**Author(s):** Tamura, K; Noshita, K; Nakagawa, T; Kaneda, A; Nakao, H Introduction
Datasets on prehistoric human activities have been used to investigate cultural evolution in the past. Although information included in much of these datasets are coded by experts and aggregated at a population level for cross-cultural studies, data on individual artifacts and biological remains can be efficient in answering questions related to cultural variation within a population and to facilitate transparency by testing different coding schemes. 
Materials and Methods
We digitized over 700 pottery and 1,300 human skulls in prehistoric Japan to construct 3D models. As an example, by quantifying morphological variation in the 3D models of pottery using geometric morphometrics, we investigated the spreading process of pottery associated with the spread of rice farming in the western part of the prehistoric Japanese archipelago. 
Results
Pottery in the same geographical regions, though loosely, formed clusters and clusters in geographically neighboring regions tended to be morphologically similar. 
Discussion
Our results are consistent with the route of the spread of rice farming, suggesting that morphological variation in pottery was at least partly shaped through the process of descent with modification. We further discuss possible applications of our dataset, such as quantifying the relative importance of demic and cultural diffusion in the spread of agriculture.

A new dataset of three-dimensional models in prehistoric Japan

Introduction: Childhood is a period of life unique to humans. Childhood may have evolved through the need to acquire knowledge and subsistence skills. In an attempt to evaluate the importance of learning for the evolution of childhood, previous research examined the increase with age of returns to foraging. Any increase could be due to increases in knowledge or other factors such as body size and strength. Materials and methods: In a population of part time children foragers on the island of Pemba, Tanzania, we collected anthropometric measures such as size and strength (N: 202), estimated knowledge (N: 93) and observed a variety of foraging trips (N trips: 310, N individuals: 116). We estimate the contribution of the different elements to foraging success. Preliminary results: We find that knowledge is important for foraging success 
Clearly defining the relative importance of somatic versus cognitive traits of forager children provides clues about the selective pressures leading to the evolution of early life history traits in our species.

Age specific foraging success and importance of ecological knowledge in Pemba, Tanzania

The Cascading Climate Impacts social simulation: Future of Food 

While group-living can increase foraging efficiency and feeding consistency, individual variation in behaviour can cause disparity in food intake among groupmates. For example, bolder individuals may secure more food if they are more exploratory or are willing to take risks to obtain food items. Temperature variation may further modulate phenotypic variation among groupmates and alter levels of feeding disparity within groups. 
We examined the effects of ambient temperature on group foraging in a social catfish, the bronze corydoras (Corydoras aeneus). Groups of 30 fish were placed within large mesocosms and were observed for feeding behaviour at both of 24°C or 28°C, with at least two weeks acclimation to each temperature. Feeding behaviour among individuals within groups was highly repeatably, with the same individuals being consistently first to feed when presented with food items, even when the same groups were tested across temperatures (R = 0.467). Temperature increased group activity and feeding rate, with groups finding food quicker at the warmer temperature, even though groups were more cohesive (individuals closer together) at the cooler temperature. Together, these data highlight individual variation within a group foraging context, whereby specific individuals are more successful at securing food than their groupmates. This will have implications for the relative costs and benefits of group membership for individuals.

Investigation into the effect of temperature on social foraging in Corydoras aeneus

Rice (Oryza sativa L.) is one of the important cereal grains and a staple food for more than 50% of the world’s population. Increases in global temperatures have a negative impact on crop productivity. Plants undergo a variety of physiological and biochemical changes as a result of temperature stress in order to adapt to higher temperatures. In this study, we have used 204 accessions from the Bengal and Assam Aus Panel (BAAP). A total of eight replicate plant per accession were grown. All plants were grown in the greenhouse until maturity; thereafter, five replicate plants were randomly selected, their panicles at anthesis stage marked and were transferred to large growth room at 38°C for 24 hours to assess high-temperature treatments. Three replicates plants were not heat treated. Fertility was assessed as the proportion of flowers filled. Heat treatment significantly (P&lt;0.0001) reduced fertility by 17.4% on average and there was a significant (P&lt;0.0001) differences among accessions. In addition to that, there was a significant (P&lt;0.001) interaction between accession and treatment. Heat tolerant cultivars have been identified including the aus reference cultivar DJ123. Genome Wide Association Studies (GWAS) using 2 million SNPs will be used to identify QTLs and candidate genes associated with heat tolerance in the BAAP.

