Great ape thorax and shoulder configuration—An adaptation for arboreality or knuckle-walking?

Thompson, Nathan E.; Rubinstein, Danielle; Larson, Susan G.

doi:10.1016/j.jhevol.2018.09.005

Cited by 13 publications

(14 citation statements)

References 59 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…All kinematic data were recorded using a four-camera Xcitex motion capture system (Xcitex, Inc., Woburn, MA, USA) recording at 150 Hz, and largely followed methodologies published elsewhere (O'Neill et al, 2015;Thompson et al, 2015Thompson et al, , 2018b. Six trials were collected for each subject, for a total of 12 trials for each species.…”

Section: Kinematic Methodsmentioning

confidence: 99%

“…More recently, the digital-level differences in force and pressure magnitude have also been documented via pressure pad studies (Matarazzo, 2013;Wunderlich and Jungers, 2009). Across the entire hand, the 3-D forces associated with knuckle-walking have been well documented (Demes et al, 1994;Kimura, 1985;Kimura et al, 1979;Li et al, 2004;Pontzer et al, 2014;Sockol et al, 2007;Thompson et al, 2018b). Yet, accurate kinematic data have remained scarce.…”

Section: Introductionmentioning

confidence: 96%

See 1 more Smart Citation

The biomechanics of knuckle-walking: 3-D kinematics of the chimpanzee and macaque wrist, hand and fingers

Thompson

2020

Journal of Experimental Biology

Self Cite

View full text Add to dashboard Cite

The origin and evolution of knuckle-walking has long been a key focus in understanding African ape, including human, origins. Yet, despite numerous studies documenting morphological characteristics potentially associated with knuckle-walking, little quantitative three-dimensional (3-D) data exist of forelimb motion during knuckle-walking. Nor do any comparative 3-D data exist for hand postures used during quadrupedalism in monkeys. This lack of data has limited the testability of proposed adaptations for knuckle-walking in African apes. This study presents the first 3-D kinematic data of the wrist, hand and metacarpophalangeal joints during knuckle-walking in chimpanzees and in macaques using digitigrade and palmigrade hand postures. These results clarify the unique characteristics of, and commonalities between, knuckle-walking and digitigrady/palmigrady in multiple planes of motion. Notably, chimpanzees utilized more wrist ulnar deviation than any macaque hand posture. Maximum extension of the chimpanzee wrist was slight (5–20 deg) and generally overlapped with macaque digitigrady. Metacarpophalangeal joint motion displayed distinct differences between digits in both species, likely related to the timing of force application. These data also reveal that maximum metacarpophalangeal extension angles during knuckle-walking (26–59 deg) were generally higher than previously considered. In macaques, maximum metacarpophalangeal extension during digitigrady and palmigrady overlapped for most digits, highlighting additional complexity in the interpretation of skeletal features that may be related to limiting metacarpophalangeal motion. Most importantly, however, these new 3-D data serve as a fundamental dataset with which evaluation of proposed musculoskeletal adaptations for knuckle-walking can be tested.

show abstract

Section: Kinematic Methodsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 96%

The biomechanics of knuckle-walking: 3-D kinematics of the chimpanzee and macaque wrist, hand and fingers

Thompson

2020

Journal of Experimental Biology

Self Cite

View full text Add to dashboard Cite

show abstract

“…However, this limitation of glenohumeral joint is artificial and does not aim to reflect arm-raising kinematics of humans or gorillas during natural movement sequences. Kinematic studies of various arboreal locomotion have shown that shoulder kinematics are highly threedimensional and thereby emphasized the great shoulder flexibility in hominoids (Isler, 2002(Isler, , 2005Thompson et al, 2018). Since moment arm is dependent on joint position, we can expect moment arm results to differ when glenohumeral elevation in other planes and long-axis rotation are included into the analysis.…”

