Experimental variation is a multi-faceted phenomenon leading to both intra-experimental and inter-experimental incongruencies. Such variation often manifests in nonreproducibility of experiments which is rightfully regarded as an issue in experimental sciences. Nonreproducibility has been attributed to inadequate reporting of methods, sloppiness/honest error, and even misconduct. We hypothesized that, within the field of animal physiology, the most parsimonious explanation for nonreproducibility is inadequate reporting of key methodological details. We analyzed 84 research articles published in five primarily organismal animal physiology journals and assessed compliance for 34 reporting variables referring to biology, experimentation, and data collection/analysis. Our study shows that about one third of necessary information on the methodology is missing. We thus assume that at least within the life sciences, underreporting of key variables can lead to a lack of reproducibility that is independent of the rigor of the study, but rather reflects the lack of rigor of the journal article preparation as well as peer review and publishing.