Deming Yang

Amnerican Museum of Natural History · Anthropology

Neogene and Pleistocene African suids displayed convergent evolutionary trends in the third molar (M3) morphology, with increasingly elongated and higher crowns through time. While these features can prevent premature loss of masticatory functionality and potentially increase long-term reproductive success, changes in dental occlusal traits such as...

Objectives Enamel prism decussation, which manifests as Hunter-Schreger Bands (HSB), is considered a mechanism to mitigate crack propagation. During the chewing cycle, the ‘functional’ cusps that are involved in Phase II crushing and grinding experience more complex patterns of stress than do those that ‘guide’ the molars into occlusion (Phase I)....

Plant wax n-alkane chain length distribution and isotopes have been studied in modern ecosystems as proxies to reconstruct vegetation and climate of the past. However, most paleo-proxies focus on either concentrations or isotopes, whereas both carry complementary information on the mixing sources. We propose a multi-source mixing model in a Bayesia...

Strontium isotope ratios ( ⁸⁷ Sr/ ⁸⁶ Sr) of incrementally grown tissues have been widely used to study movement ecology and migration of animals. However, the time scale of ⁸⁷ Sr/ ⁸⁶ Sr incorporation from the environment into tissue and how it may influence data interpretation are still poorly understood. Using the relocation of a zoo elephant ( Lo...

Although modern humans left Africa multiple times over 100,000 years ago, those broadly ancestral to non-Africans dispersed less than 100,000 years ago¹. Most models hold that these events occurred through green corridors created during humid periods because arid intervals constrained population movements². Here we report an archaeological site—Shi...

Strontium isotope ratios (87Sr/86Sr) of incrementally grown tissues have been used to study movement/migration in extinct megaherbivores. Despite growing interest in this tool, two challenges remain. The first is how the same primary input signal is recovered from different archives, such as tooth enamel and dentin, with different sampling methods....

Submerged macrophytes are important indicators of the state of shallow freshwater ecosystems. Reconstruction long‐term changes in submerged macrophytes remains a challenge in paleoecology. Here, the relative biomass (mass weight) of different plants to sedimentary organic matter in a shallow lake in central China was estimated using a Bayesian mult...

Some 25 years ago Dan Fisher with Dave Fox suggested that primary isotope inputs could be modified during processes such as maturation of enamel. Subsequent work on modern mammals shows that isotope incorporation can be affected by multiple metabolic pools that can have isotope turnover half-lives of up to 0.5 years, and that maturation of enamel v...

This work presents a comprehensive evaluation of three sources of signal attenuation of ⁸⁷Sr/⁸⁶Sr in elephant enamel and a proven workflow that facilitates the interpretation of animal movement/migration. It addresses key challenges in obtaining and interpreting intra-tooth ⁸⁷Sr/⁸⁶Sr data, and enables robust estimations of ⁸⁷Sr/⁸⁶Sr intake history...

Measurements of oxygen and hydrogen stable isotope ratios (δ¹⁸O and δD) in meteoric waters provide insight to overlapping effects of evaporation, precipitation, and mixing on basin scale hydrology. This study of waters collected between 2016 and 2021 in the Turkana Basin, northern Kenya, uses δ¹⁸O and δD to understand water balance in Lake Turkana,...

Strontium isotope ratios (⁸⁷Sr/⁸⁶Sr) of incrementally grown tissues have been used to study movement and migration of animals. Despite advances in characterizing ⁸⁷Sr/⁸⁶Sr turnover [1], the 2-D geometry of turnover in the tooth enamel is still poorly understood. The relocation of a zoo elephant (Loxodonta africana) named Misha provided an exception...

Paleontological fieldwork at the late Miocene localities of the Lemudong'o Formation (~6 Ma) in southern Kenya, can contribute to understanding of ape/early hominin paleoecology and evolution. The primary fossiliferous localities are Lemudong'o 1 (LEM1) and Enamankeon (ENK), which are ~5 km apart. Fossil collecting efforts can be grouped into three...

How animals respond to seasonal resource availability has profound implications for their dietary flexibility and realized ecological niches. We sought to understand seasonal dietary niche partitioning in extant African suids using intra-tooth stable isotope analysis of enamel. We collected enamel samples from canines of red river hogs/bushpigs (Po...

Strontium isotope ratios (87Sr/86Sr) of incrementally grown tissues have been widely used to study movement ecology and migration of both extant and extinct animals. However, the timescale of 87Sr/86Sr incorporation from the environment into tissue and how it may influence data interpretation are still poorly understood. Using the relocation of a z...

Hydrogen isotope ratios of terrestrial plant wax lipids have been extensively used to interpret changes in hydroclimate and rainfall regimes. However, challenges remain in the quantitative reconstruction of precipitation δ2H due to large uncertainties associated with the apparent fractionation factor (εa) between plant wax lipids and precipitation....

Plant wax n-alkane chain length distribution and δ13C have been studied in modern ecosystems as proxies to reconstruct vegetation and climate of the past. Studies on modern plants often report both chain-specific n-alkane concentrations and δ13C values. However, studies on geological archives interpret only one proxy, while both carry crucial infor...

Plant wax n-alkane chain length distribution and δ13C have been studied in modern ecosystems as proxies to reconstruct vegetation and climate of the past. Many studies of modern plants report both chain-specific n-alkane concentrations and δ13C values. However, studies on geological archives often interpret only one proxy, while the two are tightly...

Intra-tooth stable isotope variations have been used to interpret seasonality and aridity in paleoenvironmental reconstructions of paleontological and archeological sites. However, most intra-tooth datasets only permit qualitative interpretations of seasonality, because the measured signal is attenuated due to the duration of enamel mineralization...