Clive N. Trueman

Bio: Clive N. Trueman is an academic researcher from University of Southampton. The author has contributed to research in topics: Population & Otolith. The author has an hindex of 41, co-authored 111 publications receiving 4609 citations. Previous affiliations of Clive N. Trueman include University of Portsmouth & National Oceanography Centre, Southampton.

Trace elements in recent and fossil bone apatite

Abstract: The biomineral component of bones and teeth is synthesized within the body, under direct physiological control, and therefore the chemistry of bone (including the trace element chemistry) reflects aspects of the animal’s biology, particularly the trace metal load, but also the state of metabolism of specific trace metals. Bone mineral is relatively reactive due principally to its small crystal size, and consequently bone is unstable once removed from the body. Bone undergoes a complex set of diagenetic processes post mortem, which generally lead to dissolution, however bones and teeth are relatively common components in (post-Ordovician) rocks. The trace element content of bone is susceptible to alteration immediately upon exposure, and while these changes reduce the usefulness of ancient bone as a monitor of the physiology or diet of ancient animals the trace element composition of ancient bone can yield useful paleoenvironmental information. This chapter is concerned principally with archaeological and geological applications of trace element chemistry of bone, rather than physiological or medical implications. The inorganic (mineral) component of bone is carbonated calcium phosphate (Ca10(CO3,PO4)6(OH)2), similar to the mineral dahllite. The calcium phosphates form the vast majority of all vertebrate hard tissues (Young and Brown 1982), and exhibit a very wide range of physical and chemical properties. Stoichiometric hydroxyapatite is not known biologically, and is only produced artificially or geologically at high temperature and pressure. The mineralogy of bone, dentine, and enamel is reviewed in Elliott (this volume). Kohn and Cerling (this volume) highlight the fact that apatite crystal size and shape varies between bone and enamel, and point out that variations in crystal size are in part responsible for the greater diagenetic susceptibility of bone compared to enamel. Bone crystallites are essentially plate-shaped, with average dimensions of 350–400 A × …

The effect of growth rate on tissue‐diet isotopic spacing in rapidly growing animals. An experimental study with Atlantic salmon (Salmo salar)

Abstract: The difference in isotopic composition between a consumer’s tissues and that of its diet is a critical aspect of the use of stable isotope analyses in ecological and palaeoecological studies. In a controlled feeding experiment with the Atlantic salmon, Salmo salar, we demonstrate for the first time that the value of tissue-diet isotope spacing in nitrogen in a growing animal is not constant, but varies inversely with growth rate. The value of tissue-diet isotopic spacing in N reflects N use efficiency. Thus, in salmon, growth rate is accompanied by, or requires, increased N use efficiency. The total range in tissue-diet isotopic spacing in N seen in the experimental population of 25 fish was 1%, approximately 50% of the total trophic shift. Mean equilibrium tissue-diet isotopic spacing (� standard deviation) in salmon averaged 2.3% (� 0.3%) and 0.0% (� 0.3%) for N in muscle and liver, respectively, and 2.1% (� 0.1%) and 1.6% (� 0.3%) for C in muscle and liver, respectively. Feeding with a mixed dietary source (wheat and fish-meal origin) resulted in tissue-diet isotopic fractionation in both C and N due to the differential digestibility of food components with distinct isotopic composition. The rate of change in isotopic composition of S. salar tissues was dominated by growth, but the estimated contribution of metabolic turnover to change in tissue N was relatively high for an ectothermic animal at ca. 20–40%. The estimated half-life for metabolic turnover of the tissue N pool was ca. 4 months in both muscle and liver tissue. This is the first study to demonstrate a direct relationship between tissue-diet isotopic spacing in N and growth rate and adds to the growing list of factors known to influence the level of isotopic separation between a consumer’s tissue and that of its diet. Copyright # 2005 John Wiley & Sons, Ltd. Stable isotope analysis (SIA) is commonly used to infer diet and trophic level in ecosystem studies. SIA offers advantages over gut content analysis as a method to study ecosystem structure because the isotopic composition of animal tissue reflects the average diet assimilated over a length of time, usually of the order of weeks to months. SIA may also be performed retrospectively using archived, historic or archaeological materials, 1,2 allowing reconstruction of ecosystem or

Can otolith elemental chemistry retrospectively track migrations in fully marine fishes

Abstract: Otolith microchemistry can provide valuable information about stock structure and mixing patterns when the magnitude of environmental differences among areas is greater than the cumulative influence of any vital effects. Here, the current understanding of the underlying mechanisms governing element incorporation into the otolith is reviewed. Hard and soft acid and base (HSAB) theory is employed to explore the differences in chemical behaviours, distributions and affinities between elements. Hard acid cations (e.g. Mg2+, Li+ and Ba2+) tend to be less physiologically influenced and accepted more readily into the otolith crystal lattice but are relatively homogeneous in seawater. Soft acid cations (e.g. Zn2+ and Cu2+) on the other hand, exhibit more varied distributions in seawater, but are more likely to be bound to blood proteins and less available for uptake into the otolith. The factors influencing the geographical distribution of elements in the sea, and their incorporation into the otoliths of marine fishes are reviewed. Particular emphasis is placed on examining physiological processes, including gonad development, on the uptake of elements commonly used in population studies, notably Sr. Finally, case studies are presented that either directly or indirectly compare population structuring or movements inferred by otolith elemental fingerprints with the patterns indicated by additional, alternative proxies. The main obstacle currently limiting the application of otolith elemental microchemistry to infer movements of marine fishes appears to lie in the largely homogeneous distribution of those elements most reliably measured in the otolith. Evolving technologies will improve the discriminatory power of otolith chemistry by allowing measurement of spatially explicit, low level elements; however, for the time being, the combination of otolith minor and trace element fingerprints with alternative proxies and stable isotopic ratios can greatly extend the scope of migration studies. Among the otolith elements that routinely occur above instrument detection limits, Ba, Mn and Li were deemed the most likely to prove reliable geographic markers in marine species.

