Extended Data Fig. 5: X-ray diffraction (XRD) analysis of bioapatite lattice parameters, microstrain, and crystallite size (CS) in fish tooth enameloid.
From: Evidence for the cooking of fish 780,000 years ago at Gesher Benot Ya’aqov, Israel
a, Association between lattice parameters ratio (c/a) and estimated stoichiometric coefficient (x) in cyprinid teeth used in this study (n = 49) and in Palaeozoic and Mesozoic (400‒200 Ma) fossil fish teeth (n = 10)85,86,87,88. b, Lattice parameters of cyprinid pharyngeal teeth analysed in this study and in Palaeozoic and Mesozoic fossil fish teeth85,86,87,88. c, Association between enameloid microstrain and CS in: fresh unheated molariform teeth (n = 4), teeth from whole fresh fish experimentally heated to 200‒600 °C (n = 11), fossil cyprinid teeth of GBY (n = 31), and Erq-el-Ahmar (n = 2). Note that moderate heating (200‒500 °C) increases CS to values of 18 to 23 nm (compared to CS ≈ 17 nm in unheated teeth), whereas natural diagenesis decreases CS and increases microstrain. d, Relation between enameloid microstrain and CS of molariform teeth in: fresh unheated fish, fish cooked in the oven (low heat), and fish cooked in the fire (up to 900 °C). The curved stippled red line marks the trend between microstrain and CS. Note that above a temperature of 600 °C the CS, value strongly increases, reaching a maximum value of up to 68 nm in calcinated teeth, while microstrain decreases below a value of 0.20%.
