population can then live with the disease.
This is supposed to be what happened with recurrent bouts of Plague, therefore if 90+% of peole die when exposed to a disease it infers that they have had no previous exposure.
Smallpox is supposed to be 3000 yrs old, that suggests that native Americans reached the Americas earlier than 3000 yrs ago. What I need to find now is if any of the other diseases, Measles for example, have been around for much longer.

Records for that may be lacking.

I don't think I agree with all of that Digit. Immunity is not directly inheretable as far as I know. You do have cases, where certain genetic defects can produce immunities. For example it is said, that sickle cell anemia may be the result of selection brought about by exposure to malaria, since sickle shaped red cells can not support the virus. However, this is one case where the cure may be worse than the disease.

The new field of epigenetics offers some interesting research on acquired heredity which is not passed through genes, but as far as I know, there has been no definitive talk of acquired immunity.

I think you have to make a distinction between genetic problems, bacterial diseases and viral diseases.

Smallpox is supposed to be 3000 yrs old, that suggests that native Americans reached the Americas earlier than 3000 yrs ago. What I need to find now is if any of the other diseases, Measles for example, have been around for much longer.

Digit, you're getting into a fascinating area of archaeogenetics that will provide answers for years to come. When a population suffers a pandemic, very often the disease leaves a genetic trace in the survivors' DNA and offspring. For example, by process of elimination you could theoretically determine when certain native populations isolated themselves in the Americas.