Differences in the Skull Morphology between Juvenile and Adult Green Turtles: Implications for the Ontogenetic Diet Shift

  title={Differences in the Skull Morphology between Juvenile and Adult Green Turtles: Implications for the Ontogenetic Diet Shift},
  author={Hideaki Nishizawa and M. Asahara and Naoki Kamezaki and Nobuaki Arai},
Abstract: Skull morphology was compared between juvenile and adult green turtles by geometric morphometrics. The size of the orbit and length of the supraoccipital in relation to the centroid size were larger in juveniles than in adults, while the relative sizes of the infratemporal fossae and parietal were larger in the latter than in the former. The difference in the relative length of the supraoccipital did not predict the maintenance of functional equivalence of trophic structures, probably… 

Skull ontogenetic variation of the coastal developmental stage of the loggerhead turtle (Caretta caretta) in the western South Atlantic Ocean

It is suggested that these skull changes are associated with the diet shift of the loggerhead turtle specimens, providing the skull with greater mechanical resistance and enabling a change in feeding strategy from soft organisms to hard-shelled preys.

The Head and Neck Anatomy of Sea Turtles (Cryptodira: Chelonioidea) and Skull Shape in Testudines

The cranial anatomy in two sea turtles, the loggerhead (Caretta caretta) and Kemp’s ridley, is described for a better understanding of sea turtle functional anatomy and morphological variation.

Intra-specific variation in skull morphology of juvenile Chelonia mydas in the southwestern Atlantic Ocean

Con Conserving priority Caribbean nesting grounds during regional management initiatives might protect phenotypic variability and ultimately population diversity and resilience and imply evolutionary consequences for genetic diversity and trophic polymorphism if there is increased future bias towards CM-A8.

Redescription of the skull of the Australian flatback sea turtle, Natator depressus, provides new morphological evidence for phylogenetic relationships among sea turtles (Chelonioidea)

The Australian flatback sea turtle, Natator depressus, is often excluded from comparisons and it is the most poorly known of the seven extant species of Chelonioidea, so descriptions of its skull morphology are limited and conflict.

Ontogenetic allometry underlies trophic diversity in sea turtles (Chelonioidea)

Despite only comprising seven species, extant sea turtles (Cheloniidae and Dermochelyidae) display great ecological diversity, with most species inhabiting a unique dietary niche as adults. This

Temporal bone arrangements in turtles: an overview.

  • I. Werneburg
  • Environmental Science
    Journal of experimental zoology. Part B, Molecular and developmental evolution
  • 2012
In this review on almost forgotten literature, a summary of ten potential factors that may act on the skull to shape the temporal region of turtles are summarized.

A juvenile specimen of Neusticemys neuquina (Testudinata: Thalassochelydia) from the Upper Jurassic of Neuquén Basin (Neuquén Province, Argentina)

ABSTRACT Cranial and postcranial remains of a juvenile specimen from the lower section of the Vaca Muerta Formation (Lower Tithonian) recovered at Cerro Lotena (Neuquén Province, Argentina) are

Integrating morphological and genetic data at different spatial scales in a cosmopolitan marine turtle species: challenges for management and conservation


The efficacy of computed tomography scanning versus surface scanning in 3D finite element analysis

Finite element analysis (FEA) is a commonly used application in biomechanical studies of both extant and fossil taxa to assess stress and strain in solid structures such as bone. FEA can be performed



Ecological correlates and evolutionary divergence in the skull of turtles: a geometric morphometric assessment.

The adaptive radiation of the Testudinoidea is revealed to demonstrate a clear relationship between the skull shape and life style, and it is revealed that morphological specialization was related to both diet and habitat.

Chondrocranial development in larval Rana sylvatica (Anura: Ranidae): Morphometric analysis of cranial allometry and ontogenetic shape change

The anuran chondrocranium is not a static structure during premetamorphic stages and allometric patterns generally follow scaling predictions for tetrapod cranial development.

Skull allometry in the marine toad, Bufo marinus

  • J. Birch
  • Environmental Science
    Journal of morphology
  • 1999
To determine whether skull shape increases isometrically, linear measurements and geometric morphometrics were used to quantify shape variation in a size series of 69 skulls from the marine toad, B. marinus, and results imply that morphological allometry may still result in kinematic isometry.

Ontogenetic changes in diet and habitat use in green sea turtle (Chelonia mydas) life history

This is the first study to capture the entire life history of green turtles in terms of foraging ecology and supports the ontogenetic shift previously observed in traditional diet and behavioral studies of green Turtles.

Individual variation in feeding habitat use by adult female green sea turtles (Chelonia mydas): are they obligately neritic herbivores?

The results and previous findings suggest that ontogenetic habitat shifts by sea turtles are facultative, and consequently, their life histories are polymorphic.

Comparative Phylogeny and Historical Perspectives on Population Genetics of the Pacific Hawksbill (Eretmochelys imbricata) and Green Turtles (Chelonia mydas), Inferred from Feeding Populations in the Yaeyama Islands, Japan

Historical patterns of population dynamics and differentiation in hawksbill and green turtles in the Pacific were estimated from feeding populations in the Yaeyama Islands, Japan to indicate that hawks bill and green turtle probably underwent very similar patterns and processes ofpopulation dynamics over the last million years.

A Review of Biological Studies on Sea Turtles in Japan

To clarify the research history of sea turtle biology in Japan, a total of 256 scientific publications are reviewed in relation to the following six categories: taxonomy, distribution, development,

Intrinsic Mechanics and Control of Fast Cranio-Cervical Movements in Aquatic Feeding Turtles1

It is proposed that erroneous folding of the neck (i.e., diverging from the highly persistent retracted configuration) might be avoided through the presence of a subtle click system at the level of the joint between cervical vertebrae 5 and 6.

Geometric morphometrics for biologists : a primer

The second edition of "Geometric Morphometrics for Biologists" represents the current state of the art and adds new examples and summarizes recent literature, as well as provides an overview of new software and step-by-step guidance through details of carrying out the analyses.