CONVERGENCE AND REMARKABLY CONSISTENT CONSTRAINT IN THE EVOLUTION OF CARNIVORE SKULL SHAPE

AbstractRunt-related transcription factor 2 (RUNX2) is critical for the development of the vertebrate bony skeleton. Unlike other RUNX family members, RUNX2 possesses a variable poly-glutamine, poly-alanine (QA) repeat domain. Natural variation within this repeat is able to alter the transactivation potential of RUNX2, acting as an evolutionary ‘tuning knob’ suggested to influence mammalian skull shape. However, the broader role of the RUNX2 QA repeat throughout vertebrate evolution is unknown. In this perspective, we examine the role of the RUNX2 QA repeat during skeletal development and discuss how its emergence and expansion may have facilitated the evolution of morphological novelty in vertebrates.

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Pattern and pace of morphological change due to variable human impact: the case of Japanese macaques

Primates ◽

10.1007/s10329-021-00933-7 ◽

2021 ◽

Author(s):

Madeleine Geiger

Keyword(s):

Body Size ◽

Human Impact ◽

Morphological Variation ◽

Japanese Macaques ◽

Linear Measurements ◽

Skull Shape ◽

Rates Of Change ◽

Animal Populations ◽

Captive Populations ◽

In Captivity

AbstractHuman impact influences morphological variation in animals, as documented in many captive and domestic animal populations. However, there are different levels of human impact, and their influence on the pattern and rate of morphological variation remains unclear. This study contributes to the ongoing debate via the examination of cranial and mandibular shape and size variation and pace of change in Japanese macaques (Macaca fuscata). This species is ideal for tackling such questions because different wild, wild-provisioned, and captive populations have been monitored and collected over seven decades. Linear measurements were taken on 70 skulls from five populations, grouped into three ‘human impact groups’ (wild, wild-provisioned, and captive). This made it possible to investigate the pattern and pace of skull form changes among the human impact groups as well as over time within the populations. It was found that the overall skull shape tends to differ among the human impact groups, with captive macaques having relatively longer rostra than wild ones. Whether these differences are a result of geographic variation or variable human impact, related to nutritional supply and mechanical properties of the diet, is unclear. However, this pattern of directed changes did not seem to hold when the single captive populations were examined in detail. Although environmental conditions have probably been similar for the two examined captive populations (same captive locality), skull shape changes over the first generations in captivity were mostly different. This varying pattern, together with a consistent decrease in body size in the captive populations over generations, points to genetic drift playing a role in shaping skull shape and body size in captivity. In the captive groups investigated here, the rates of change were found to be high compared to literature records from settings featuring different degrees of human impact in different species, although they still lie in the range of field studies in a natural context. This adds to the view that human impact might not necessarily lead to particularly fast rates of change.

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Quantitative Assessment of Shape Deformation of Regional Cranial Bone for Evaluation of Surgical Effect in Patients with Craniosynostosis

Applied Sciences ◽

10.3390/app11030990 ◽

2021 ◽

Vol 11 (3) ◽

pp. 990

Author(s):

Min Jin Lee ◽

Helen Hong ◽

Kyu Won Shim

Keyword(s):

Quantitative Assessment ◽

Deformable Registration ◽

Occipital Bone ◽

Cranial Bone ◽

Shape Deformation ◽

Surface Model ◽

Cephalic Index ◽

Skull Shape ◽

Quantification Method ◽

Parietal Bones

Surgery in patients with craniosynostosis is a common treatment to correct the deformed skull shape, and it is necessary to verify the surgical effect of correction on the regional cranial bone. We propose a quantification method for evaluating surgical effects on regional cranial bones by comparing preoperative and postoperative skull shapes. To divide preoperative and postoperative skulls into two frontal bones, two parietal bones, and the occipital bone, and to estimate the shape deformation of regional cranial bones between the preoperative and postoperative skulls, an age-matched mean-normal skull surface model already divided into five bones is deformed into a preoperative skull, and a deformed mean-normal skull surface model is redeformed into a postoperative skull. To quantify the degree of the expansion and reduction of regional cranial bones after surgery, expansion and reduction indices of the five cranial bones are calculated using the deformable registration as deformation information. The proposed quantification method overcomes the quantification difficulty when using the traditional cephalic index(CI) by analyzing regional cranial bones and provides useful information for quantifying the surgical effects of craniosynostosis patients with symmetric and asymmetric deformities.

