Michael C Granatosky- Doctor of Philosophy
- Professor (Assistant) at New York Institute of Technology
Michael C Granatosky
- Doctor of Philosophy
- Professor (Assistant) at New York Institute of Technology
About
130
Publications
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Introduction
Current institution
Additional affiliations
January 2008 - August 2011
August 2011 - March 2016
Publications
Publications (130)
Access to high‐quality outreach programs is crucial for preparing students for STEM careers, yet traditional classrooms often lack diverse, hands‐on learning opportunities, particularly in anatomy and evolutionary biology. We present "Are You Stronger Than a Lemur?"—an interactive STEM activity that introduces K‐12 students to fundamental concepts...
Suspensory locomotion differs significantly from upright quadrupedal locomotion in mammals. Nevertheless, we know little concerning joint kinematics of suspensory movement. Here, we report three‐dimensional kinematic data during locomotion in brown‐throated three‐toed sloths ( Bradypus variegatus ). Individuals were recorded with four calibrated hi...
Powerful digital grasping is essential for primates navigating arboreal environments and is often regarded as a defining characteristic of the order. However, in vivo data on primate grip strength are limited. In this study, we collected grasping data from the hands and feet of eleven strepsirrhine species to assess how ecomorphological variables—s...
It is thought that the magnitude of center of mass (COM) oscillations can affect stability and locomotor costs in arboreal animals. Previous studies have suggested that minimizing collisional losses and maximizing pendular energy exchange are effective mechanisms to reduce muscular input and energy expenditure during terrestrial locomotion. However...
The gait characteristics associated with arboreal locomotion have been frequently discussed in the context of primate evolution, wherein they present as a trio of distinctive features: a diagonal-sequence, diagonal-couplet gait pattern, a protracted arm at forelimb touchdown, and a hindlimb-biased weight support pattern. The same locomotor characte...
Gross anatomy is a crucial course in medical school; it sets the foundation for future coursework and is highly valued by clinicians. While both medical students and faculty recognize the importance of pre‐medical school anatomy experience, few medical schools require it as a prerequisite. Consequently, medical school gross anatomy courses have a d...
New World porcupines (Erethizontinae) originated in South America and dispersed into North America as part of the Great American Biotic Interchange (GABI) 3-4 million years ago. Extant prehensile-tailed porcupines (Coendou) today live in tropical forests of Central and South America. In contrast, North American porcupines (Erethizon dorsatum) are t...
Synopsis
Center of mass (COM) mechanics, often used as an energetic proxy during locomotion, has primarily focused on level movement and hardly explores climbing scenarios. This study examines three-dimensional COM movements across five phylogenetically distinct species to test theoretical expectations of climbing costs, explore how interspecific v...
Climbing animals theoretically need to optimize the energetic costs of vertical climbing while also maintaining stability. Many modifications to climbing behaviors have been proposed as methods of satisfying these criteria, focusing on controlling the center of mass (COM) during ascent. However, the link between COM movements and metabolic energy c...
Climbing represents a critical behavior in the context of primate evolution. However, anatomically modern human populations are considered ill-suited for climbing. This adaptation can be attributed to the evolution of striding bipedalism, redirecting anatomical traits away from efficient climbing. Although prior studies have speculated on the kinet...
Occupation of arboreal habitats poses myriad locomotor challenges, driving both anatomical and behavioural innovations across various tetrapod lineages. Here, we report and biomechanically assess a novel, beak-driven locomotor mode-'beakiation'-by which parrots advance along the underside of narrow arboreal substrates. Using high-speed videography...
Analysis of muscle architecture, traditionally conducted via gross dissection, has been used to evaluate adaptive relationships between anatomical form and behavioral function. However, gross dissection cannot preserve three‐dimensional relationships between myological structures for analysis. To analyze such data, we employ diffusible, iodine‐base...
Mustn1, a gene expressed exclusively in the musculoskeletal system, was shown in previous in vitro studies to be a key regulator of myogenic differentiation and myofusion. Other studies also showed Mustn1 expression associated with skeletal muscle development and hypertrophy. However, its specific role in skeletal muscle function remains unclear. T...
