Inferring the demographic histories of populations has wide applications in population, ecological, and conservation genomics. We present Stairway Plot 2, a cross-platform program package for this task using SNP frequency spectra. It is based on a nonparametric method with the capability of handling folded SNP frequency spectra (that is, when the ancestral alleles of the SNPs are unknown) of thousands of samples produced with genotyping-by-sequencing technologies; therefore, it is particularly suitable for nonmodel organisms.

中文翻译：

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阶梯图 2：人口统计历史推断与折叠 SNP 频谱

推断种群的人口历史在种群、生态和保护基因组学中有广泛的应用。我们展示了楼梯图 2，这是一个使用 SNP 频谱的任务的跨平台程序包。它基于一种非参数方法，能够处理通过基因分型测序技术产生的数千个样本的折叠 SNP 频谱（即，当 SNP 的祖先等位基因未知时）；因此，它特别适用于非模式生物。