Skeletochronology
Definition
Age estimation from growth rings (lines of arrested growth, LAGs) in bone cross-sections. Reliable in reptiles and fish; less so in mammals. Each ring typically represents one annual slow-growth period.
- Structure counted
- Lines of arrested growth (LAGs) in bone cross-section
- Most reliable in
- Reptiles and fish
- Less reliable in
- Mammals
- Ring interval assumed
- One ring per annual slow-growth period
Common questions
Why is skeletochronology less reliable in mammals?+
Mammalian bone remodels continuously through life, which can erase or obscure the earliest growth rings, whereas ectotherms like reptiles and fish preserve their arrested-growth lines much more faithfully.
Which bones are typically sectioned for this method?+
Long bones or small skeletal elements such as phalanges are commonly cross-sectioned and examined under polarised or transmitted light microscopy to count the growth lines.
Related terms
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