Genotypic Variation in Heat Tolerance in Aus Rice During the Flowering Stage 

Animal bite force is an ecologically relevant performance trait, crucial for individual fitness through its impact on food ingestion and intraspecific agonistic interactions. Despite its popularity in vertebrates, bite force has only recently begun to be measured across the huge diversity of insects. Bite force studies generally use either in vivo measurements or forces modelled based on muscle physiological cross-sectional area (PCSA), and very rarely compare both. PCSA can be measured in a variety of ways, in particular in insects, which have never been thoroughly compared. Here we compare several digitally computed estimates of PCSA (and its components muscle volume and fiber length) in the major mandibular adductor muscle of Schistocerca gregaria, together with an experimental baseline estimate. This experimental estimate relies on dissecting out the muscles, weighing them, dissolving fiber bundles in acid and measuring fibre length. The digital estimates are based on CT scans of the heads, in which it is possible to measure muscle volume, fibre length, and muscle attachment area. After scanning the heads of the specimens and segmenting their mandibular apparatus, we used manual and automated approaches to measure the above mentioned values, to assess the comparability of the various PCSA methods and proxies, as well as the reliability of the automatization process. In addition, using the different PCSA estimates and muscle stress values from the literature, we model bite forces, which we compare to in vivo measurements from the same individuals.

Modelling bite force in insects: comparison of different PCSA approaches with in vivo measurements

Mandibular kinetics and associated occlusal relations have been a significant focus of physiological studies of mammalian mastication. However, soft tissue deformations of the masticatory apparatus are essential to mastication. Whereas the jaw muscles, ligaments and temporomandibular joint (TMJ) articular disc are vital for jaw movements, perioral muscles and the tongue are key to bolus management and transport. We synthesize deformations of these soft tissue structures as the jaw moves during chewing and propose future avenues of research investigating soft tissue dynamics during mastication. Jaw muscles shorten 5-10% and cheek muscles over 15% during mastication, and their bulging creates pressure on adjacent bones and ligaments. Muscle contraction moves and loads the TMJ, causing the disc and capsule to elongate anteroposteriorly during jaw closing. During jaw opening, muscles lengthen, stretching aponeuroses 4-5%. Chewing side, food hardness, regional and individual differences all modify these effects. The most important soft tissue for mammalian mastication is, however, the tongue, and it undergoes the largest deformations. There are differences in how various species use the tongue during mastication, but all species examined exhibit regional complexity in the amplitude and timing relative to jaw movements. In pigs, for example, the anterior tongue lengthens as the jaw closes, reaching maximum length around minimum gape, then quickly shortens as jaw opening begins. Posterior regions lengthen during jaw closing and opening but shorten much later during opening. Synthesizing these functional roles emphasizes the significance of soft tissue mechanics in masticatory performance.

No Bones About It: Soft Tissue Dynamics during Mammalian Mastication

Vertebrate feeding is a complex process with multiple aspects of integration, including among anatomical systems and physiologic levels. Success in feeding, both in enhanced performance and avoidance of failure, is a mission-critical function for all animals. Hiiemae and Crompton (1985) argued for this integration as the basis of understanding vertebrate feeding in general, and mammalian feeding in specific. The return to this perspective within the comparative biology/ biomechanics/ evolution community is reflected in the enthusiasm for this symposium . 

Feeding—from ingestion through mechanical and chemical processing to transport and the ultimate swallow into the mid-GI system—is a continuous process through what was embryologically and evolutionarily a simple tube. Irrespective of anatomical and evolutionary elaboration, this basic tube is the foundation of the function and survival of the organism. Focusing on specific system functions (prey capture or mastication) provides insight into how natural selection may act on regional anatomy. Yet, consideration of the entire gastrointestinal tract and its outgrowths is necessary to understand how natural selection operates on the feeding performance of the organism as a whole. 

Neurophysiologic integration produces the function or behaviour of feeding. Performance in feeding is ultimately a feedback loop, taking sensory input from soft tissues and bones and converting that information into muscular activation in the central nervous system (CNS), including the brain stem and the cerebral cortex. Focusing on individual parts or specific levels of this elaborate system has provided an essential detail of how the system works. Integration among these individual functional components as well as consideration of downstream gastrointestinal structure and function may yield further insights into fundamental constraints and key evolutionary pressures on this essential system. Mammalian feeding is an exemplar of how both anatomical and physiologic integration have provided both the basis for the variation in mammalian evolution as well as the limits on what is possible. 


Hiiemae KM, Crompton AW. Mastication, food transport and swallowing. In: Hildebrand M, Bramble D, Liem K, Wake D, editors. Functional Vertebrate Morphology. Cambridge: Harvard University Press; 1985. pp. 262–90.








Integration across anatomy and physiology is the basis for understanding feeding behaviour in vertebrates

Cereal grains are among the most important sources of energy for humans and domestic animals, owing to large and nutritious endosperm tissues. We study nuclear organization and chromatin in seeds of cereals using cultivated barley (Hordeum vulgare subsp. vulgare) - a diploid temperate zone model cereal used for both food and feed. Barley has a large genome (2n = 2x = 14, 1C = 5.1 Gbp) with interphase chromosomes organized in Rabl configuration with centromeres and telomeres clustering at opposite nuclear poles. Though considered to be typical for large cereal genomes, observations of Rabl configuration are based mostly on nuclei from meristematic tissues. We explored interphase chromosome organization in different tissues of developing barley grains and will show that Rabl chromosome organization is not a general rule in barley and it diminishes with the increasing nuclear DNA content and seed age. Furthermore, we performed transcriptome profiling of different barley grain tissues that allowed determining roles of different biological processes and also chromatin regulatory pathways during this critical stage of development. In summary, all these facets of our barley chromatin research create a fruitful environment for future functional analyses of nuclear organization and epigenetic regulation of gene expression in this agriculturally important species.

