Association of protein intakes and variation of diet‐scalp hair nitrogen isotopic discrimination factor in Papua New Guinea highlanders

Abstract

We hypothesize that a combination of several factors, which presumably included urea recycling and amino acid and protein recycling and/or de novo synthesis during metabolic processes, altered the Δ(15) N values of the participants.

Hairs in old books isotopically reconstruct the eating habits of early modern Japan

“…Another advantage pertains the technical and ethical easiness of hair collection from the book, which is not usually be regarded as destruction of cultural properties in contrast to the case of archaeological skeletons. Moreover, isotopic studies of contemporary people are usually done with hair samples because of the technical and ethical easiness of hair collection 21 – 25 ; thus, direct comparison of the isotope ratios with the same tissue-specific TDF is possible when the hairs are used for the study of past people. This is important given that inter-tissue and inter-species variations in TDF were recently shown as more considerable than previously believed based on earlier studies 24 , 25 , 45 – 47 .…”

“…Moreover, isotopic studies of contemporary people are usually done with hair samples because of the technical and ethical easiness of hair collection 21 – 25 ; thus, direct comparison of the isotope ratios with the same tissue-specific TDF is possible when the hairs are used for the study of past people. This is important given that inter-tissue and inter-species variations in TDF were recently shown as more considerable than previously believed based on earlier studies 24 , 25 , 45 – 47 . Books published in the early modern Japan remain massively available 28 , 29 , which has the potential to be used as ideal samples for large data analyses to test numerous hypotheses on regional variations and temporal changes of the eating habits and cuisines in the early modern Japan 3 – 7 .…”

“…Isotope analysis has also been applied by numerous studies to the reconstruction of past human eating habits, mostly using collagen extracted from skeletons 16 – 20 , which are neither abundant nor easily accessible. On the other hand, hair isotope ratios have typically been used to examine the regional variation of contemporary people’s eating habits, since hair collection is technically and ethically easy and hair-specific TDF is already known 21 – 25 . Consequently, if hairs of the past people can be collected with records on time and places, their eating habits can be accurately estimated and compared to those of contemporary times with the same TDF.…”

Evidence for herbivorous cave bears (Ursus spelaeus) in Goyet Cave, Belgium: implications for palaeodietary reconstruction of fossil bears using amino acid δ15N approaches

“…As d 15 N values of individual amino acids may reflect aspects other than diet, such as physiology or possibly illness (Styring et al, 2010;Reitsema, 2013;Naito et al, 2015), the observed partitioning in PCA may represent some difference in physiological traits among the fossil bears ( Fig. 6 and S2).…”

Carbon and nitrogen stable isotopic offsets between diet and hair/feces in captive chimpanzees

“…Understanding the degree of isotopic offsets in chimpanzees is essential in order to compare the isotopic ratios of a chimpanzee's tissues and food sources. The carbon and nitrogen offset values have been particularly well studied in humans; however, only a few studies have been reported for nonhuman primates (Table ) …”