Prokinesis, a mode of avian cranial kinesis involving motion between the neurocranium and upper beak, has long been investigated in biomechanical analyses of avian feeding and drinking. However, the modern avian beak is also used in a number of non-feeding functions. Here we investigate the dual function of prokinesis in the feeding and locomotor s...
Dynamic changes in jaw movements and bite forces depend on muscle architectural and neural factors that have rarely been compared within the same muscle. Here we investigate how regional muscle architecture dynamics—fascicle rotation, shortening, lengthening and architectural gear ratio (AGR)—vary during chewing across a functionally heterogeneous...
Across tetrapods, the proportional lengths of the manual and pedal phalanges are highly constrained, following a generalized blueprint of shortening in a proximodistal gradient. Despite this, several lineages of both mammals (e.g. sloths, bats and colugos) and birds (e.g. raptors, parrots and woodpeckers) have broken this pattern, shortening the pr...
Simple Summary
Parrots (Order: Psittaciformes) are an ancient arboreal lineage with a long history as companion animals for humans. Since at least the 1960s, released parrots have become established in non-native ranges globally. The method of their introduction is almost certainly a direct result of the pet trade through either accidental or inten...
Birds encompass vast ecomorphological diversity and practise numerous distinct locomotor modes. One oft-cited feature seen in climbing birds is an increase in tail ‘stiffness’, yet it remains unclear to what extent these feathers are altered, and the specific mechanism by which differences in functional performance are attained. We collected a broa...
At what inclination does climbing begin? In this paper, we investigate the transition from walking to climbing in two species of parrot (Agapornis roseicollis and Nymphicus hollandicus) that are known to incorporate both their tail and their craniocer-vical system into the gait cycle during vertical climbing. Locomotor behaviors ranging in inclinat...
Simple Summary
Brachiation is a form of suspensory (i.e., meaning the animal hangs below branches) locomotion in which only the forelimbs are used for weight support and propulsion. Brachiation has only ever evolved in Primates, and the living hominoids (i.e., apes) are considered specialized brachiating species. Odd among the apes are humans who h...
Understanding the locomotor characteristics of early diverging ground-walking chameleons (members of the genera Brookesia, Rhampholeon, Palleon, and Rieppeleon) can help to explain how their unique morphology is adapted to fit their environment and mode of life. However, nearly all quantitative studies of chameleon locomotion thus far have focused...
Modern tree sloths are one of few mammalian taxa for which quadrupedal suspension is obligatory. Sloth limb musculature is specialized for slow velocity, large force contractions that stabilize their body below branches and conserves energy during locomotion. However, it is unknown if two and three-toed sloths converge in their use of limb biomecha...
The Primates have a long evolutionary history associated with the arboreal milieu. Field and laboratory investigations of primate locomotion have traditionally been limited to observations of adult animals. This chapter discusses several examples of how studies of primate locomotor ontogeny have contributed to our understanding of primate biology a...
Despite the high mechanical demands associated with climbing, the ability to ascend vertically has evolved independently in most major animal lineages. However, little is known about the kinetics, mechanical energy profiles, or spatiotemporal gait characteristics of this locomotor mode. In this study, we explore the dynamics of horizontal locomotio...
Living sloths exhibit numerous anatomical specializations towards inverted quadrupedalism, however, previous studies have noted a more varied locomotor repertoire than previously anticipated. In this study, we present spatiotemporal gait characteristics and triaxial kinetic data from the brown-throated three-toed sloth (Bradypus variegatus) across...
Echolocation is the primary sense used by most bats to navigate their environment. However, the influence of echolocating behaviors upon the morphology of the auditory apparatus remains largely uninvestigated. While it is known that middle ear ossicle size scales positively with body mass across mammals, and that peak call frequency scales negative...
Sloths are among the most specialized arboreal species and have evolved a suite of anatomical features that support suspensory behaviors. While sloths generally show a reduction in skeletal muscle mass, the digital flexor musculature (i.e., the muscles associated with grip strength) remains relatively large. It may therefore be inferred that grip s...
