Growth and Development at the Sphenoethmoidal Junction in Perinatal Primates

Abstract

Integration of the sphenoid and ethmoid bones during early postnatal development is poorly described in the literature. A uniquely prolonged patency of sphenoethmoidal synchondrosis or prespheno-septal synchondrosis (PSept) has been attributed to humans. However, the sphenoethmoidal junction has not been studied using a comparative primate sample. Here, we examined development of the sphenoethmoidal interface using ontogenetic samples of Old and New World monkeys, strepsirrhine primates (lemurs and lorises), and a comparative sample of other mammals. Specimens ranging from late fetal to 1 month postnatal age were studied using histology, immunohistochemistry, and micro-computed tomography methods. Our results demonstrate that humans are not unique in anterior cranial base growth at PSept, as it is patent in all newborn primates. We found two distinctions within our sample. First, nearly all primates exhibit an earlier breakdown of the nasal capsule cartilage that abuts the orbitosphenoid when compared to nonprimates. This may facilitate earlier postnatal integration of the basicranium and midface and may enhance morphological plasticity in the region. Second, the PSept exhibits a basic dichotomy between strepsirrhines and monkeys. In strepsirrhines, the PSept has proliferating chondrocytes that are primarily oriented in a longitudinal plane, as in other mammals. In contrast, monkeys have a convex anterior end of the presphenoid with a radial boundary of cartilaginous growth at PSept. Our findings suggest that the PSept acts as a "pacemaker" of longitudinal facial growth in mammals with relatively long snouts, but may also contribute to facial height and produce a relatively taller midface in anthropoid primates. Anat Rec, 300:2115-2137, 2017. © 2017 Wiley Periodicals, Inc.

Inward collapse of the nasal cavity: Perinatal consolidation of the midface and cranial base in primates

“…As in previous samples, these tissues were serially sectioned at 10 μm, and every 5th to 10th section was alternately stained using Gomori trichrome and hematoxylin and eosin. The descriptive findings on Lemur catta were previously reported (Smith et al, 2017) and are updated here with findings based on new procedures.…”

“…(b) A nearby section (0.2 mm medial to the section in 6a) shows reactivity to Collagen II antibodies. Note an irregular margin on the mucosal side, in which a thin margin of collagen II (−) matrix has a "scalloped" Gilse, 1927) and many other mammals (Smith et al, 2017) it remains in its cartilaginous state throughout fetal development, and absorption or ossification is delayed until postnatal stages. Prenatal stages are inherently easier to study than postnatal stage, based on more manageable size for histological sectioning.…”

“…At birth, portions of the capsule remain cartilaginous in many mammals that have been This article include AR WOW Video. Video can be viewed at https:// studio.brightcove.com/products/videocloud/media/videos/6200578659001 described at that age (Maier, 2000;Smith et al, 2017;Zeller, 1987). While some other regions of the chondrocranium are also observed to have delayed ossification (e.g., parts of the temporal bone), all midline elements posterior to the nasal capsule begin ossification prior to birth, while leaving synchondroses for continued interstitial expansion (Smith, Curtis, Bhatnagar, & Santana, 2020;Starck, 1967).…”

The Anatomical Record Uncovers Nature's Extreme Species and How They Have Survived in a Novel Two‐Volume Special Issue

“…Just ask anyone in the field (except Tim, who is as modest as they come and will squint, blush, and squirm in his chair when he reads this essay.) Indeed, our journal has reaped the bounty of his science, publishing work by Tim and his many colleagues stemming back over 20 years (e.g., Smith et al, , , , , , , , , Smith and Bhatnager, ; Smith and Rossie, ; Bhatnagar and Smith, ; Burrows and Smith, ; DeLeon and Smith, ; Roslinski et al, ; Eiting et al, ; Dennis et al, , .) Indeed, Tim has also co‐Guest Edited three of our most successful Special Issues on: special senses of primates (Dominy et al, ; Laitman, ); primate functional morphology and biomechanics (Laitman, ; Laitman and Albertine, ; Organ et al, ); and on the vertebrate nose (Van Valkenburgh et al, ; Laitman, ; Laitman and Albertine, .)…”

AR Presents Celebration of the 40th Anniversary of the Congenital Anomaly Research Center at Kyoto University Graduate School of Medicine, Kyoto, Japan

“…Other top human embryologists of the early 1900s—CR Bardeen, RR Bensley, EA Read, SH Gage, RE Sheldon, HH Donaldson, EH Dunn, and GL Streeter—collaborated on a joint paper in the Journal (Bardeen et al, ). Subsequent notable papers are authored by Frederic T. Lewis (Lewis, , 1912), Clarence L. Turner in 1920 (Turner, ), HE Jordan (Jordan, ), Leslie B. Arey (Arey, ), Ernst De Vries (De Vries, ), Edward A. Boyden (Boyden, ; Boyden, ; Boyden and Rigler, ), Peter Gruenwald (Gruenwald, ), G. Gordon Robinson and S. Lea O'Neill (Gordon Robinson, 1948), Ian M. Monie (Monie, ), Eileen M. Otis and Robert Brent (Otis, 1954), Donald G. McKay et al (McKay et al, ), Ronan O'Rahilly and Fabiola Müller (O'Rahilly, 1984), Richard P. Dickey and Raymond F. Gasser (Dickey and Gasser, 1993) Robert J. Tomanek (Tomanek, ), and Timothy D. Smith et al (Smith et al, ). As a side bar, Ian Monie taught me embryology while I was a postdoctoral fellow at the University of California, San Francisco in the early 1980s.…”