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T. rex Lived Longer, Grew Slower Than Previously Believed

1/15/2026

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Summary

Story summary

A PeerJ study shows Tyrannosaurus rex lived longer and grew more slowly than previously thought.
Researchers analyzed 17 fossil specimens and used cross-polarized light to reveal growth rings.
They estimate maximum size at about 35 to 40 years, later than earlier 20 to 25 years.
The findings could prompt reevaluation of growth patterns in other dinosaurs.
The study advances paleontology by improving understanding of Tyrannosaurus rex's life cycle.

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Story summary

A PeerJ study shows Tyrannosaurus rex lived longer and grew more slowly than previously thought.
Researchers analyzed 17 fossil specimens and used cross-polarized light to reveal growth rings.
They estimate maximum size at about 35 to 40 years, later than earlier 20 to 25 years.
The findings could prompt reevaluation of growth patterns in other dinosaurs.
The study advances paleontology by improving understanding of Tyrannosaurus rex's life cycle.