This is a post about me not being able to get my head around the necessary math, and I'd love some help from whoever is more capable than I.
Let's postulate a small Celenian town, called East-of-Evening, wherein live 1500 faeries (the blonde, violet-eyed grey elves).
Let's assume the 1e AD&D DMG has the most Greyhawkian data on olven lifespan, and let's assume the average faerie lives 1500 years (the minimum on the Venerable age category, which itself is the average roll on the Maximum Character Age Table) before dying (or passing eastward to some mysterious isle for the more Tolkeinesque or 2e of you).
Let's assume faerie population remains steady over time.
Question: How often is a faerie born in East-of-Evening?
If 1500 are born every 1500 years, that's an average of 1 per year, right? Then you have to account for those who die of disease, violence, childbirth, hippogriff accidents, potion immiscibility, and so on, so maybe 2 a year.
One way of looking at it is that the average lifespan in the Player's Handbook is the average time a faerie elf lives before succumbing to old age, which isn't really the same as the average lifespan, since lots of things can kill an elf before old age does. So if you wanted to be rigorous about it you could figure out leading causes of death at various ages and calculate the actual average lifespan from that, but I'd probably just give everyone a spare as a simplification.
So, if we don't worry about mortality from non-aging causes, I think what you're saying is this:
1) we assume our faerie town of 1500 has 1 faerie of each age from 1 to 1500
2) every year someone dies
3) every year someone is born
4) population remains stable
Is that right?
I was just speaking in terms of averages. If 1500 elves, on average, completely replace their population every 1500 years, then on average that's one birth a year. Some years there'd be no births, and other years there'd be several.
The Life expectancy article on Wikipedia says that during the middle ages, the average life expectancy was 30-35 years, but those who survived past 40 had a good chance of living another 15-20 years. With elves, the possibility of living to be 2000 is going to really throw off that average, but the things that killed humans before they turned 40 could also kill elves. Perhaps not childbirth, if elves don't typically mate when they're that young, but Oerth is a dangerous place. How many random monster attacks is a village in the Gnarley going to see in a year? How many of those will result in fatalities among those defending the village? My point is, elves are likely going to have to reproduce more quickly than one birth per 1500 people per year if they're going to avoid dying out.
Also: how much of the elven reproductive rate is due to low fertility and how much due to other factors (increased likelihood of dying in childbirth, increased number of stillbirths, increased infant deaths)?
Adding to Rasgon's point about elves dying due to violence, disease, etc., you could simply determine how many elves die from such things yearly, on average, and add that number to the successful births per year.
For example, if you decide that of the 1500 elves in a community 2 die from disease, 3 from accidents, 1 from childbirth, and 20 from war with various enemies, you simply add 26 to the original 1 for a total of 27 births per year, on average, in an elven community of 1500 individuals. This may be assumed an average for the World of Greyhawk.
If the community is in a more dangerous locale, the total deaths per year may be higher, which would indicate that the population is dwindling, unless the community takes specific measures to replace their dying members. If the community is in a safer locale, it may be increasing in population, or not, if you consider that affluence tends to lower the number of children couples have.
I was imagining East-of-Evening in the heartlands of Celene i.e. very very safe and protected from foreign raids. And I'd also imagine that Celene (along with maybe the interior of Veluna and possibly Keoland) has to be one of the safest places to live in the entire Flanaess. (Unless you go back to Vecna times, what war besides the Hateful Wars ever even touched the heartland of Celene?)
But I like SirXaris' estimates as a baseline for most of the Flanaess.
What started this whole line of thought was wondering how common births would be to the citizens of East-of-Evening: Would they be rare enough that every olven birth demands a community-wide celebration? Or would it be closer to human norms, where birth celebrations occur on the family and personal level, but are only occasions for civic celebration for important lineages.
If we exclude the 20 dead in wars (though maybe 2 die/year off adventuring somewhere else?) then maybe we have about 7 births/year in East-of-Evening, which still seems closer to a community-wide celebration for each one than private familial observance.
Demographics also need to account for immigration in and out of the community. If it's very safe, then more faeries may go there. It would be offset by residents leaving for other towns or other reasons (like youngsters becoming adventurers).
From Dragon Magazine #76, the Sage Advice column also pegs elven pregnancy at possibly as long as 2 years (page 64).
You should also consider issues of maternal morbidity and mortality, and infant mortality.
Grey and high elves should be presumed to have high quality health care, leading to good outcomes from pregnancy and childbirth. Wood elves could theoretically have higher risks.
Then there's the issue of fertility. How fertile are elven women, and how often are they likely to conceive? How does culture impact childbearing?
Those issues will help guide population growth. For example, IMC, elven women are only capable of reproduction every seven years ... think pon farr. Narrow windows, wide spread. If pregnancy occurs and is successful, an elven woman can through her life span have a large family but the siblings might be decades or even centuries apart in age. Barring disease, war or misfortune, the population would slowly grow.
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum
Canonfire! is a production of the Thursday Group in assocation with GREYtalk and Canonfire! Enterprises