Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Changes in the Appendicular Skeleton with Age01:09

Changes in the Appendicular Skeleton with Age

3.3K
The upper and lower limb initially develops as a small bulge called a limb bud, which appears on the lateral side of the early embryo. The upper limb bud appears near the end of the fourth week of development, with the lower limb bud appearing shortly after.
Initially, the limb buds consist of a core of mesenchyme covered by a layer of ectoderm. The ectoderm at the end of the limb bud thickens to form a narrow crest called the apical ectodermal ridge. This ridge stimulates the underlying...
3.3K
Bone Formation by Endochondral Ossification01:24

Bone Formation by Endochondral Ossification

7.8K
Bone formation, or ossification, begins around the sixth to seventh week of embryonic development. Most bones develop from a cartilaginous template through the process of endochondral ossification. Cartilage formation begins when clusters of mesenchymal cells differentiate into chondrocytes. These chondrocytes proliferate rapidly and secrete an extracellular matrix that becomes encased in a membrane called the perichondrium. The resulting cartilage model provides a template that resembles the...
7.8K
Convergent Evolution01:54

Convergent Evolution

31.2K
Evolution shapes the features of organisms over time, ensuring that they are suited for the environments in which they live. Sometimes, selection pressure leads to the rise of similar but unrelated adaptations in organisms with no recent common ancestors, a process known as convergent evolution.
31.2K
The Fossil Record02:56

The Fossil Record

26.9K
The fossil record documents only a small fraction of all organisms that have ever inhabited Earth. Fossilization is a rare process, and most organisms never become fossils. Moreover, the fossil record only exhibits fossils that have been discovered. Nevertheless, sedimentary rock fossils of long-lived, abundant, hard-bodied organisms dominate the fossil record. These fossils offer valuable information, such as an organism's physical form, behavior, and age. Studying the fossil record helps...
26.9K
Bone Formation by Intramembranous Ossification01:29

Bone Formation by Intramembranous Ossification

9.7K
Intramembranous ossification is one of the two processes involved in the development of bones within an embryo. The flat bones of the face, most of the cranial bones, and the clavicles are formed via this process. During intramembranous ossification, the bones develop directly from sheets of undifferentiated mesenchymal connective tissue.
The process begins when mesenchymal cells in the embryonic skeleton gather together and differentiate into osteogenic cells, which then develop into ...
9.7K
Development of the Limb Synovial Joints01:07

Development of the Limb Synovial Joints

2.1K
Joints form during embryonic development in conjunction with the formation and growth of the associated bones. The embryonic tissue that gives rise to all bones, cartilage, and connective tissues of the body is called mesenchyme.
The mesenchymal stem cells differentiate into chondrocytes that form the hyaline cartilage, and later the cartilaginous model of the bone. This model further transforms into a bone. This process is known as endochondral ossification.
During development, the limbs...
2.1K

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Earliest oceanic tetrapod ecosystem reveals rapid complexification of Triassic marine communities.

Science (New York, N.Y.)·2025
Same author

Articulated specimens provide new insights into the iconic Mesozoic shark genus <i>Sphenodus</i>.

Journal of systematic palaeontology·2025
Same author

The osteology, taxonomy, and phylogenetic placement of Seeleyosaurus guilelmiimperatoris (Plesiosauroidea, Microcleididae) from the Lower Jurassic Posidonia Shale of Germany.

Anatomical record (Hoboken, N.J. : 2007)·2025
Same author

Palaeohistology of Macrospondylus bollensis (Crocodylomorpha: Thalattosuchia: Teleosauroidea) from the Posidonienschiefer Formation (Toarcian) of Germany, with insights into life history and ecology.

Anatomical record (Hoboken, N.J. : 2007)·2024
Same author

Oldest record of Machimosaurini (Thalattosuchia, Teleosauroidea): teeth and scavenging traces from the Middle Jurassic (Bajocian) of Switzerland.

Royal Society open science·2024
Same author

The rise of macropredatory pliosaurids near the Early-Middle Jurassic transition.

Scientific reports·2023
Same journal

Therapeutic potential of crude protein extracts from two Egyptian freshwater snails Lanistes carinatus and Bellamya unicolor.

Scientific reports·2026
Same journal

Microbial contamination of donor corneas and post-keratoplasty endophthalmitis: a comparison between Japanese and U.S. eye banks using cold storage.

Scientific reports·2026
Same journal

Prevalence and contributing factors of virological non-suppression among adult patients on first-line antiretroviral therapy in tertiary hospitals in Ethiopia.

