DOI: 10.5061/dryad.tqjq2bvzq
title: 3D skeletal pelvic landmarks from anthropoid primates

description: Objectives: The presence of sexual dimorphism in the birth canals of
 anthropoid primates is well-documented, and birth canal dimorphism tends
 to be especially robust among species that give birth to relatively large
 neonates. However, it is less clear whether birth canal dimorphism is
 accompanied by dimorphism in parts of the pelvis not directly under
 selection for birth, particularly including bi-iliac breadth,
 biactetabular breadth, lengths of the ischium and ilium, and 3D shape.
 This study investigates the patterns of dimorphism among anthropoid
 primates in those parts of the pelvis which do not directly contribute to
 the bony birth canal, here termed the non-obstetric pelvis. Methods: 3D
 landmark data were collected on the bony pelves of 899 anthropoid
 primates. Specifically, landmark data were collected on parts of the
 pelvis not thought to be directly involved in selection for parturition,
 including portions of the posterior and superior ilium, acetabulum, and
 lateral ischium. principal components analysis and Euclidean distance
 matrix analysis were used to ascertain sexual dimorphism in pelvic sizes
 and shapes within each species. Results: Results show that dimorphism in
 non-obstetric pelvic size and shape exists across anthropoids, just as is
 seen in the birth canal. However, the magnitude of dimorphism in
 non-obstetric pelvic shape tends to be greater among anthropoid species
 that give birth to relatively large neonates compared to those birthing
 smaller neonates relative to maternal pelvic size. Conclusions: Though all
 anthropoids included in the study show some degree of sexual dimorphism in
 non-obstetric pelvic size and/or shape, species which give birth to large
 neonates relative to maternal pelvic size have the highest levels of
 dimorphism in pelvic shape. Moreover, the magnitude of dimorphism in
 certain parts of the non-obstetric pelvis mirrors patterns seen in the
 birth canal. The results of this study are promising for ascertaining
 pelvic dimorphism and relative neonate size in fossil primates,
 particularly in fragmentary remains which do not preserve a complete bony
 birth canal.
description: The 3D coordinates in this dataset were collected using a
 Microscribe MX 3D Digitizer. The dataset included here are the raw
 landmark data for each specimen. Skeletal pelves were articulated using
 putty and rubber bands, and the following landmarks were
 collected:   
 Landmark #  Landmark Title Description 1 L PIIS Left Posterior Inferior Iliac Spine 2 L PSIS Left Posterior Superior Iliac Spine 3 L sup iliac crest Left superior-most point on iliac crest 4 L ASIS Left Anterior Superior Iliac Spine 5 L lat SI joint Left lateral-most point on SI joint 6 L arcuate SI ilium Left intersection of arcuate line & SI joint 7 L lateral arcuate line Left lateral-most point on arcuate line 8 L ant iliac neck Left narrowest point along the anterior iliac neck 9 L dors iliac neck Left narrowest point along the posterior iliac neck 10 L pubis arcuate line Left intersection of pubis & ilium on arcuate line 11 L pub acetabulum Left intersection of pubis & ilium on acetabular rim 12 L sup acetab Left superior-most point on acetabular rim 13 L dorsal acetab Left dorsal-most point on acetabular rim 14 L caudal acetab Left caudal-most point on acetabular rim 15 L acetab center Left center of acetabular fossa 16 L dorsal acetab isch Left intersection of ilium and ischium posterior to acetabulum 17 L ischial spine Left ischial spine along medial-most point 18 L post ishial ramus Left narrowest point along the posterior ischial ramus 19 L post tuberosity Left posterior-most point along ischial tuberosity 20 L ant tuberosity Left anterior-most point along ischial tuberosity 21 L lat ischial ramus Left lateral point along deepest curve of ischial ramus 22 L obt ischial ramus Left inferior-most point along ischiopubic ramus 23 inf pub symphysis Midline Inferior-most point on pubic symphysis 24 sup pub symphysis Midline superior-most point on pubic symphysis 25 dorsal S1 Midline dorsal point on S1 vertebral body 26 ventral S1 Midline ventral point on S1 vertebral body 27 left S1 Left lateral-most point on S1 vertebral body 28 left sup ala Left lateral-most point on superior sacral ala 29 inf S1 Midline junction of S1-S2 30 inf S2 Midline junction of S2-S3 31 inf Sacrum Midline inferior-most point on sacrum 32 right S1 Right lateral-most point on S1 vertebral body 33 right sup ala Right lateral-most point on superior sacral ala 34 R PIIS Right Posterior Inferior Iliac Spine 35 R PSIS Right Posterior Superior Iliac Spine 36 R sup iliac crest Right superior-most point on iliac crest 37 R ASIS Right Anterior Superior Iliac Spine 38 R lat SI joint Right lateral-most point on SI joint 39 R lateral arcuate line Right lateral-most point on arcuate line 40 R ant iliac neck Right narrowest point along the anterior iliac neck 41 R dorsal iliac neck Right narrowest point along the posterior iliac neck 42 R pubis arcuate line Right intersection of pubis & ilium on arcuate line 43 R pub acetab Right intersection of pubis & ilium on acetabular rim 44 R sup acetab Right superior-most point on acetabular rim 45 R dorsal acetab Right dorsal-most point on acetabular rim 46 R caudal acetab Right caudal-most point on acetabular rim 47 R acetab center Right center of acetabular fossa 48 R dorsal acetab isch Right intersection of ilium and ischium posterior to acetabulum 49 R ischial spine Right ischial spine along medial-most point 50 R post ishial ramus Right narrowest point along the posterior ischial ramus 51 R post tuberosity Right posterior-most point along ischial tuberosity 52 R ant tuberosity Right anterior-most point along ischial tuberosity 53 R lat ischial ramus Right lateral point along deepest curve of ischial ramus 54 R obt ischial ramus Right inferior-most point along ischiopubic ramus The following link is a figure depicting the location of each landmark collection location (only the left side is shown for bilaterally collected landmarks): https://docs.google.com/document/d/1CJvDDgeio2lVgV32lewatqEBzdR6SIrGD01tIdu1_-4/edit?usp=sharing  
description: The dataset included here has 921 specimens, as some sample sizes
 collected were too small for sufficient power to include in the published
 AJPA article. However, these extra specimens are included in the dataset
 for completeness.