The dynamics of chromatin changes during barley seed development

Jaw movements during mammalian chewing drive occlusion and food breakdown. As important as jaw movements are for chewing, soft tissues within the oral cavity are essential for handling the food bolus throughout the chewing sequence. For instance, tongue movements and deformations (1) position the food between the tooth rows, (2) help mix the bolus with saliva to initiate digestion and improve swallowability, and (3) transport the bolus to the oropharynx to initiate the swallow. Tongue movements and deformations must be coordinated with jaw movements to ensure chewing performance and efficiency as well as to avoid self-injury, and previous research shows that disruption of the sensory input from the tongue alters jaw movements during chewing in pigs. Even though jaw and tongue movements during mammalian chewing are investigated extensively, their coordination pattern(s) have received less attention. We present three different approaches to quantify the correlation between jaw movements (opening and closing, mediolateral deviation) and tongue movements (positional changes such as protraction-retraction) and deformation (length and width changes) during chewing in pigs. At the sequence level, cross-correlations are used to calculate the lag in time between tongue and jaw kinematics. Cross-correlation analyses can also be carried out at the cycle level, albeit with less statistical power. Finally, functional data analysis standardizes and resamples the data to test for jaw-tongue correlation at each time point, essentially testing bivariate correlation continuously throughout the chewing cycle. We discuss the benefits and limitations of each methodology to emphasize the impact of combining analytical tools.

Jaw-tongue coordination during chewing in Pigs

The nutritional decisions of herbivores are inextricably tied to the thermal environment they experience. This pertains not just to the total energy eaten, but also to the macronutrients from which they choose to get that energy, and to the plant secondary metabolites (PSMs) that complicate the decision. The relationship between thermal physiology and nutritional ecology runs deeper than simply adjusting food intake to meet changes in metabolic rate. I will present results on how temperature-dependent toxicity applies to marsupial folivores ingesting diets high in plant secondary metabolites. Ambient temperature may also influence the mixing of macronutrients to minimise heat generation, and when a plant toxin is included in the diet, these feeding decisions can be further complicated. The addition of a plant secondary metabolite removed the effect of temperature on macronutrient balancing, so it may be that ingesting enough protein to deal with the cost of plant secondary metabolite ingestion overrides the desire to minimise the obligatory thermogenesis of a higher protein diet in warm conditions. Field data collected on koalas fitted with radio collars with microphones will be considered to observe this phenoma in a wild setting. Intake patterns of koalas were indeed influenced by temperature and plant secondary metabolite concentrations of available trees resulting in altered daily and per meal food intake. Temperature can have considerable impact on nutrition, and warming ambient temperatures due to climate change are likely to result in a new challenges for marsupial folivores and other herbivores, particularly those ingesting PSM rich diets.

Temperature-dependent toxicity and macronutrient selection in folivorous marsupials

Nutrition is a complex process of matching multiple and changing nutrient needs to variable and uncertain nutrient supply. Many behavioural and physiological mechanisms evolved to meet this challenge have been identified. However, little is known about how nutritional behaviour and physiology interact to produce an integrated, adapted nutritional phenotype, and how these integrated phenotypes vary with evolutionary and ecological circumstances. In this talk I present a series of studies that have used a framework from nutritional ecology, called nutritional geometry, to examine these issues. Examples span highly controlled laboratory studies of insect to observational studies of primates in the wild. I end by showing how this approach has been used to develop a new understanding of the human obesity epidemic

Underline digital video library

A new dataset of three-dimensional models in prehistoric Japan

Age specific foraging success and importance of ecological knowledge in Pemba, Tanzania

The Cascading Climate Impacts social simulation: Future of Food

Investigation into the effect of temperature on social foraging in Corydoras aeneus

Genotypic Variation in Heat Tolerance in Aus Rice During the Flowering Stage

Modelling bite force in insects: comparison of different PCSA approaches with in vivo measurements

No Bones About It: Soft Tissue Dynamics during Mammalian Mastication

Integration across anatomy and physiology is the basis for understanding feeding behaviour in vertebrates

The dynamics of chromatin changes during barley seed development

Jaw-tongue coordination during chewing in Pigs

Temperature-dependent toxicity and macronutrient selection in folivorous marsupials

Towards an integrated understanding of nutritional phenotypes

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