Open Dataset of Developmental Timelines for Corresponding Milestones in Mice, Rats, and Humans

Abstract

Translating developmental time across species is essential for the appropriate design and interpretation of preclinical neurodevelopmental research, yet no open, unified resource currently integrates high-quality developmental milestone data for mouse, rat, and human. Here we present a curated, open-access dataset of general and neurodevelopmental milestones spanning these three species, expanding a previously published rat--human database with newly compiled mouse data. Following a systematic literature search, 783 records covering 371 unique developmental milestones were extracted, standardized to days after fertilization, and validated through a structured curation and quality-control process. Exploratory analyses indicated that the developmental relationship between humans and rodents is markedly non-linear, with milestones becoming increasingly dispersed as development progresses. The observed pattern is consistent with the quarter-power model with an additive constant identified in a companion modeling study. Accordingly, applying a quarter-power transformation to human DAF substantially improved the linearity of developmental trajectories across species. Comparison of body and brain milestone clusters showed no detectable differences in scaling relative to humans, in line with similar underlying rules for somatic and neural development between rodents and humans. The dataset, together with its documented curation methodology, provides a transparent and extensible resource for cross-species developmental translation and a useful tool for informing the generation of animal models.