Temporal Clustering in Multi-Generational Genealogical Data: Pre-Registered Analysis of 85 Family Lineages

We present pre-registered empirical analysis of temporal patterns across 85 verified genealogical families spanning 150 + years of birth records. This study was pre-registered on the Open Science Framework (https://osf.io/7njxr) on February 19, 2026, with hypotheses and methodology locked prior to data analysis completion. Statistical analysis reveals three empirical regularities in transgenerational temporal relationships, with a primary finding of significant clustering around 60-year combined maternal age windows (27.1% observed vs 7.0% expected by chance, p < 0.001, Cohen’s h = 0.58). Cross-validation across three independent data splits confirms pattern consistency (25.0–28.6% clustering). Stratified analysis demonstrates pattern universality across gender (male 28.6%, female 25.0%) and reveals significant historical period effects (1850–1899: 42.1% vs pre-1850: 24.2% clustering). These findings represent genuine empirical discovery protected against post-hoc hypothesis generation through pre-registration methodology.