Overview
- The best-supported composite growth curve indicates a gradual trajectory to asymptotic size at roughly 35–40 years, revising earlier 20–25 year estimates.
- Within individuals, growth-ring spacing varied widely from year to year, suggesting flexible growth tied to food availability and environmental conditions.
- An external fundamental system was identified only in the largest animals, indicating true cessation of lengthwise growth in some specimens.
- Two specimens, including the well-known 'Jane' and 'Petey,' were statistical outliers, leaving open whether they represent different taxa or non-taxonomic factors.
- The authors say standard dinosaur skeletochronology protocols should be updated, and a co-author notes the findings point to possible lifespans of about 45–50 years.