As we all are aware of recent researches that demonstrate the slow-changeability and the flexibility of gens, by the variables of climate, nutrition, and stress, through the number of generations (it varies). As a result, being more specific in this perspective could be more helpful, on the avenue of choosing variables.

Thank you for your interest Mrs. Benz.

I am actually interested in estimating a census population size (sadly, not "effective population size") of an relatively stable settlement. By "stable" I mean minimum migration in and out no dramatic change caused by earthquake, volcanic activity or disease. I'm aware this definition of stability looks like "let's assume chicken as a sphere" but maybe I should start from this point.

Thank you for your interest Dr. Lehmann.

I don't have a particular settlement actually. My research group is interested in Neolithic period mainly, with some side projects from Bronze and Iron Age, for human and animal samples. To answer your question, I may say Anatolian Neolithic settlements, for example Çatalhöyük.

I'm fully aware that these settlements (and Anatolia, in general) have dynamic histories as people migrate to and from, and this complicates census estimations. I read some papers written by archeologists that infers population amounts by determining floor areas of houses and natural resources nearby but I was curious maybe we can estimate population size by inspecting genetic variation among human remains that dated close to each other. I'm stuck right now, maybe sticking the old way useful at this point.

I'm not sure genetics will be a useful way to estimate population size, with one exception: possible sex. I'm going to be speaking mostly about ancient DNA because you mentioned Neolithic remains.

Especially in regards to ancient DNA, the first problem would be cost to do it on an entire population, as its very expensive (at least here in the US). You also have to contend with accuracy and reliability as an issue. Degradation rates are still being researched for accuracy, but seem to be as variable as taphonomic rates (to me, at least), which means you never know how much is left or its preserved condition (not to mention the high rate of modern contamination, which is a whole other discussion).

On top of that, defining what genetically constituted a population, given heavy degradation, would be paramount and difficult. You would have to be very specific on what would constitute inclusion versus exclusion from a population using potentially just a small portion of the genome, and have some excellent reasoning and research to back it up.

With sex, they have found success using STRs (short tandem repeats), but these also depend on not being too heavily degraded. So if you have a well preserved sample with some unknown perfect recipe for excellent DNA preservation and unlimited budget, you could potentially sex them. But I can't think of a way, given current understanding and technology, that we can determine inclusion vs. exclusion, or even contemporaneous existence, with any accuracy and reliability using ancient DNA.

I am a specialist in this subject. Apart from some general reading regarding this subject I am afraid that I cannot help. However, I think that genetics could not give any help in order to estimate the size of the population of an abandoned settlement.@

Genetic approaches to estimating population size in ancient settlements involve analyzing DNA from ancient human remains. Here's how it works:

1. Genetic Diversity: The level of genetic diversity within a population can provide clues about its size. Larger populations tend to have higher genetic diversity due to a larger number of individuals contributing to the gene pool over time. Conversely, smaller populations may exhibit lower genetic diversity due to genetic drift and founder effects.

2. Effective Population Size (Ne) This is a concept from population genetics that refers to the size of an idealized population that would experience the same amount of genetic drift or loss of genetic variation as the actual population under consideration. By estimating Ne from genetic data, researchers can infer the historical population size of a group.

3. **Coalescent Theory**: Coalescent theory is used to model the process of genetic lineages coalescing backward in time to a common ancestor. By applying this theory to genetic data from ancient individuals, researchers can estimate past population sizes and demographic events such as population expansions or contractions.

4. Ancient DNA (aDNA) Analysis. Advances in sequencing technology have enabled the extraction and analysis of DNA from ancient human remains. By sequencing genomes from multiple individuals within a population, researchers can infer aspects of population size, structure, and history.

5. Comparison with Modern Populations: Genetic data from ancient populations can be compared with modern populations to estimate changes in population size over time. This comparison can reveal patterns of population growth, decline, migration, and admixture.

6. Integration with Archaeological and Historical Data: Genetic estimates of population size should be interpreted in conjunction with other lines of evidence, such as archaeological findings, historical records, and paleoenvironmental data. This multidisciplinary approach helps to refine population estimates and reconstruct the dynamics of ancient societies more accurately.

Overall, genetic approaches provide valuable insights into the population dynamics of ancient settlements, but they are most effective when combined with other sources of evidence to build a comprehensive understanding of past human populations.