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A prepotent factor in the determination of skull shape

American Journal of Anatomy ◽

10.1002/aja.1000540207 ◽

1934 ◽

Vol 54 (2) ◽

pp. 333-346 ◽

Cited By ~ 6

Author(s):

J. A. Dye ◽

F. S. Kinder

Keyword(s):

Skull Shape

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SKULL SHAPE EVOLUTION IN DUROPHAGOUS CARNIVORANS

Evolution ◽

10.1111/evo.12059 ◽

2013 ◽

Vol 67 (7) ◽

pp. 1975-1993 ◽

Cited By ~ 57

Author(s):

Borja Figueirido ◽

Zhijie Jack Tseng ◽

Alberto Martín-Serra

Keyword(s):

Shape Evolution ◽

Skull Shape

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Enhanced head-skull shape learning using statistical modeling and topological features

Medical & Biological Engineering & Computing ◽

10.1007/s11517-021-02483-y ◽

2022 ◽

Author(s):

Tan-Nhu Nguyen ◽

Vi-Do Tran ◽

Ho-Quang Nguyen ◽

Duc-Phong Nguyen ◽

Tien-Tuan Dao

Keyword(s):

Statistical Modeling ◽

Skull Shape ◽

Topological Features ◽

Shape Learning

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Dynamic cranioplasty for brachycephaly in Apert syndrome: long-term follow-up study

Journal of Neurosurgery ◽

10.3171/jns.2001.94.5.0757 ◽

2001 ◽

Vol 94 (5) ◽

pp. 757-764 ◽

Cited By ~ 10

Author(s):

José Guimarães-Ferreira ◽

Fredrik Gewalli ◽

Pelle Sahlin ◽

Hans Friede ◽

Py Owman-Moll ◽

...

Keyword(s):

Cell Mass ◽

Apert Syndrome ◽

Long Term Results ◽

Safe Procedure ◽

Content Type ◽

Skull Shape ◽

The Mean ◽

Fine Print

Object. Brachycephaly is a characteristic feature of Apert syndrome. Traditional techniques of cranioplasty often fail to produce an acceptable morphological outcome in patients with this condition. In 1996 a new surgical procedure called “dynamic cranioplasty for brachycephaly” (DCB) was reported. The purpose of the present study was to analyze perioperative data and morphological long-term results in patients with the cranial vault deformity of Apert syndrome who were treated with DCB. Methods. Twelve patients have undergone surgery performed using this technique since its introduction in 1991 (mean duration of follow-up review 60.2 months). Eleven patients had bicoronal synostosis and one had a combined bicoronal—bilambdoid synostosis. Perioperative data and long-term evolution of skull shape visualized on serial cephalometric radiographs were analyzed and compared with normative data. Changes in mean skull proportions were evaluated using a two-tailed paired-samples t-test, with differences being considered significant for probability values less than 0.01. The mean operative blood transfusion was 136% of estimated red cell mass (ERCM) and the mean postoperative transfusion was 48% of ERCM. The mean operative time was 218 minutes. The duration of stay in the intensive care unit averaged 1.7 days and the mean hospital stay was 11.8 days. There were no incidences of mortality and few complications. An improvement in skull shape was achieved in all cases, with a change in the mean cephalic index from a preoperative value of 90 to a postoperative value of 78 (p = 0.000254). Conclusions. Dynamic cranioplasty for brachycephaly is a safe procedure, yielding high-quality morphological results in the treatment of brachycephaly in patients with Apert syndrome.

