andres@ut-sally.UUCP (01/01/70)
In article <1598@rayssd.RAY.COM> m1b@rayssd.RAY.COM (M. Joseph Barone) writes: >Now, to refute the premise that the average lifespan >during the Middle Ages was 30, people are exempting just about every >condition that brought that average down! So I suppose that if you >discount infant mortality, wars, pestilence, famine, and plagues, then >the average lifespan is indeed much higher! Somehow, though, I don't >think this is sound statistical analysis. We're getting into a matter of definitions here - what is "life span" vs. "life expectancy"? Let's put it this way - if half the people die by age 5 (which they did, and still do in much of the world), but the "average life span" is 30-35, most of the rest must last a while. My own understanding of the meaning of "life span" is something like the biblical three score and ten- how long can a person with the luck to survive these scourges expect to live.
ekwok@cadev4.intel.com (Edward C. Kwok) (09/23/87)
I am told that dinosaurs became extinct within a very short period of time, leading scientists to believe that some catastrophic event caused the extinction (e.g. large meteorite struck the earth etc.) Does anyone know of any theory being proposed that blamed a virus for their extinction? I can imagine a virus attacking a particular nucleic acid sequence found only in dinosaurs, leading to inability to produce, say dinosaur growth hormone or any other essential protein. Or plainly causing dinosaur acquired immune deficiency syndrome. I am afraid the human species may be facing the same problem.
acphssrw@csun.UUCP (09/24/87)
In article <1057@mipos3.intel.com> ekwok@cadev4.UUCP (Edward C. Kwok) writes: >Does anyone know of any theory being proposed that blamed a virus for >[the dinosaurs'] extinction? The difficulty with the Cretaceous extinctions has always been explaining the demise of half the species on the Earth at the time, including plants, phytoplankton, fishes, etc. etc. Getting rid of just the dinosaurs is (relatively) easy. The impact theory has the merit of explaining all of these extinctions with a single event we know for a fact can happen. I think we know for a fact it did happen; Luis Alvarez has an article on the current status of the impact theory in the July _Physics Today_. Must reading, and accessible to lay persons. Steve Walton, Cal State Northridge
turpin@ut-sally.UUCP (09/25/87)
In article <1057@mipos3.intel.com>, ekwok@cadev4.intel.com (Edward C. Kwok) writes: > Does anyone > know of any theory being proposed that blamed a virus for their extinction? > I can imagine a virus attacking a particular nucleic acid sequence found > only in dinosaurs, leading to inability to produce, say dinosaur growth > hormone or any other essential protein. Or plainly causing dinosaur > acquired immune deficiency syndrome. I am afraid the human species may > be facing the same problem. It may be possible for new viruses to wipe out species, and it is certainly the case that HIV is a major health problem reaching epidemic proportions. But if you are seriously concerned about the potential extinction of the human race, HIV is not a likely cause. For several centuries Europe lived with an epidemic disease that was incurable, had a high mortality rate, and was transmitted through bodily fluids by sex and birth. This disease was syphilis. While it killed many, it did not cause severe population decrease, in sharp contrast to the plague. Why? Two reaons. (1) Its mode of transmission is very restrictive. Like HIV, syphillis is hard to get. You have to have sexual intercourse with someone who has it, be born of an infected woman, or (in this age) share needles. (2) You can live a long time with it. Syphillis (and HIV) can take years to kill. If you get it when you are twenty by the most likely means, you will likely live to see twenty-five or thirty, maybe not even showing symptoms then. While this seems short today, in times past this was almost a normal life span. AIDS is a terrible disease that is taking many victims, and I hope that a cure or effective vaccine is developed soon. If it was more contagious, like the flu, concern about human extinction would be warranted. Fortunately, it isn't. Russell
dgary@ecsvax.UUCP (D Gary Grady) (09/25/87)
In article <9114@ut-sally.UUCP> turpin@ut-sally.UUCP (Russell Turpin) writes: >. . . (2) You can live a long >time with it. Syphillis (and HIV) can take years to kill. If you >get it when you are twenty by the most likely means, you will >likely live to see twenty-five or thirty, maybe not even showing >symptoms then. While this seems short today, in times past this >was almost a normal life span. In the midst of an otherwise excellent posting, Russell repeats a common misconception: that in years gone by, 30 was a "normal" life span. The confusion arises because in years past the life expectancy at birth was about 30 to 35. This was NOT because people tended to live to be that age, however, but because infant mortality was so high, pulling the mean down. Anyone who survived childhood had an excellent chance of reaching 70 or more. A glance at the life spans of historical personages shows the "normal" life span of an adult to have been very little different from what we see today, at least among the upper classes able to live in decent dwellings and eat adequate food. -- D Gary Grady (919) 286-4296 USENET: {seismo,decvax,ihnp4,akgua,etc.}!mcnc!ecsvax!dgary BITNET: dgary@ecsvax.bitnet
urban@sol.SPS.TRW.COM (Michael Urban) (09/25/87)
