title: Body composition in Pan paniscus compared with Homo sapiens has implications for changes during human evolution.
abstract: The human body has been shaped by natural selection during the past 4-5 million years. Fossils preserve bones and teeth but lack muscle, skin, fat, and organs. To understand the evolution of the human form, information about both soft and hard tissues of our ancestors is needed. Our closest living relatives of the genus Pan provide the best comparative model to those ancestors. Here, we present data on the body composition of 13 bonobos (Pan paniscus) measured during anatomical dissections and compare the data with Homo sapiens. These comparative data suggest that both females and males (i) increased body fat, (ii) decreased relative muscle mass, (iii) redistributed muscle mass to lower limbs, and (iv) decreased relative mass of skin during human evolution. Comparison of soft tissues between Pan and Homo provides new insights into the function and evolution of body composition.
authors.affiliation: Department of Anthropology, University of California, Santa Cruz, CA 95064; azihlman@ucsc.edu bolterd@yosemite.edu.
authors.forename: Adrienne L
authors.initials: AL
authors.lastname: Zihlman
authors.affiliation: Department of Anthropology, Modesto College, Modesto, CA 95350; Evolutionary Studies Institute, University of the Witwatersrand, Johannesburg 2050, South Africa azihlman@ucsc.edu bolterd@yosemite.edu.
authors.forename: Debra R
authors.initials: DR
authors.lastname: Bolter
mesh_terms: D000273:Adipose Tissue / Q000033:anatomy & histology; D000328:Adult; D000818:Animals; D005075:Biological Evolution; D001823:Body Composition; D001835:Body Weight; D001842:Bone and Bones / Q000033:anatomy & histology; D001921:Brain / Q000033:anatomy & histology; D005260:Female; D006801:Humans; D008297:Male; D009132:Muscles / Q000033:anatomy & histology; D009929:Organ Size; D019974:Pan paniscus / Q000033:anatomy & histology*; D012641:Selection, Genetic; D012867:Skin / Q000033:anatomy & histology; D013045:Species Specificity
keywords: Homo sapiens; Pan paniscus; body composition; bonobo; human evolution