The subfossil lemurs of Madagascar have been discussed and studied in great detail due to their remarkable preservation, phylogenetic history, and locomotor convergence with a number of extant taxa. This chapter highlights these discussions with particular focus on the variation in pedal morphology observed across the three extinct families of subf...
The ability to securely grasp substrates of variable diameter is critical to arboreal animals. Arboreal specialists have emerged across several vertebrate lineages – including mammals, lizards, and amphibians – and several attempts have been made to quantify their grasping performance, by measuring either gripping (i.e., forces generated about an o...
Bite force represents a critical measure of an animal's feeding capabilities and has been analyzed in the context of ecology and body size in numerous vertebrate lineages. Among birds, bite force potential has been comprehensively quantified in finches; however, no in vivo data have been reported within parrots (order: Psittaciformes), and an anato...
Simple Summary
Positional behaviors comprise the entirety of animals’ locomotion and posture. Often, these positional behaviors are paired with information about sußbstrate characteristics (e.g., orientation, diameter, texture, height) and frequency to gain an ecological perspective of when and why an animal utilizes a particular behavior. Thus far...
Suction feeding in fishes is characterized by rapid cranial movements, but extant lungfishes (Sarcopterygii: Dipnoi) exhibit a reduced number and mobility of cranial bones relative to actinopterygian fishes. Despite fusion of cranial elements, lungfishes are proficient at suction feeding, though the impacts of novel cranial morphology and reduced c...
The morphology of the mammalian middle ear – including the size, shape, and stiffness of individual ossicles – controls their vibrational response to sound and, as such, is closely related to an animal's auditory capabilities. While the relationship between middle ear morphology and hearing frequency has been explored in living carnivorans, the siz...
The biomechanical demands of arboreal locomotion are generally thought to necessitate specialized kinetic and kinematic gait characteristics. While such data has been widely collected across arboreal quadrupeds, no study has yet explored how arboreal substrates influence the locomotor behavior of birds. Parrots – an ancient arboreal lineage that ex...
Few realized the extent of disruption that the Covid‐19 global pandemic would impose upon higher anatomical education. While many institutions were obliged to adopt a fully‐remote online model, the New York Institute of Technology College of Osteopathic Medicine strove to develop a curriculum that would allow medical students to receive an in‐perso...
The locomotor behaviors of treeshrews are often reported as scurrying "squirrel-like" movements. As such, treeshrews have received little attention beyond passing remarks in regard to primate locomotor evolution. However, scandentians vary considerably in habitat and substrate use, thus categorizing all treeshrew locomotion based on data collected...
Evolutionary analyses of joint kinematics and muscle mechanics suggest that, during cyclic behaviors, tetrapod feeding systems are optimized for precise application of forces over small displacements during chewing while locomotor systems are more optimized for large and rapid joint excursions during walking and running. If this hypothesis is corre...
No vertebrate, living or extinct, is known to have possessed an odd number of limbs. Despite this ‘forbidden phenotype’, gaits that use odd numbers of limbs (e.g. tripedalism or pentapedalism) have evolved in both avian and mammalian lineages. Tripedal locomotion is commonly employed by parrots during climbing, who use their beaks as an additional...
A key characteristic of primate above-branch arboreal locomotion is hindlimb-biased weight support, subverting the typical mammalian condition in which the majority of the body weight is supported by the forelimb. This shift is thought to reflect an adaptation toward the arboreal niches exploited by early primates. However, above-branch quadrupedal...
The difficulty of quantifying asymmetrical limb movements, compared with symmetrical gaits, has resulted in a dearth of information concerning the mechanics and adaptive benefits of these locomotor patterns. Further, no study has explored the evolutionary history of asymmetrical gaits using phylogenetic comparative techniques. Most foundational wor...
Speed regulation in animals involves stride frequency and stride length. While the relationship between these variables has been well documented, it remains unresolved whether animals primarily modify stride frequency or stride length to increase speed. In this study, we explored the interrelationships between these three variables across a sample...
During the last decade, biomechanical and kinematic studies have suggested that a belly-dragging gait may have represented a critical locomotor stage during tetrapod evolution. This form of locomotion is hypothesized to facilitate animals to move on land with relatively weaker pectoral muscles. The Indonesian blue-tongued skink (Tiliqua gigas) is k...
