How Do Zooarchaeologists Know How Old an Animal Was When It Died?

Here's a question zooarchaeologists deal with every day: how do you figure out the age of an animal that died thousands of years ago, when all that's left is a bone? It turns out, bones carry their age in two very clever ways — and learning to read them is one of the zooarchaeologist's exciting skills.

Method 1: Reading the Teeth

Just like in humans, animal teeth go through predictable stages of eruption and wear throughout their lives. A goat's first molar appears at a certain age. It starts to show wear at a predictable rate. By looking at which teeth are present and how worn they are, zooarchaeologists can estimate an animal's age — even thousands of years after its death.

Think of it like this: a brand-new tooth with no wear means a young animal. A heavily worn tooth with exposed dentine means an older one. A tooth that hasn't erupted yet means a very young animal. Each stage is a clue, and together they paint a picture of the animal's life stage at the moment it died.

Method 2: Bone Fusion

Young animals have bones that are still growing. At the ends of long bones — like the legs — there are growth plates, areas of softer tissue that gradually harden and fuse as the animal matures. Different bones fuse at different ages, and this happens on a predictable schedule. A radius bone fuses at 6 months in a goat; a humerus at 48 months. By looking at which bones are fused and which aren't, zooarchaeologists can build an age profile of an entire ancient herd.

What Age Profiles Reveal About Ancient Life

Put hundreds of bones together from one site, and you can reconstruct not just one animal's age but the demographics of an entire ancient herd — how many immature individuals, how many adults, and from that, you can infer what the herd was being used for: dairy, meat, wool, work. The bones don't just tell you what animals were there. They tell you the entire economic story of how those animals lived and died.

Why This Is Like Animal Forensics

This is essentially animal forensics — using physical evidence to reconstruct events from the past. Just as a detective examines clues at a crime scene, a zooarchaeologist examines bones at an excavation site. The worn molar is a clue. The unfused growth plate is a clue. The pattern of which bones are present is a clue. Together, they tell a story that no other historical document could preserve.

The ZooArchaeology for Kids books include anatomical atlases and activity pages that teach children to identify different bones — which makes this methodology suddenly very real and hands-on. Learning the names and shapes of bones isn't just memorisation: it's the first step to reading the stories they contain.

These stories and discoveries come alive in the ZooArchaeology for Kids book series — written by Dr. Linoy Namdar, a real working zooarchaeologist. Perfect for curious children ages 6–16, with vivid illustrations, anatomical atlases, and activity pages.

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