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New specimen of <i>Cacops woehri</i> indicates differences in the ontogenetic trajectories among cacopine dissorophids

Fossil Record ◽

10.5194/fr-18-73-2015 ◽

2015 ◽

Vol 18 (1) ◽

pp. 73-80 ◽

Cited By ~ 6

Author(s):

N. B. Fröbisch ◽

A. Brar ◽

R. R. Reisz

Keyword(s):

Morphological Changes ◽

Lower Permian ◽

Ecological Diversity ◽

Large Specimen ◽

Skull Morphology ◽

Skull Shape ◽

Ontogenetic Trajectories ◽

Ontogenetic Trajectory ◽

Taxic Diversity

Abstract. The Lower Permian Dolese locality has produced numerous exquisitely preserved tetrapod fossils representing members of a lower Permian upland fauna. Therein, at least nine taxa of the clade Dissorophoidea, ranging in size from the large predaceous trematopid Acheloma to the miniaturized amphibamid Doleserpeton, highlight the great taxic and ecological diversity of this anamniote clade. Here we describe a large specimen of the dissorophid Cacops woehri, which was previously only known from the juvenile or subadult holotype skull. Another member of the genus Cacops present at the Dolese locality, Cacops morrisi, is also represented by specimens spanning juvenile, subadult, and adult stages, allowing for a comparison of morphological changes taking place in the late phases of the ontogenetic trajectory of cacopine dissorophids. The new find shows that, in contrast to C. morrisi and C. aspidephorus, C. woehri only undergoes relatively subtle changes in skull morphology in late ontogeny and retains the overall more gracile morphology into adult stages. This includes retention of the rather shallow skull shape as well as a pattern of sculpturing consisting of elongate ridges and grooves and a large occipital flange. This suggests somewhat different functional demands in C. woehri than in other known species of Cacops, possibly associated with a different ecology paralleling the great taxic diversity of dissorophoids at the Dolese locality.

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Endoscopic assisted suturectomy for primary craniosynostosis in infancy

Journal of Clinical Review & Case Reports ◽

10.33140/jcrc/03/02/00007 ◽

2018 ◽

Vol 3 (2) ◽

Keyword(s):

Intracranial Pressure ◽

Minimally Invasive ◽

Hospital Stay ◽

Teaching Hospital ◽

Head Circumference ◽

Analytical Study ◽

Intracranial Volume ◽

Minimally Invasive Approach ◽

Invasive Approach ◽

Skull Shape

Background: Multiple procedures have been used for the treatment of craniosynostosis, ranging from simple suturectomy to extensive calvarial vault remodeling. The optimal timing for surgery is still controversial. The goal of therapy is to provide adequate intracranial volume, in addition to an aesthetically almost normal skull shape. Endoscopic synostosis repair described in 1998 by Jimenez and Baron [1]. This technique allows for a less invasive method that can result in excellent longstanding reconstruction of the cranial skeleton. This method is a minimally invasive approach that has less morbidity involved with traditional reconstruction techniques. Aim: Evaluation of early endoscopic suturectomy and its impact on both neurological functions and cosmetic appearance of infants up to 6 months of age suffering primary craniosynostosis. Methodology: This is a prospective analytical study of 50 patients with primary non syndromic craniosynostosis either single suture or multiple sutures, up to sixth months of age; with evident of skull shape deformity and or manifestations of increase intracranial pressure. from; October 2009 to October 2016 were managed byendoscopic assisted suturectomy the approach of Jimenez and Baron, in both Neurosurgery Department Shebin Elkom teaching hospital and Neurosurgery Department in Elsahel teaching hospital. Clinical and radiological follow up for six months postoperative. Results: This is a prospective analytical study of 50 patients with primary craniosynostosis, 28 patients are male and 22 patients are female. The age of patients range from one and half months to sixth months. The majority of cases presented with deformity alone 68%. Other clinical presentations as manifestations of increased intracranial pressure, fits, and delayed milestones plus deformity was 20%, 8%, and 4% respectively. Estimated blood loss, the mean loss was 56cc, minimum 30cc, and maximum was 100cc, with stander deviation ±18cc.The minimum hospital stay was one day and maximum was three days.There is significant change of head shape and head circumference postoperatively this observed by highly significant P value in head circumference (< 0.001). Conclusion: Endoscopic assisted suturectomy is minimally invasive approach with a very narrow range of complications, very limited need to blood transfusion and if it occurs, it is small volume in relation to total volume. Very short ICU and hospital stay also decrease the economic load.

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