While red-backed salamanders (Plethodon cinereus) are most often observed in terrestrial forested areas, several studies report arboreal substrate use and climbing behavior. However, salamanders do not have any of the anatomical features commonly observed in specialized climbing species (e.g., claws, setae, suction cups). Instead, salamanders cling...
In terrestrial quadrupeds where the forelimbs are habitually used to push against the substrate, the ulna is subjected to cranial bending and develops a caudal curvature. During arboreal locomotion, the forelimbs are habitually used to pull on the substrate during climbing and clinging, and the ulna responds to this bending load by developing a cra...
Vertebrates employ an impressive range of strategies for coordinating their limb movements while walking. Although this gait variation has been quantified and hypotheses for its origins tested in select tetrapod lineages, a comprehensive understanding of gait evolution in a macroevolutionary context is currently lacking. We used freely available in...
Studies of positional behavior, gait, and habitat use are important for understanding how animals adapt to the challenges of their environment. In turn, this information is useful for advancing research on primate morphology, life history, and ecology. Data on eco-mechanical variables can be used to develop concrete conservation and management plan...
Arboreal mammals have evolved a range of biomechanical adaptations that allow them to
navigate trees effectively. One such feature that has received considerable attention is the importance of vision that helps arboreal animals assess gap distances, assure proper foot placement, and inspect potential risks. While there is considerable debate about...
Objectives:
The competing functional demands of diarthrodial joints, permitting mobility while retaining enough stability to transmit forces across the joint, have been linked with the shape and size of the joint's articular surfaces. A clear understanding of the relationship between joint morphology and joint movement potential is important for r...
Urinary C-peptide (UCP) is a biomarker for insulin that can be used as a non-invasive physiological measure of energy balance. Previous research has validated the use of UCP to quantify energy balance in catarrhines; however, there have been no such studies in platyrrhines. Validation is necessary in this lineage of primates as divergent evolution...
Quadrupedal animal locomotion is energetically costly. We explore two forms of mechanical work that may be relevant in imposing these physiological demands. Limb work, due to the forces and velocities between the stance foot and the centre of mass, could theoretically be zero given vertical limb forces and horizontal centre of mass path. To prevent...
Tetrapod musculoskeletal diversity is usually studied separately in feeding and locomotor systems. However, direct comparisons between these systems promise important insight into how natural selection deploys the same basic musculoskeletal toolkit—connective tissues, bones, nerves, and skeletal muscle—to meet the differing performance criteria of...
Gaze-tracking techniques have advanced our understanding of visual attention and decision making during walking and athletic events, but little is known about how vision influences behavior during running over common, natural obstacles. This study tested hypotheses about whether runners regularly collect visual information and pre-plan obstacle cle...
Some varanid lizards show a prominent and highly distinctive lateral calcaneal process. It has been posited that this structure serves as a lateral “heel” to increase the moment arm for m. peroneus longus, allowing it to function as a powerful propulsive muscle. However, to confirm that m. peroneus longus serves this function requires electromyogra...
Jaw-muscle architecture is a key determinant of jaw movements and bite force. While static length-force and force-velocity relationships are well documented in mammals, architecture dynamics of the chewing muscles and their impact on muscle performance are largely unknown. We provide novel data on how fiber architecture of the superficial anterior...
Comparative analyses of locomotion in tetrapods reveal two patterns of stride cycle variability. Tachymetabolic tetrapods (birds and mammals) have lower inter-cycle variation in stride duration than bradymetabolic tetrapods (amphibians, lizards, turtles, and crocodilians). This pattern has been linked to the fact that birds and mammals share enlarg...
Tetrapod musculoskeletal diversity is usually studied separately in feeding and locomotor systems. However, comparisons between these systems promise important insight into how natural selection deploys the same basic musculoskeletal toolkit-connective tissues, bones, nerves and skeletal muscle-to meet the differing performance criteria of feeding...
Arm-swinging is a locomotor mode observed only in primates, in which the hindlimbs no longer have a weight bearing function and the forelimbs must propel the body forward and support the entirety of the animal's mass. It has been suggested that the evolution of arm-swinging was preceded by a shift to inverted quadrupedal walking for purposes of fee...