The long–term survival of bone: the role of bioerosion

Abstract: Fossil bones (N = 350) spanning more than 350 million years, and covering a wide range of depositional environments, were studied to compare the distribution of microbial destruction features in fossil bones with previously published data sets of bones of archaeological age. The distribution of bioerosion in fossil bones is very different from that found in bone from archaeological sites. Fossil bones typically show little or no bioerosion. Under normal conditions, if a bone is to survive into the fossil record, then rapid bioerosion must be prevented (or halted). This conclusion suggests that early post mortem processes,such as the mode of death, influence the potential of any bone to survive into deep time.

Influence of Diet On the Distribtion of Nitrogen Isotopes in Animals

Abstract: The influence of diet on the distribution of nitrogen isotopes in animals was investigated by analyzing animals grown in the laboratory on diets of constant nitrogen isotopic composition. The isotopic composition of the nitrogen in an animal reflects the nitrogen isotopic composition of its diet. The δ^(15)N values of the whole bodies of animals are usually more positive than those of their diets. Different individuals of a species raised on the same diet can have significantly different δ^(15)N values. The variability of the relationship between the δ^(15)N values of animals and their diets is greater for different species raised on the same diet than for the same species raised on different diets. Different tissues of mice are also enriched in ^(15)N relative to the diet, with the difference between the δ^(15)N values of a tissue and the diet depending on both the kind of tissue and the diet involved. The δ^(15)N values of collagen and chitin, biochemical components that are often preserved in fossil animal remains, are also related to the δ^(15)N value of the diet. The dependence of the δ^(15)N values of whole animals and their tissues and biochemical components on the δ^(15)N value of diet indicates that the isotopic composition of animal nitrogen can be used to obtain information about an animal's diet if its potential food sources had different δ^(15)N values. The nitrogen isotopic method of dietary analysis probably can be used to estimate the relative use of legumes vs non-legumes or of aquatic vs terrestrial organisms as food sources for extant and fossil animals. However, the method probably will not be applicable in those modern ecosystems in which the use of chemical fertilizers has influenced the distribution of nitrogen isotopes in food sources. The isotopic method of dietary analysis was used to reconstruct changes in the diet of the human population that occupied the Tehuacan Valley of Mexico over a 7000 yr span. Variations in the δ^(15)C and δ^(15)N values of bone collagen suggest that C_4 and/or CAM plants (presumably mostly corn) and legumes (presumably mostly beans) were introduced into the diet much earlier than suggested by conventional archaeological analysis.

Taphonomic and Ecologic Information Form Bone Weathering

Abstract: Bones of recent mammals in the Amboseli Basin, southern Kenya, exhibit distinctive weathering characteristics that can be related to the time since death and to the local conditions of temperature, humidity and soil chemistry. A categorization of weathering characteristics into six stages, recognizable on descriptive criteria, provides a basis for investigation of weathering rates and processes. The time necessary to achieve each successive weathering stage has been calibrated using known-age carcasses. Most bones decompose beyond recognition in 10 to 15 yr. Bones of animals under 100 kg and juveniles appear to weather more rapidly than bones of large animals or adults. Small-scale rather than widespread environmental factors seem to have greatest influence on weathering characteristics and rates. Bone weathering is potentially valuable as evidence for the period of time represented in recent or fossil bone assemblages, in- cluding those on archeological sites, and may also be an important tool in censusing populations of animals in modern ecosystems.

Strontium Isotopes from the Earth to the Archaeological Skeleton: A Review

Abstract: Strontium isotope analysis of archaeological skeletons has provided useful and exciting results in archaeology in the last 20 years, particularly by characterizing past human migration and mobility. This review covers the biogeochemical background, including the origin of strontium isotope compositions in rocks, weathering and hydrologic cycles that transport strontium, and biopurification of strontium from to soils, to plants, to animals and finally into the human skeleton, which is subject to diagenesis after burial. Spatial heterogeneity and mixing relations must often be accounted for, rather than simply ``matching'' a measured strontium isotope value to a presumed single-valued geologic source. The successes, limitations and future potential of the strontium isotope technique are illustrated through case studies from geochemistry, biogeochemistry, ecology and archaeology.

Multivariate Density Estimation

Abstract: Exploring and identifying structure is even more important for multivariate data than univariate data, given the difficulties in graphically presenting multivariate data and the comparative lack of parametric models to represent it. Unfortunately, such exploration is also inherently more difficult.