Scientific reports·2026
Same journal

An in vitro comparison of color stability between alkasite and different restorative materials in various staining solutions.

Scientific reports·2026
Same journal

Toward accessible mRNA LNP formulation: systematic evaluation of mixing strategies and key parameters.

Scientific reports·2026
Same journal

A network analysis of personality traits, mentalizing, and psychological health in Chinese college students.

Scientific reports·2026
See all related articles

Related Experiment Video

Updated: Dec 26, 2025

Dissection and Flat-mounting of the Threespine Stickleback Branchial Skeleton
08:02

Dissection and Flat-mounting of the Threespine Stickleback Branchial Skeleton

Published on: May 7, 2016

10.2K

Skeletal pathologies track body plan evolution in ichthyosaurs.

Judith M Pardo-Pérez1,2,3, Benjamin P Kear4, Erin E Maxwell5

  • 1Staatliches Museum für Naturkunde Stuttgart, Rosenstein 1, 70191, Stuttgart, Germany. judith.pardo-perez@smns-bw.de.

Scientific Reports
|March 8, 2020
PubMed
Summary
This summary is machine-generated.

Skeletal pathologies in Middle Triassic and Early Jurassic ichthyosaurs reveal significant shifts in body structure and behavior. These changes in marine reptiles reflect ecological transformations during the Mesozoic Marine Revolution.

More Related Videos

Three and Four-Dimensional Visualization and Analysis Approaches to Study Vertebrate Axial Elongation and Segmentation
12:59

Three and Four-Dimensional Visualization and Analysis Approaches to Study Vertebrate Axial Elongation and Segmentation

Published on: February 28, 2021

4.0K
Systematic Assessment of Mammalian Skull Specimens for Dental and Temporomandibular Joint Pathology
07:26

Systematic Assessment of Mammalian Skull Specimens for Dental and Temporomandibular Joint Pathology

Published on: August 22, 2022

1.7K

Related Experiment Videos

Last Updated: Dec 26, 2025

Dissection and Flat-mounting of the Threespine Stickleback Branchial Skeleton
08:02

Dissection and Flat-mounting of the Threespine Stickleback Branchial Skeleton

Published on: May 7, 2016

10.2K
Three and Four-Dimensional Visualization and Analysis Approaches to Study Vertebrate Axial Elongation and Segmentation
12:59

Three and Four-Dimensional Visualization and Analysis Approaches to Study Vertebrate Axial Elongation and Segmentation

Published on: February 28, 2021

4.0K
Systematic Assessment of Mammalian Skull Specimens for Dental and Temporomandibular Joint Pathology
07:26

Systematic Assessment of Mammalian Skull Specimens for Dental and Temporomandibular Joint Pathology

Published on: August 22, 2022

1.7K

Area of Science:

  • Paleontology
  • Marine Biology
  • Evolutionary Biology

Background:

  • The Mesozoic Marine Revolution (MMR) significantly altered marine ecosystems and tetrapod evolution.
  • Ichthyosaurs, marine reptiles, evolved increasingly fish-like body plans during this period.
  • Skeletal pathologies can offer insights into the functional morphology and behavior of extinct animals.

Purpose of the Study:

  • To investigate skeletal pathologies in Middle Triassic and Early Jurassic ichthyosaurs.
  • To identify changes in pathology distribution and prevalence that may correlate with the MMR.
  • To infer functional and behavioral shifts in ichthyosaur evolution.

Main Methods:

  • Stratigraphically surveyed 200 Middle Triassic and Early Jurassic ichthyosaur specimens.
  • Documented and compared the type, distribution, and prevalence of skeletal pathologies.
  • Analyzed pathological bone locations in relation to ichthyosaur body size and geological age.

Main Results:

  • Skeletal pathologies were equally prevalent in both Triassic and Jurassic ichthyosaurs, primarily affecting individuals over 4 meters long.
  • Pathologies were concentrated in the hind limbs and tail of Triassic ichthyosaurs.
  • Jurassic ichthyosaurs showed a higher incidence of pathologies in the jaws, forelimbs, and ribcage.

Conclusions:

  • Pathology distribution in Triassic ichthyosaurs may reflect adaptations for primitive, eel-like swimming.
  • Increased rib fractures in Jurassic ichthyosaurs suggest behaviors like ramming or tail-striking, common in more fish-like marine tetrapods.
  • Skeletal pathologies provide evidence for structural modifications and behavioral changes in ichthyosaurs, coinciding with the MMR's ecological turnover.