Greyhound racing is a competitive, organized sport in which bets are placed as greyhounds run around a track (Baker 1996; Thompson 2003). There are two forms of dog racing, which include track racing and coursing. Track racing utilizes an artificial lure that travels along a rail ahead of the dogs until the hounds cross the finish line. In contrast...
Speed-related gait transitions occur in many animals, but it remains unclear what factors trigger gait changes. While the most widely accepted function of gait transitions is that they reduce locomotor costs, there is no obvious metabolic trigger signalling animals when to switch gaits. An alternative approach suggests that gait transitions serve t...
During quadrupedal walking, most primates utilize diagonal sequence diagonal couplet gaits, large limb excursions, and hindlimb-biased limb-loading. These gait characteristics are thought to be basal to the Order, but the selective pressure underlying these gait changes remains unknown. Some researchers have examined these characteristics during ve...
Objectives
In this study, we explore whether ground reaction forces recorded during horizontal walking co‐vary with the shape of the long bones of the forelimb in strepsirrhines. To do so, we quantify (1) the shape of the shaft and articular surfaces of each long bone of the forelimb, (2) the peak vertical, mediolateral, and horizontal ground react...
Locomotor diversity has meant many different things depending on the subject area or investigator. While no concrete definition of locomotor diversity is currently available, this has not stopped researchers from making a number of assertions about the underlying mechanisms that determine whether a species will have high or low locomotor diversity....
Over the last decade, we have learned much about the anatomy, evolutionary history, and biomechanics of the extant sloths. However, most of this work has involved studying sloths in controlled conditions, and few studies have explored how these animals are behaving in a naturalistic setting. In this study, we integrate positional activities in natu...
Adaptations for flight have greatly modified the forelimbs and hindlimbs of bats compared to other mammals so that terrestrial and/or above branch quadrupedal locomotion is awkward and unusual for most species. However, suspensory quadrupedal gaits are quite common for bats, but little is known about this type of movement and no data are available...
During quadrupedal walking in most animals, the forelimbs play a net braking role while the hindlimbs are net propulsive. However, the mechanism by which this differentiation occurs remains unclear. Here we test two models to explain this pattern using primates and felines: (1) the Horizontal Strut Effect (in which limbs are modeled as independent...
Objectives:
Pygathrix is an understudied Asian colobine unusual among the Old World monkeys for its use of arm-swinging. Little data exists on the anatomy and mechanics of brachiation in this genus. Here, we consider this colobine to gain insight into the parallel evolution of suspensory behavior in primates.
Materials and methods:
This study co...
Vertical climbing is an essential behavior for arboreal animals, yet limb mechanics during climbing are poorly understood and rarely compared to those observed during horizontal walking. Primates commonly engage in both arboreal walking and vertical climbing, and this makes them an ideal taxa in which to compare these locomotor forms. Additionally,...
The evolution of primates is intimately linked to their initial invasion of an arboreal environment. However, moving and foraging in this milieu creates significant mechanical challenges related to the presence of substrates differing in their size and orientation. It is widely assumed that primates are behaviorally and anatomically adapted to move...
The living sloths are the most suspensory of all extant mammals, and therefore represent ideal models for investigating the effects that suspensory behaviours have on bone and joint morphology. While the anatomy and kinematics of sloths are well known, no research has reported kinetic patterns of sloth locomotion. This study examines peak force pat...
Gait mechanics in habitual quadrupedal primates has been explored thoroughly. However, little is known about the movements of quadrupedal primates that regularly engage in other, more specialized, forms of locomotion (e.g., suspensory or leaping). It is unclear whether the patterns of quadrupedal locomotion in these anatomically specialized species...
Questions
Question (1)
Hello,
I am trying to find some papers that explore gait transitions and energetics on declines. Essentially, I am trying to figure out whether the preferred transition speed and energetically optimal transition would be the same or different during downhill walking to running. I am having a lot of trouble finding any references. The closest paper I found was: The cost of walking downhill: is the preferred gait energetically optimal?
Any help would be greatly appreciated,
Michael
