BEAC: an epigenetic clock for estimating chronological age in birds
The BEAC is an epigenetic clock built from known-age king penguins and tested in nine other bird species; it estimates chronological age, not lifespan or health outcomes. [1]
Automatic summary · not editorially reviewed
The key findings
The BEAC was established from genome-wide enzymatic methylation sequencing data of known-age king penguins and uses a panel of 24 primer pairs. [1]
In king penguin training data the clock reached R²=0.88 and MAE=1.7 years (n=78); in testing data R²=0.79 and MAE=2.3 years (n=41). [1]
Cross-species validation across 180 samples showed age-associated methylation signals in nine additional bird species across seven clades. [1]
The source at a glance
- Study type / format
- Abstract of a clock-development and cross-species validation study
- Population / context
- King penguins of known age and nine additional bird species across seven clades.
- Summary based on
- Study abstract
- Publication status
- Preprint · peer-review status not confirmed
- Original publication
- August 17, 2026
Clock built from known-age king penguins
The authors describe most epigenetic clocks as developed for mammals. They present the Bird Epigenetic Ageing Clock (BEAC) for estimating chronological age in birds. It was established using genome-wide enzymatic methylation sequencing data from king penguins (Aptenodytes patagonicus) of known age. The clock condenses age-informative signals into a bisulfite amplicon sequencing panel of 24 primer pairs, which the authors call a cost-effective alternative to sequencing-intensive approaches.
Supporting source [1]
Accuracy in king penguin training and test data
In independent king penguin training data the clock reached R²=0.88 with a mean absolute error (MAE) of 1.7 years (n=78). In testing data it reached R²=0.79 with an MAE of 2.3 years (n=41). The abstract also reports negligible batch effects, high longitudinal consistency and resilience to reduced sample size or missing loci. These are performance figures for age estimation, not evidence about survival or health.
Supporting source [1]
Cross-species test across nine bird species
Cross-species validation across 180 samples showed that the clock captures age-associated methylation signals in nine additional bird species across seven clades. The authors conclude that a single set of loci can be predictive of ageing across multiple bird species and describe the clock as a transferable framework for avian clocks. The abstract does not report per-species accuracy or whether the clock predicts anything beyond chronological age.
Supporting source [1]
How to interpret this
This is an abstract; the full text was not reviewed. The clock estimates chronological age, and the abstract reports no lifespan, health or causal outcomes. Per-species accuracy and study details beyond those stated are not given.
Based on the study abstract; the full paper, tables and supplementary data were not reviewed.
Source & supporting passages
Hukkanen M, Jarman S, Budd A, Nitta Fernandes FA, Ambrosini R, Anderson C, Bardon G, Berry O, Bitton P, Bugnyar T, Caprioli M, Carlile N, Cecere JG, Cossin-Sevrin N, Costanzo A, Corregidor-Castro A, Davis LR, van Dijk E, Elsner M, Elliott KH, Ferrer Obiol J, Frigerio D, Gardoni N, Helsen P, Hofer M, Kleindorfer S, Lammers J, Léandri-Breton D, Massen J, McIvor GE, Meyer BS, Morel A, Morganti M, Paciello E, Paris J, Pilastro A, Pihlflyckt L, Plaza P, Polanowski AM, Puhakka A, Roman L, Romano A, Rubolini D, Shetty A, Sumasgutner P, Taff C, Thornton A, Trucchi E, Vitousek M, Westerlund S, Whelan S, Zahn S, Kaprio J, Le Bohec C, Ollikainen M, Cristofari R. · europepmc.org · August 17, 2026