Section: Study Limitationsmentioning

confidence: 99%

Exploring the functional morphology of the Gorilla shoulder through musculoskeletal modelling

et al. 2021

View full text Add to dashboard Cite

Musculoskeletal computer models allow us to quantitatively relate morphological features to biomechanical performance. In non‐human apes, certain morphological features have long been linked to greater arm abduction potential and increased arm‐raising performance, compared to humans. Here, we present the first musculoskeletal model of a western lowland gorilla shoulder to test some of these long‐standing proposals. Estimates of moment arms and moments of the glenohumeral abductors (deltoid, supraspinatus and infraspinatus muscles) over arm abduction were conducted for the gorilla model and a previously published human shoulder model. Contrary to previous assumptions, we found that overall glenohumeral abduction potential is similar between Gorilla and Homo. However, gorillas differ by maintaining high abduction moment capacity with the arm raised above horizontal. This difference is linked to a disparity in soft tissue properties, indicating that scapular morphological features like a cranially oriented scapular spine and glenoid do not enhance the abductor function of the gorilla glenohumeral muscles. A functional enhancement due to differences in skeletal morphology was only demonstrated in the gorilla supraspinatus muscle. Contrary to earlier ideas linking a more obliquely oriented scapular spine to greater supraspinatus leverage, our results suggest that increased lateral projection of the greater tubercle of the humerus accounts for the greater biomechanical performance in Gorilla. This study enhances our understanding of the evolution of gorilla locomotion, as well as providing greater insight into the general interaction between anatomy, function and locomotor biomechanics.

show abstract

“…In surveying the presence or absence of an impact transient force, we utilize a fairly simple criteria, but one which is often implicitly used (e.g., Henriksen et al, 2006; Lieberman et al, 2010; Thompson, Rubinstein, & Larson, 2018; Whittle, 1999). An impact transient force is present when there exists a local maximum (and subsequently minimum) in the vertical ground reaction force early in stance phase prior to the maximum force (or near‐maximum in the case of M‐shaped ground reaction forces).…”

Section: Evolutionary History and Comparative Biomechanicsmentioning

confidence: 99%

The menisci are not shock absorbers: A biomechanical and comparative perspective

Gecelter

Ilyaguyeva

Thompson

2021

The Anatomical Record

Self Cite

View full text Add to dashboard Cite

The lateral and medial menisci are fibrocartilaginous structures in the knee that play a crucial role in normal knee biomechanics. However, one commonly cited role of the menisci is that they function as “shock absorbers.” Here we provide a critique of this notion, drawing upon a review of comparative anatomical and biomechanical data from humans and other tetrapods. We first review those commonly, and often exclusively, cited studies in support of a shock absorption function and show that evidence for a shock absorptive function is dubious. We then review the evolutionary and comparative evidence to show that (1) the human menisci are unremarkable in morphology compared with most other tetrapods, and (2) “shock” during locomotion is uncommon, with humans standing out as one of the only tetrapods that regularly experiences high levels of shock during locomotion. A shock‐absorption function does not explain the origin of menisci, nor are human menisci specialized in any way that would explain a unique shock‐absorbing function during human gait. Finally, we show that (3) the material properties of menisci are distinctly poorly suited for energy dissipation and that (4) estimations of meniscal energy absorption based on published data are negligible, both in their absolute amount and in comparison to other well‐accepted structures which mitigate shock during locomotion. The menisci are evolutionarily ancient structures crucial for joint congruity, load distribution, and stress reduction, among a number of other functions. However, the menisci are not meaningful shock absorbers, neither in tetrapods broadly, nor in humans.

show abstract

Great ape thorax and shoulder configuration—An adaptation for arboreality or knuckle-walking?

Cited by 13 publications

References 59 publications

The biomechanics of knuckle-walking: 3-D kinematics of the chimpanzee and macaque wrist, hand and fingers

The biomechanics of knuckle-walking: 3-D kinematics of the chimpanzee and macaque wrist, hand and fingers

Exploring the functional morphology of the Gorilla shoulder through musculoskeletal modelling

The menisci are not shock absorbers: A biomechanical and comparative perspective

Contact Info

Product

Resources

About