Diet and mobility

Chemical evidence in bones

The diet and mobility of people who lived in the past can be traced through the chemical analysis of the skeleton. The chemical elements enter our body via food.

The isotopes of carbon and nitrogen reflect the types of food consumed by ancient populations, while the isotopes of strontium and oxygen reflect their mobility during their lifetime.

What are isotopes?

The isotopes are the variants of a chemical element in nature. The number of isotopes varies among plants, animals, fish and humans and depends on their position in the food chain.

For instance, the ratios of nitrogen and carbon isotopes are lower in plants and increase as we move up the food chain.
Through the combined study of isotopes, we can detect the food preferences of an individual.

Isotopic Analysis Laboratory

Processing of bones
First, a small bone sample is removed from the skeleton. Then, collagen, a protein that contains carbon and nitrogen isotopes, is isolated from the bone sample.

Processing of teeth
In the case of teeth, serial sectioning in layers is performed following the development of the tooth. The extraction of collagen from each layer assists in the estimation of the individual’s diet in specific periods of time.

Diet

Teeth, from the moment they are formed, do not remodel, which is why they provide information about diet during childhood.

Bones, on the other hand, remodel constantly. This is why the information we receive from the isotopic analyses refers to the final years of an individual’s life.

Breastfeeding

By analyzing stable isotopes, we also study the duration of an individual’s breastfeeding in the past.

This is due to the fact that during breastfeeding, infants have higher isotopic ratios than their mothers. When the consumption of breast milk stops, the isotopic ratios match those of other adult individuals.

Mobility

By analysing the stable isotopes of strontium and oxygen, we can study human mobility.

The value from a tooth reflects the environment of childhood, whereas the value from a bone reflects the environment of adulthood.

If these values differ significantly, we can assume that the individual was born in a place and migrated at some point in their adult life.

The hunter-gatherer of Astypalea

The memory keeper

The mother

The Lacedaemonian

The woman with the trepanned skull

The nobleman

The lady

The history observer

The city dweller

The warrior

Diet and mobility

Chemical evidence in bones

What are isotopes?

Isotopic Analysis Laboratory

Diet

Breastfeeding

Mobility

From
bone fragments
to human
stories

The hunter-gatherer of Astypalea

The memory keeper

The mother

The Lacedaemonian

The woman with the trepanned skull

The nobleman

The lady

The history observer

The city dweller

The warrior

Diet and mobility

Chemical evidence in bones

From bone fragments to human stories

From
bone fragments
to human
stories