Muscles make up about 40 percent of total body weight in most vertebrates.
Notes on verification
Multiple independent physiology sources (peer-reviewed, textbook, encyclopedic) confirm ~40% figure for humans and cite comparable percentages across vertebrates, though exact range varies (30-50%) by species and source. [cascade flags: aggregator_dropped_primary_exists | tier=silver indep_score=0.983 clusters=3 claim_tier=notable]
Sources
- 14 Fun Facts About the Muscular System - Healthline (seed:health_and_medicine)
- https://pubmed.ncbi.nlm.nih.gov/25294644/ (corroboration)
- https://www.ncbi.nlm.nih.gov/books/NBK532258/ (corroboration)
- https://www.ebsco.com/research-starters/anatomy-and-physiology/muscles-vertebrates (corroboration)
- https://link.springer.com/chapter/10.1007/978-3-642-96211-0_5 (corroboration)