Ref ID:	24698
Ref Type:	Book Section
Authors:	Krueger, Harold W. Sullivan, Charles H.
Title:	Models for carbon isotope fractionation between diet and bone
Date:	1984
Source:	Stable isotopes in nutrition
Place of Publication:	Washington, D.C.
Publisher:	American Chemical Society
Abstract:	original article that suggested there is a difference between collagen values as a result of protein intake vs. carbohydrate and lipid intake. from Lee-Thorp et al 1989-JAS article The difference between the delta<sup>13</sup>C values of collagen and apatite (referred to as the apatite-collagen spacing) changes with trophic level because different macronutrients (proteins, carbohydrates, fats) assume greater or lesser importance in different diets. Thus \bherbivores\b derive protein from plant proteins and transamination of keto-acids (derived from carbohydrates), and energy from carbohydrates. \bCarnivores\b derive protein directly from prey protein (mainly meat), and energy from prey lipids and proteins. In both cases collagen reflects the growth aspects (protein in diet) and apatite the energy aspect of diet (diet as a whole). Since fats are depleted in <sup>13</sup>C (isotopically lighter) relative to proteins and carbohydrates of the same plant or organism (DeNiro and Epstein 1978-carbon in animals), an increase in their utilization for energy results in relatively more depleted values for apatite-carbonate. Consequently they are closer to collagen values, resulting in smaller apatite-collagen spacing values. herbivores= apatite-collagen spacing is +7‰ carnivores= apatite-collagen spacing is +3‰
Date Created:	7/5/2001
Editors:	Turnland, J. E. Johnson, P. E.
Volume:	258
Page Start:	205
Page End:	222
Series Title:	American Chemical Society Symposium