Table 1 Comparison of mechanical properties pertinent to wear of woody plant tissue versus tooth enamel, phytoliths and quartz grit.

From: Hard plant tissues do not contribute meaningfully to dental microwear: evolutionary implications

Material ID(ref)Species of Seed (family)Hardness (GPa)Elastic Modulus (GPa)Toughness (MPa.m½)
Tooth Enamel31
OrangutanPongo pygmaeus (Hominidae)5.01002.5
Small Seeds5
C4 grassesSporobolus spicatus (Poaceae)0.1253
S. ioclados0.2954.7
Pennisetum stramineum0.567
Cynodon dactylon0.1753.2
Eragrostis sp.0.253.7
C4 sedgeCyperus bulbosus (Cyperaceae)0.163.6
C3 sedgeCarex monostachya0.5856.2
Large Seeds
Orangutan food19,32Mezzettia parviflora (Annonaceae); shell zone II0.499.43.5
Sooty mangabey foodSacoglottis gabonensis (Humiriaceae)0.278.21.4
Chimpanzee foodElaeis guineensis (Arecaceae)0.49.6
Hunter-gatherer foodSclerocarya birrea (Anacardiaceae)0.2659.1
Hunter-gatherer foodRicinodendron rautanenii (Euphorbiaceae)0.2611.12.1
Mineral16,33
PhytolithsAmpelodesmos mauritanicus (Poaceae)2.8200.22
Dactylis glomerata (Poaceae)3.0220.28
Kuwait landscapeQuartz13.5950.7
  1. Hardness and elastic modulus were obtained via nanoindentation; toughness values are from macroscale tests.