Conclusion
In this study, we were able to develop an age estimation model using an epigenetic clock analysis with DNA extracted from fecal samples of wild Indo-Pacific bottlenose dolphins. The accuracy of the age estimation model showed an MAE of 5.08 years, and the error ranges from 10–13% of its lifespan. The results provide a sufficient level of accuracy and could be used in ecological studies such as life history and demography. The accuracy of our model achieved in this study is comparable to studies which used similar gene regions in other species. To the best of our knowledge, this is the first study to have successfully quantified the methylation rates of multiple genes from fecal-derived DNA to estimate age in mammals.