Eishi Hirasaki

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Armando Marques-Guedes

UNL - New University of Lisbon

Andrew Heckert

Appalachian State University

Monica Daley

University of California, Irvine

Robson Cruz

Universidade da Integração Internacional da Lusofonia Afro-Brasileira (UNILAB)

Mark A Schmuckler

University of Toronto

Fotios Alexandros Karakostis

University Of Tuebingen

Mohamad Shohibuddin

Bogor Agricultural University, Indonesia

Igor Berkunsky

Universidad Nacional del Centro de la Provincia de Buenos Aires

Hendra Gunawan

Institut Pertanian Bogor (IPB)

Scott A. Williams

New York University

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Papers by Eishi Hirasaki

Variation of thoracolumbar vertebral morphology in anthropoid primates

American journal of physical anthropology, Feb 2, 2024

Skipping without and with hurdles in bipedal macaque: Global mechanics

Macaques trained to perform bipedally used running gaits across a wide range of speed. At higher ... more Macaques trained to perform bipedally used running gaits across a wide range of speed. At higher speeds they preferred unilateral skipping (galloping). The same asymmetric stepping pattern was used while hurdling across two low obstacles placed at the distance of a stride within our experimental track. In bipedal macaques during skipping, we expected a differential use of the trailing and leading legs. The present study investigated global properties of the effective and virtual leg, the ___location of the virtual pivot point (VPP), and the energetics of the center of mass (CoM), with the aim of clarifying the differential leg operation during skipping in bipedal macaques. Macaques skipping displayed minor double support and aerial phases during one stride. Asymmetric leg use indicated by differences in leg kinematics. Axial damping and tangential leg work did not influence the indifferent peak ground reaction forces and impulses, but resulted in a lift of the CoM during contact of the...

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Range of rotation of thoracolumbar vertebrae in Japanese macaques

The Anatomical Record

Supplementary Information

ZIP file containing the 3D bone segments, the model definitions, and the movie files generated by... more

Data from: Quadrupedal locomotor simulation: producing more realistic gaits using dual-objective optimisation

In evolutionary biomechanics it is often considered that gaits should evolve to minimise the ener... more In evolutionary biomechanics it is often considered that gaits should evolve to minimise the energetic cost of travelling a given distance. In gait simulation this goal often leads to convincing gait generation. However, as the musculoskeletal models used get increasingly sophisticated, it becomes apparent that such a single goal can lead to extremely unrealistic gait patterns. In this paper we explore the effects of requiring adequate lateral stability and show how this both increases energetic cost and the realism of the generated walking gait in a high biofidelity chimpanzee musculoskeletal model. We also explore the effects of changing the footfall sequences in the simulation so it mimics both the diagonal sequence walking gaits that primates typically use and also the lateral sequence walking gaits that are much more widespread among mammals. It is apparent that adding a lateral stability criterion has an important effect on the footfall phase relationship suggesting that lateral stability may be one of the key drivers behind the observed footfall sequences in quadrupedal gaits. The observation that single optimisation goals are no longer adequate for generating gait in current models has important implications for the use of biomimetic virtual robots to predict the locomotor patterns in fossil animals

On the arrangement of the interossei pedis in apes

Locomotor function of shoulder muscles of the Japanese macaque (<i>Macaca fuscata</i>)

歩行中の視線安定を維持する頭部運動と眼球運動

Erratum: Energetic costs of bipedal and quadrupedal walking in Japanese macaques (American Journal of Physical Anthropology (2004) 124 (248-256))

American Journal of Physical Anthropology, 2004

Mechanical analysis of the relationship between the walk sequence and the center of mass of the body using a robot simulating Japanese macaques quadrupedal walking

The Proceedings of Conference of Kanto Branch, 2021

Muscle Spindle Density of Lateral Rotators of the Thigh in Japanese Macaques and a Gibbon

Cells Tissues Organs, 2019

We examined the six small lateral rotators of the hip joint, which is one of the most flexible jo... more We examined the six small lateral rotators of the hip joint, which is one of the most flexible joints and allows kinematically complex motions of the hindlimb, to elucidate the functional differentiation among these muscles and to test the hypothesis that species-specific characteristics in hindlimb use during locomotion are reflected in the muscle spindle density and in other parameters of the deep small hip joint rotators. For these purposes, we estimated the number of muscle spindles of the superior gemellus muscle (SG), inferior gemellus muscle, quadratus femoris muscle, obturator internus muscle (OI), obturator externus muscle, and piriformis muscle in three Japanese macaques and a gibbon, using 30-µm-thick serial sections throughout each muscle length after azan staining. The numbers of muscle spindles per 10,000 muscle fibers were determined to compare inter-muscle variation. The spindle density was highest in the SG and lowest in the OI in the Japanese macaques, suggesting t...

