Organic Residue

Question 1

Residues

Answer 1

• Organic materials processed in containers
• Pitchers, tar, resin, and bitumens adhering to artefacts (weapons, tools, decorative objects, human remains)

Question 2

Vessels

Answer 2

• Contents stores or processed in pottery
• Single product or accumulation of different uses, content preserved in situ
• Carbonised, encrusted residues adhering to the interior or exterior of vessels
• Absorbed residues survive in 80% of domestic cooking pottery

Question 3

3 classes of organic residue

Answer 3

• Triacylglycerol
• Phospholipids
• Sterols

Question 4

Simple lipids vs complex lipids

Answer 4

Simple:
- Glycerol head with fatty acid tail

Complex:
- Complex compounds in the place of glycerol
- Hydrophobic tail link to form cell wall

Question 5

Fatty acids

Answer 5

• Most have a chain of an even number of 4-28 carbon atoms
• Rarely occurs as free molecules in living organisms
• Saturated: no double carbon bonds
• unsaturated: variable number of carbon atom bonds
• Both the length of the chain and the number of double bonds determines the solubility and melting point of the lipid

Question 6

Lipid Preservation

Answer 6

• Although lipids are robust, they tend to degrade over time
• Largue molecules degrade to shorter molecules
• Shorter molecules are more soluble and may be lost
• Veg oils, animal fats, fish oil, milks

Question 7

How to analyse lipids?

Answer 7

GC-MS (gas chromatography - mass spectrometry / gas chromatography - isotope ratio mass spectrometry)

Question 8

Chromatography

Answer 8

• Identified and quantified organic residues/lipids are presented on a chromatogram

Question 9

Identification of lipids

Answer 9

• Many animals have the same types of fatty acids but with different carbon isotope ratios
• Reflecting the dietary source used for lipid synthesis
• Greater proportion of dietary carbohydrate is routed to adipose fat than to milk fat

Question 10

Early Pottery and Plant Processing in Holocene Northern Africa

Answer 10

• invention of pottery opened up new ways to process plants
• Unlock potential of wild plants as foodstuff
• Pottery developed around 10,000 CE
• Used in Northern Africa by semi-sedentary hunter-gatherers
• Pottery also emerged independently in East Asia around 14,000 BCE

Question 11

Lactaste persistence

Answer 11

• Genetic evidence shows all analysed early neolithic individuals were lactoste intolerant
• Lactaste persistance only more widespread in Bronze and Iron Ages
• Under conditions of famine / increased pathogen exposure of disadvantageous driving gene for lactaste persistence
• Calcium assimilation hypothesis
• Beaker phenomenon

Question 12

Dairy Diaspora

Answer 12

• 11,000-10,000 YA: neolithic culture develops in the middle east. This is the start of agriculture and possibly dairy animal domestication
• 8,400 YA: Neolithic spreads to Greece
• 7500 YAl Lactaste persistence emerges in central Europe: a piece of a roughly 7000 year old sieve used to make cheese was found
• 6,500 years ago: well developed dairy economy established in central europe