Ezra × Piper
All COI values calculated from full 9-generation pedigree. How to calculate COI
Pedigrees alone can be hard. This tool helps.
Highlight common ancestors, trace shared kennels, and see each ancestor's pedigree-predicted contribution to the cross. Without sequencing the dogs directly, this does not replace genetic analysis — it is a pedigree-based estimate, not a measure of actual shared DNA.
The 10-generation approach was inspired by the 2025 PNAS Special Feature on canine genetics—particularly the German Shepherd genomic time series showing how breeding decisions accumulate across decades. Scarsbrook et al., A 120-y time series of genomes reveals the consequences of closed breeding in German Shepherd Dogs, PNAS (2025)
Visual Pedigree Tree
The tree loads fit to your screen width. Ezra × Piper (the breeding pair) are on the left; scroll right for deeper generations. Gens 1–7 show full names; gens 8–9 show abbreviated names or colored bars. On a phone, pinch with two fingers to zoom; tap a dog to highlight every place it appears (the bar below shows which box you tapped). Use Fit all for a bird's-eye view.
← Scroll right for deeper generations · Scroll down for more dogs · Click any dog to lock highlights · Pinch with two fingers to zoom (phone/tablet) · Ctrl+scroll to zoom (desktop) →
Wright's COI Path Table
Top 20 contributing common ancestors from 123 total, spanning 618 individual cross-COI paths.
| Common Ancestor | n₁ (Ezra) | n₂ (Piper) | Contribution | Notes |
|---|---|---|---|---|
| CA BISS Am Ch Avanti's All For One Elan | 7 | 4–7 | 0.439% | 8 paths through both sides |
| CA Am Ch Saul's Tequila Mockingbird | 5 | 4 | 0.391% | |
| CA Am GCh Fendanesylcrests See You Later Allie-Gator | 5 | 4 | 0.391% | |
| CA BISS Am Ch Honey Lane's Highlight | 7–9 | 6–9 | 0.275% | Deep foundation dog, 120 cross paths |
| CA Am Ch Elan's Royhl Enchantment | 6–7 | 7 | 0.146% | 8 paths through both sides |
| CA Am Ch Don-Lu's Preferred Risk | 7–9 | 6–9 | 0.126% | Deep foundation dog, 40 cross paths |
| CA Am Ch Challenger's Allegra V Avanti | 7–9 | 6–9 | 0.126% | Deep foundation dog, 40 cross paths |
| CA Am Ch Krisda's Bastet | 6–9 | 8 | 0.110% | Deep foundation dog, 24 cross paths |
| CA Am Ch Helisain Monsieur | 8 | 5–8 | 0.110% | 8 paths through both sides |
| CA Am Ch Avanti's Taylor Dane | 8 | 5–8 | 0.110% | 8 paths through both sides |
| CA Am & Can Ch Moredanes Rack 'Em & Stack 'Em | 6 | 5 | 0.098% | |
| CA Am & Can Ch Lagarada Sahara La Bolero | 6 | 5 | 0.098% | |
| CA Fendanes She Loves Me She Loves Me Not V Jerdan | 6 | 5 | 0.098% | |
| CA Am Ch Shady Crk N Moon Rvrs Im N Uptown Girl | 6 | 5 | 0.098% | |
| CA Bis BISS Am Can Ch Sasdania-Vitag's Frozen Asset | 6 | 5 | 0.098% | |
| CA Am Ch Reimroc Solidly Rojon | 6 | 6 | 0.098% | 2 paths through both sides |
| CA Am Ch Elan's New Years Resolution | 6 | 6 | 0.098% | 2 paths through both sides |
| CA BIS BISS Jpn & Am Ch Hauerdane's Pump-N-Iron | 7–9 | 6–8 | 0.092% | Deep foundation dog, 18 cross paths |
| CA Am Ch Avanti's Royhl Rogue | 6–9 | 8 | 0.070% | Deep foundation dog, 14 cross paths |
| CA BISS Am Ch Sarmac's I've Arrived | 6–9 | 7–9 | 0.065% | 10 paths through both sides |
| Total Wright's COI (9 gen depth) | 4.04% | 123 CAs, 618 paths — well below 6.25% (first-cousin equivalent) | ||
Key Structural Findings
COI revision: 2.1% → 4.04%. The original estimate of ~2.1% was based on incomplete data in generations 8–9. With complete ancestry through generation 9, the actual Wright's COI is 4.04%. The increase comes primarily from deep foundation dogs — Honey Lane's Highlight alone contributes through 120 separate cross-paths (0.27% total), and Don-Lu's Preferred Risk adds another 40 paths (0.13%). These are the breed's structural bedrock, appearing in nearly every fawn/brindle pedigree.
Parent COI revisions. Piper's own COI went from 0.0% (at AKC depth) to 1.00% with 56 common ancestors — still very low, confirming her as an excellent outcross foundation. Ezra's own COI is 2.50% (48 common ancestors), driven primarily by Nash Bridges Royhl (0.34%) and the Krisda/Sarmac cluster. Both parents are well below breed average.
Still an effective outcross. At 4.04%, this cross remains well below 6.25% (first-cousin equivalent) and far below the breed average of 10–15% at this depth. The structural diversity between Ezra's Scandinavian/Diplomatic's lines and Piper's American Longo/Fendane lines is real and significant.
Diplomatic's Umberto di Visconti (DKCh SCH NCH NordCH) appears 3× internally in Ezra's sire pedigree but traces to the Grand Fawns and Airways kennels in Scandinavia — lines that do not appear at accessible depth in Piper's American pedigree. This remains a genuine source of new genetic diversity.
Avanti's All For One Elan (0.439% via 8 paths) remains the single largest named contributor, entering through both Ezra's dam cluster and Piper's Danekraafts/Elan lines.
The Fendane full-sibling pair — Eb N Prf So You Wanna Play With Magic (Piper) and Winter Is Coming (Ezra) — drive the two largest single-path contributions (Saul's TM and Allie-Gator at 0.39% each).