DOI: 10.5061/dryad.hmgqnk9dc
title: Data from: More than one way to be a giant: convergence and disparity in the hip joints of saurischian dinosaurs

description: Saurischian dinosaurs evolved seven orders of magnitude in body mass, as
 well as a wide diversity of hip joint morphology and locomotor postures.
 The very largest saurischians possess incongruent bony hip joints,
 suggesting that large volumes of soft tissues mediated hip articulation.
 To understand the evolutionary trends and functional relationships between
 body size and hip anatomy of saurischians, we tested the relationships
 among discrete and continuous morphological characters using
 phylogenetically corrected regression. Giant theropods and sauropods
 convergently evolved highly cartilaginous hip joints by reducing
 supraacetabular ossifications, a condition unlike that in early
 dinosauromorphs. However, transitions in femoral and acetabular soft
 tissues indicate that large sauropods and theropods built their hip joints
 in fundamentally different ways. In sauropods, the femoral head possesses
 irregularly rugose subchondral surfaces for thick hyaline cartilage. Hip
 articulation was achieved primarily using the highly cartilaginous femoral
 head and the supraacetabular labrum on the acetabular ceiling. In
 contrast, theropods covered their femoral head and neck with thinner
 hyaline cartilage and maintained extensive articulation between the
 fibrocartilaginous femoral neck and the antitrochanter. These findings
 suggest that the hip joints of giant sauropods were built to sustain large
 compressive loads whereas those of giant theropods experienced compression
 and shear forces.
description: Discrete characters: The bony hip joints of saurischian-line
 archosaurs were examined for discrete characters, including osteological
 correlates of hip joint articular soft tissues. We identified 14
 osteological characters based on osteological correlates of homologous
 articular soft tissues among extant diapsids (Tsai and Holliday,
 2015) Continuous characters: Linear dimensions of
 fossils were measured using a SPI 31-518-4 dial caliper and a tape measure
 on physical specimens, as well as from reconstructed 3D surface models of
 hip joints using the <i>measure distance </i>function of
 Geomagic (V11 see Appendix S1 of manuscript). Surface area dimensions were
 measured from reconstructed 3D surface models of hip joints by
 highlighting relevant osteological correlates and using the
 <i>select area</i> function of Geomagic (V11 see Appendix S1
 of manuscript). Phylogenetic trees: Composite
 phylogenetic trees (Fig. 4) were constructed using Mesquite (V2.73) based
 on published studies (See citations in manuscript), with branch lengths
 based on hypothesized divergence date between sister clades and sister
 taxa.
description: The dataset includes five tree files (.phy) and two text
 documents for <strong>continuous characters</strong> and
 <strong>discrete characters </strong>respectively.
 Among the tree files, ArchoMS.phy contains the
 "consensus" tree used in this study. The other trees are of
 alternative topologies in light of contentiously placed taxa, as explained
 in Figure 4.  The contents of the text documents is
 best viewed when opened using Excel, as their columns correspond to the
 continuous and discrete characters. Continuous characters are presented as
 logged values. In <b>continous
 characters</b>, the column's correspondence to characters used
 in this study are as follows 
 Column 1: Femur length   Column 6: Femoral head circumference   Column 7: Femoral head height   Column 8: FAA length   Column 9: Femoral head width   Column 10: Acetabular length   Column 13: Acetabular depth   Column 14: Acetabular height   Column 15: Acetabular circumference   Column 16: Femoral subchondral surface area   Column 17: Femoral growth plate surface area   Column 18: Femoral metaphyseal collar surface area   Column 19: Acetabular labrum attachment surface area   Column 20: Ilial bony antitrochanter area   Column 21: Bony antitrochanter surface area   Column 22: Bony acetabulum   Column 23: Acetabular fossa For <strong>discrete</strong> <strong>characters</strong>, the columns' correspondence to characters used in this study are as follows:   Column 21:  Perforated acetabulum Column 30 Lateral expansion of the supraacetabular rim Column 31 Orientation of the supraacetabular rim Column 26 Expansion of the bony antitrochanter Column 34 Shape of the ischial peduncle of the ilium Column 23 Co-ossification of the bony antitrochanter Column 5 Femoral head deflection Column 9 Surface texture of the proximal femoral growth plate Column 10 Concentration of irregular rugosities on the femoral head Column 18 Transphyseal striations Column 19 Fovea capitis Column 20 Ischiofemoral ligament sulcus Column 11 Cartilage cone trough Column 14 Expanded metaphyseal Collar