20220 Simulation of Japanese Macaque Quadruped Locomotion by Phase Oscillator

The Proceedings of Conference of Kanto Branch, 2014

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The comparison of the vertical climbing in primates

Anthropological Science Journal of the Anthropological Society of Nippon, Mar 15, 2000

Effects of Training on Bipedal Locomotion In Japanese Macaques-From the Viewpoint of Kinematics and Plantar Pressure Distribution

IEIC Technical Report ( …, 2006

Abstract;The locomotor characteristics of human walking are considered essential to efficient bip... more

Diagonal‐couplet gaits on discontinuous supports in Japanese macaques and implications for the adaptive significance of the diagonal‐sequence, diagonal‐couplet gait of primates

American Journal of Biological Anthropology

ObjectivesDiagonal‐sequence, diagonal‐couplet (DSDC) gaits have been proposed as an adaptation to... more ObjectivesDiagonal‐sequence, diagonal‐couplet (DSDC) gaits have been proposed as an adaptation to travel on discontinuously arranged arboreal branches. Only a few studies have examined primate gait adjustment to support discontinuity. We analyzed the gaits of Japanese macaques walking on the “ground” and two discontinuous conditions, “circle” and “point,” to better understand the advantages of DSDC gaits on discontinuous supports.Materials and MethodsSeventy‐eight vertical posts, each with a circular upper surface, were arranged in four rows at a spacing of 200 mm. The diameter of the circular upper surface was 150 mm (“circle condition”) or 50 mm (“point condition”). We calculated the limb phase, duty factor, and time interval from hindlimb touchdown to ipsilateral forelimb liftoff. The supports the fore‐ and hindlimbs landed on during walking were identified in the circle and point condition.ResultsThe macaques predominantly used DSDC gaits in the ground and circle conditions and ...

Morphological significance of the medial brachial cutaneous nerve: An anatomical study of the brachial plexus in primates

Primates

Coordination of trunk motion during bipedal walking in the frontal plane: A comparison between Homo sapiens, Macaca fuscata, and an exploratory study on a gibbon

American Journal of Biological Anthropology

ObjectivesIn human walking, the pelvis lists toward the swing side during the support phase while... more ObjectivesIn human walking, the pelvis lists toward the swing side during the support phase while the thorax lists toward the stance side. In contrast, during bipedal walking in chimpanzees, both the pelvis and thorax list toward the stance side during the support phase, making their body mass oscillation larger than that in humans. However, aside from a few reports on chimpanzees and macaques, studies on the relationship between trunk movements and step width during bipedal walking in nonhuman primates are limited.Materials and MethodsWe collected three‐dimensional trunk kinematic data during bipedal walking in five humans and five Macaca fuscata. While walking, the positions of cluster markers, which defined trunk segments, were recorded by multiple video cameras. Segmental xyz coordinates were digitized, and frontal rotations and translations were calculated using motion analysis software.ResultsThe kinematic approximation of the safety ratio, which is the center of mass motion r...

Producing non-steady-state gaits (starting, stopping, and turning) in a biologically realistic quadrupedal simulation

Frontiers in Ecology and Evolution

Multibody dynamic analysis (MDA) has become part of the standard toolkit used to reconstruct the ... more Multibody dynamic analysis (MDA) has become part of the standard toolkit used to reconstruct the biomechanics of extinct animals. However, its use is currently almost exclusively limited to steady state activities such as walking and running at constant velocity. If we want to reconstruct the full range of activities that a given morphology can achieve then we must be able to reconstruct non-steady-state activities such as starting, stopping, and turning. In this paper we demonstrate how we can borrow techniques from the robotics literature to produce gait controllers that allow us to generate non-steady-state gaits in a biologically realistic quadrupedal simulation of a chimpanzee. We use a novel proportional-derivative (PD) reach controller that can accommodate both the non-linear contraction dynamics of Hill-type muscles and the large numbers of both single-joint and two-joint muscles to allow us to define the trajectory of the distal limb segment. With defined autopodial traject...

