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Body size is often hypothesized to facilitate or constrain morphological diversity in the cranial, appendicular, and axial skeletons. However, how overall body shape scales with body size ( i.e. , body shape allometry) and whether these scaling patterns differ between ecological groups remains poorly investigated. Here, we test whether and how the relationships between body shape, body size, and limb lengths differ among species with different locomotor specializations, and describe the underlying morphological components that contribute to body shape evolution among squirrel (Sciuridae) ecotypes. We quantified the body size and shape of 87 squirrel species from osteological specimens held at museum collections. Using phylogenetic comparative methods, we first found that body shape and its underlying morphological components scale allometrically with body size, but these allometric patterns differ among squirrel ecotypes: chipmunks and gliding squirrels exhibited more elongate bodies with increasing body sizes whereas ground squirrels exhibited more robust bodies with increasing body size. Second, we found that only ground squirrels exhibit a relationship between forelimb length and body shape, where more elongate species exhibit relatively shorter forelimbs. Third, we found that the relative length of the ribs and elongation or shortening of the thoracic region contributes the most to body shape evolution across squirrels. Overall, our work contributes to the growing understanding of mammalian body shape evolution and how it is influenced by body size and locomotor ecology, in this case from robust subterranean to gracile gliding squirrels.
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The Charles Fox Guitar-Building Method, Part Three
In this episode of the landmark series, the back and top plates are braced and glued to the rim to form the body of the guitar. The body is then bound and purfled using Fox’ distinctive method of fitting everything dry, taping it in place, and running superglue into the seams.
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- Award ID(s):
- 1700531
- PAR ID:
- 10252110
- Date Published:
- Journal Name:
- American lutherie
- ISSN:
- 1041-7176
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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