Body proportions and environmental adaptation in gorillas

Abstract

Objectives: Limb length and trunk proportions are determined in a large, taxonomically and environmentally diverse sample of gorillas and related to variation in locomotion, climate, altitude, and diet. Materials and methods:The sample includes 299 gorilla skeletons, 115 of which are infants and juveniles, distributed between western lowland (G. gorilla gorilla), low and high elevation grauer (G. beringei graueri), and Virunga mountain gorillas (G. b. beringei). Limb bone and vertebral column lengths scaled to body mass are compared between subgroups by age group.Results: All G. beringei have relatively short 3rd metapodials and manual proximal phalanges compared to G. gorilla, and this difference is apparent in infancy. All G. beringei also have shortened total limb lengths relative to either body mass or vertebral column length, although patterns of variation in individual skeletal elements are more complex, and infants do not display the same patterns as adults. Mountain gorillas have relatively long clavicles, present in infancy, and a relatively long thoracic (but not lumbosacral) vertebral column.Discussion: A variety of environmental factors likely contributed to observed patterns of morphological variation among extant gorillas. We interpret the short hand and foot bones of all G. beringei as genetic adaptations to greater terrestriality in the last common ancestor of G. beringei; variation in other limb lengths to climatic adaptation, both genetic and developmental; and the larger thorax of G. b. beringei to adaptation to reduced oxygen pressure at high altitudes, again as a product of both genetic differences and environmental influences during development.

Ecology, not host phylogeny, shapes the oral microbiome in closely related species of gorillas

“…Mountain gorillas live at elevation of up to 3,800 masl (Williamson et al, 2013) and hence are exposed to hypoxic stress (Ruff et al, 2022). They also show higher abundance of Neisseria and Veillonella compared to the other two gorilla subspecies, which live at considerably lower altitudes (Figures 5b and S8d).…”

Carpal allometry of African apes among mammals

“…Several studies have noted that gorillas have generally shorter and broader hands than chimpanzees (Inouye, 1992;Midlo, 1934;Schultz, 1927Schultz, , 1936Schultz, , 1956, which may help to preserve the integrity of the metacarpophalangeal joint during knuckle-walking (Susman, 1979). Within the genus Gorilla, Gorilla beringei, the more terrestrial and higher body mass species, (Doran, 1996(Doran, , 1997Doran & McNeilage, 1998;Doran-Sheehy et al, 2009;Remis, 1998;Schaller, 1963;Tuttle & Watts, 1985) has shorter third metacarpals and manual proximal phalanges than Gorilla gorilla (Ruff et al, 2022). Similar dimensional trends have been recorded in African ape carpals (Dainton & Macho, 1999).…”

Ecology, Not Host Phylogeny, Shapes the Oral Microbiome in Closely Related Species

“…For these reasons, regulation of NO metabolism is thought to be beneficial to high-altitude adaptation (Beall et al 2012). Mountain gorillas live at an elevation of up to 3,800 masl (Williamson et al 2013) and, hence, experience hypoxic stress (Ruff et al 2022). They also show a higher abundance of Neisseria and Veillonella compared with the other two gorilla subspecies (figs.…”