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Relationship between the lumbosacral plexus deviation and 12th rib length in Japanese macaques (Macaca fuscata)

Anatomical Science International

The relationship between the lumbosacral plexus (LSP) origin and the 12th rib length was recently... more The relationship between the lumbosacral plexus (LSP) origin and the 12th rib length was recently determined in humans; cranial and caudal deviations of the plexus origin are related to shortening and elongation of the 12th rib, respectively. However, it remains unclear whether such anatomical correlations are also observed in non-human mammals. To address this issue, in the present study, we evaluated the LSP origin and the 12th rib length in Japanese macaques (Macaca fuscata). In typical cases, the femoral and obturator nerves were derived from both the 4th and 5th lumbar nerves, and the lumbosacral trunk was from the 5th to 7th lumbar nerves. Some of the LSPs exhibited a caudal deviation of their origins; the femoral and obturator nerves were also derived from the 6th lumbar nerve, in addition to the 4th and 5th lumbar nerves; the lumbosacral trunk lost the 5th lumbar nerve origin and arose from the 6th and 7th lumbar nerves. Individuals with the caudal deviation of LSP origin exhibited significant elongation of the 12th ribs, in comparison with individuals with the typical plexus. The present findings indicate that the caudal deviation of LSP origin was correlated to the 12th rib elongation in Japanese macaques, similar to humans. As a future studies, we need to clarify which mammalian groups exhibit such correlation between the deviation of the LSP origin and the lowest rib length, and further to provide evolutionary implications of this correlation.

Comparison of the soleus and plantaris muscles in humans and other primates: Macroscopic neuromuscular anatomy and evolutionary significance

The Anatomical Record

In humans, the soleus is more developed compared to other primates and has a unique architecture ... more In humans, the soleus is more developed compared to other primates and has a unique architecture composed of anterior bipennate and posterior unipennate parts, which are innervated by different nerve branches. The anterior part of the human soleus was proposed to be important for bipedalism, however, the phylogenetic process resulting in its acquisition remains unclear. Providing insights into this process, the anterior part of the soleus was suggested to be closely related to the plantaris based on the branching pattern of their nerve fascicles. To reveal the phylogeny of the soleus and plantaris in primates, the innervation patterns of the posterior crural muscles were compared among a wide range of species. From their branching pattern, posterior crural muscles could be classified into superficial and deep muscle groups. The anterior part of the soleus and plantaris both belonged to the deep muscle group. In all the examined specimens of ring‐tailed lemurs and chimpanzees, as wel...

Variation of thoracolumbar vertebral morphology in anthropoid primates

American journal of physical anthropology, Feb 2, 2024

Skipping without and with hurdles in bipedal macaque: Global mechanics

Download

Range of rotation of thoracolumbar vertebrae in Japanese macaques

The Anatomical Record

Supplementary Information

ZIP file containing the 3D bone segments, the model definitions, and the movie files generated by... more

Data from: Quadrupedal locomotor simulation: producing more realistic gaits using dual-objective optimisation

On the arrangement of the interossei pedis in apes

Locomotor function of shoulder muscles of the Japanese macaque (<i>Macaca fuscata</i>)

歩行中の視線安定を維持する頭部運動と眼球運動

Erratum: Energetic costs of bipedal and quadrupedal walking in Japanese macaques (American Journal of Physical Anthropology (2004) 124 (248-256))

American Journal of Physical Anthropology, 2004

Mechanical analysis of the relationship between the walk sequence and the center of mass of the body using a robot simulating Japanese macaques quadrupedal walking

The Proceedings of Conference of Kanto Branch, 2021

Muscle Spindle Density of Lateral Rotators of the Thigh in Japanese Macaques and a Gibbon

Cells Tissues Organs, 2019

20220 Simulation of Japanese Macaque Quadruped Locomotion by Phase Oscillator

The Proceedings of Conference of Kanto Branch, 2014

Download

The comparison of the vertical climbing in primates

Anthropological Science Journal of the Anthropological Society of Nippon, Mar 15, 2000

Effects of Training on Bipedal Locomotion In Japanese Macaques-From the Viewpoint of Kinematics and Plantar Pressure Distribution

IEIC Technical Report ( …, 2006

Abstract;The locomotor characteristics of human walking are considered essential to efficient bip... more

Diagonal‐couplet gaits on discontinuous supports in Japanese macaques and implications for the adaptive significance of the diagonal‐sequence, diagonal‐couplet gait of primates

American Journal of Biological Anthropology

Morphological significance of the medial brachial cutaneous nerve: An anatomical study of the brachial plexus in primates

Primates

Coordination of trunk motion during bipedal walking in the frontal plane: A comparison between Homo sapiens, Macaca fuscata, and an exploratory study on a gibbon

American Journal of Biological Anthropology

Producing non-steady-state gaits (starting, stopping, and turning) in a biologically realistic quadrupedal simulation

Frontiers in Ecology and Evolution

Download

Relationship between the lumbosacral plexus deviation and 12th rib length in Japanese macaques (Macaca fuscata)

Anatomical Science International

Comparison of the soleus and plantaris muscles in humans and other primates: Macroscopic neuromuscular anatomy and evolutionary significance

The Anatomical Record

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