What is qpAdm? Admixture modeling with f4-statistics, explained
qpAdm tests whether a population is a mixture of chosen sources and estimates the proportions. How it works, what it needs, and where it fails.
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Population genetics, explained
Plain-language guides to population genetics and ancient DNA: what qpAdm, f-statistics, D-statistics, qpWave, qpGraph, FST, PCA and DATES measure, how to read their results, and the data behind them.
Methods
How to read qpAdm results: p-values, weights and standard errors
What a qpAdm p-value, weights and standard errors mean, when a model is feasible, and the checks that separate a good model from a lucky fit.
Choosing right populations (outgroups) for qpAdm
Right populations decide what qpAdm can see. How to choose them, why the base matters, a starting panel, and the mistakes that cause false fits.
f-statistics explained: f2, f3, outgroup f3 and f4
f-statistics measure shared genetic drift. What f2, f3, outgroup f3 and f4 compute, how to read their sign and Z-score, and what each one tests.
D-statistics and the ABBA-BABA test, explained
The D-statistic, or ABBA-BABA test, detects gene flow from site patterns in four populations. How it works, how to read it, and its limits.
What is qpWave? Counting streams of ancestry
qpWave counts the streams of ancestry that link populations to a set of references. How its rank test works and how to read rank 0 and rank 1.
qpGraph and admixture graphs, explained
An admixture graph is a population tree with mixture edges. How qpGraph fits one, how to read the worst Z-score, and why many graphs can fit.
What is FST? Measuring genetic distance between populations
FST is the share of genetic variation between populations. What FST values mean in humans, the Hudson estimator, and how FST differs from f2.
PCA in population genetics: smartpca and projecting ancient genomes
PCA places genomes on axes of genetic variation. How smartpca works, why ancient genomes are projected, and what a PCA position does not mean.
Dating admixture with DATES: when did two populations mix?
DATES estimates when two ancestries mixed, from how ancestry blocks shorten over generations. How it works, on one genome, and its limits.
G25 and nMonte vs qpAdm: what PCA coordinates can and cannot tell you
G25 coordinates and nMonte fits are fast but give no test of fit. How they differ from qpAdm, and how to use both to find and test models.
Data
The Allen Ancient DNA Resource (AADR): 1240K, Human Origins and sample labels
The AADR is the curated dataset of ancient and modern genomes behind most ancient DNA studies. Its 1240K and Human Origins releases and labels.
Compare your 23andMe, AncestryDNA or MyHeritage raw data with ancient DNA
Use your 23andMe, AncestryDNA or MyHeritage raw data with ancient genomes: the merge, what qpAdm, f4 and PCA can say about one genome, and limits.
Ancestry
Hunter-gatherer, farmer and steppe ancestry: the three-way model of Europeans
Most Europeans descend from hunter-gatherers, Anatolian farmers and Yamnaya-related steppe herders. Who they were, and how to model them.