Evidence map›Paper›PMID 41168292›Full record

ArticleScientific reports2025

Gorilla knuckle-walking mechanics suggest independent evolution in African great apes.

Akimasa Ito, Masayuki Tanaka, Nobuaki Yoshida, Naomichi Ogihara

Abstract read
In one paragraph

Article in Scientific reports, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

4 authors.

Akimasa ItoLaboratory of Human Evolutionary Biomechanics, Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan. akimasa-ito@g.ecc.u-tokyo.ac.jp.
Masayuki TanakaCenter for Research and Education of Wildlife, Kyoto City Zoo, Kyoto, 606-8333, Japan.
Nobuaki YoshidaAdvanced Science, Technology & Management Research Institute of Kyoto, Kyoto, 600-8813, Japan.
Naomichi OgiharaLaboratory of Human Evolutionary Biomechanics, Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan. ogihara@bs.s.u-tokyo.ac.jp.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Gorillas and chimpanzees both use knuckle-walking (KW). Whether this behavior is a homologous trait inherited from their last common ancestor or the result of convergent evolution remains debated. This study investigated the biomechanics of gorilla KW by measuring ground reaction forces (GRFs) and comparing them with previously reported chimpanzee data. GRFs were recorded using two in-series force plates embedded in a horizontal beam in the outdoor enclosure of Kyoto City Zoo. Three adult gorillas voluntarily performed KW during normal activity, and 90 steady-state trials were analyzed. The results revealed interspecific differences: chimpanzees exhibited greater peak vertical GRFs in the hindlimbs, approximately 1.5 times those in the forelimbs, suggesting greater hindlimb weight support. In contrast, gorillas showed comparable peak GRFs in both limbs, with slightly higher values in the hindlimbs, indicating a more balanced weight distribution. Moreover, two individuals showed out-of-phase fluctuations in gravitational and kinetic energy of the center of mass, indicating an inverted pendulum mechanism and relatively efficient energy recovery. The distinct GRF patterns and apparent mechanical efficiency suggest that gorilla KW differs biomechanically from that of chimpanzees. These findings appear to be consistent with the hypothesis that KW in gorillas and chimpanzees evolved independently, which may suggest convergent evolution rather than shared ancestry.

Indexed as

Biological EvolutionGorilla gorillaWalkingAnimalsBiomechanical PhenomenaFemaleHindlimbMalePan troglodytes

Identifiers

PMID41168292
PMCPMC12575676

What OpenQuestion holds

Textmetadata
LicenceCC BY-NC-ND
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.