In article <1057@mipos3.intel.com> ekwok@cadev4.UUCP (Edward C. Kwok) writes: > >I am told that dinosaurs became extinct within a very short period of >time, leading scientists to believe that some catastrophic event caused >the extinction (e.g. large meteorite struck the earth etc.) Does anyone >know of any theory being proposed that blamed a virus for their extinction? >I can imagine a virus attacking a particular nucleic acid sequence found >only in dinosaurs, leading to inability to produce, say dinosaur growth >hormone or any other essential protein. Or plainly causing dinosaur >acquired immune deficiency syndrome. I am afraid the human species may >be facing the same problem. The idea of an epidemic being the cause of the extinction of the dinosaurs seems a bit suspect, since ALL of the very diverse species of dinosaurs, but not the smaller reptiles, were wiped out at approximately the same time. It's very easy to think of "the dinosaurs" as one big homogenous species of critter, but of course they were undoubtedly as genetically assorted as the mammals are today (with, I assume, interesting variations according to climate, vegetation, etc.) -- Mike Urban ...!trwrb!trwspp!spp2!urban "You're in a maze of twisty UUCP connections, all alike"
beede@hubcap.UUCP (Mike Beede) (09/26/87)
in article <3913@ecsvax.UUCP>, dgary@ecsvax.UUCP (D Gary Grady) says: > > > 70 or more. A glance at the life spans of historical personages shows > the "normal" life span of an adult to have been very little different > from what we see today, at least among the upper classes able to live in > decent dwellings and eat adequate food. As Marshal McCloud would say, ``there yuh go.'' The people you refer to were a small minority, as I understand it. I don't think the previous poster meant that given proper nutrition, people lived substanially shorter lives, just that on the average adults died earlier (from whatever environmental causes you care to specify). -- Mike Beede Computer Science Dept. UUCP: . . . !hubcap!beede Clemson University INET: beede@hubcap.clemson.edu Clemson SC 29634-1906 YOUR DIME: (803)656-{2845,3444}
msb@sq.UUCP (09/28/87)
> > ... While [25-30] seems short today, in times past this > > was almost a normal life span. > In the midst of an otherwise excellent posting, Russell repeats a common > misconception: that in years gone by, 30 was a "normal" life span. ... > ... A glance at the life spans of historical personages shows > the "normal" life span of an adult to have been very little different > from what we see today, at least among the upper classes able to live in > decent dwellings and eat adequate food. But it isn't the upper classes who are under discussion, it's the "normal" people. Gary, do you have information on the lifespans of those you *haven't* heard of? I don't, but I think that age 70 was pretty rare. Mark Brader
andres@ut-sally.UUCP (Bennett Andres) (09/28/87)
In article <1987Sep27.223915.8232@sq.uucp> msb@sq.UUCP (Mark Brader) writes: > >But it isn't the upper classes who are under discussion, it's the "normal" >people. Gary, do you have information on the lifespans of those you *haven't* >heard of? I don't, but I think that age 70 was pretty rare. It isn't just the upper classes on whom there exists data. Parish priests kept detailed records of births and deaths throughout Europe. In fact, if a person survived childhood, wars, and the grimly regular famines, he stood an excellent chance of reaching, if not 70, at least 60. The masculine pronoun is intentional - childbirth was a major killer also. Of all these, the rich were exempt only from famine. People today don't know what a real epidemic is. As recently as 1918-19, a flu epidemic killed an estimated 20 million worldwide. It did so by weakening its victims so that they were susceptible to massive bacterial infection. Sound familiar?
m1b@rayssd.UUCP (09/29/87)
The first divergence from the original discussion concerned
syphilis being a wimpy epidemic during the Middle Ages because it took
so long to kill its victims. The article stated that since the average
lifespan during the Middle Ages was around 30, people normally died from
something else. Now, to refute the premise that the average lifespan
during the Middle Ages was 30, people are exempting just about every
condition that brought that average down! So I suppose that if you
discount infant mortality, wars, pestilence, famine, and plagues, then
the average lifespan is indeed much higher! Somehow, though, I don't
think this is sound statistical analysis.
Joe Barone ---------------------------> m1b@rayssd.RAY.COM
{cbosgd, gatech, ihnp4, linus, mirror, uiucdcs}!rayssd!m1b
Heroes have an infinite capacity for stupidity. Thus are legends born!jnp@calmasd.GE.COM (John Pantone) (10/01/87)
(M. Joseph Barone) writes: > ....... > Now, to refute the premise that the average lifespan > during the Middle Ages was 30, people are exempting just about every > condition that brought that average down! > ....... > Somehow, though, I don't think this is sound statistical analysis. Right Joe. In fact it isn't even good english. There is a difference between the average lifeSPAN and life expectancy. The fact is that the lifespan of humans hasn't really changed all that much over many hundreds, maybe even thousands, of years. What HAS changed dramatically is the life expectancy (number of years you can expect to live). This has gone up, fairly continuously, for the same hundreds/thousands of years. (I think that there have been some very small, local, dips within my lifetime - but the trend is overwhelmingly upward). The point is that although people have always been ABLE to live to 80 they haven't done so, very often, until relatively recent times. Read some on the Middle Ages - it was a brutal, disease ridden time. The chances were overwhelmingly good that you would only live to see your thirties. -- These opinions are solely mine and in no way reflect those of my employer. John M. Pantone @ GE/Calma R&D, Data Management Group, San Diego ...{ucbvax|decvax}!sdcsvax!calmasd!jnp jnp@calmasd.GE.COM