Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

The Fossil Record

The Fossil Record

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...

Cranial Bones: Superior and Posterior View

Cranial Bones: Superior and Posterior View

The superior view of the cranium shows the frontal and paired parietal bones.
The frontal bone is the single bone that forms the forehead. At its anterior midline, between the eyebrows, there is a slight depression called the glabella. The frontal bone also forms the supraorbital margin of the orbit. Near the middle of this margin is the supraorbital foramen, the opening that provides passage for a sensory nerve to the forehead. The frontal bone is thickened just above each supraorbital margin,...

Cranial Bones: Lateral View

Cranial Bones: Lateral View

The lateral view of the cranium is dominated by temporal, sphenoid, and ethmoid bones.
The temporal bone forms the lower lateral side of the skull. The temporal bone is subdivided into several regions. The flattened upper portion is the squamous portion of the temporal bone. Below this area and projecting anteriorly is the zygomatic process of the temporal bone, which forms the posterior portion of the zygomatic arch. Posteriorly is the mastoid portion of the temporal bone. Projecting...

Osmoregulation in Fishes

Osmoregulation in Fishes

When cells are placed in a hypotonic (low-salt) fluid, they can swell and burst. Meanwhile, cells in a hypertonic solution—with a higher salt concentration—can shrivel and die. How do fish cells avoid these gruesome fates in hypotonic freshwater or hypertonic seawater environments?

Tooth Anatomy

Tooth Anatomy

The human tooth enables us to eat a variety of foods, speak clearly, and even aid in shaping our faces. Teeth are composed of various elements that work together. Here's a detailed look at the anatomy of a human tooth.
The Crown, Neck, and Root
The visible part of the tooth is referred to as the crown. It's covered by enamel, the hardest substance in the human body. The crown is uniquely shaped for each type of tooth, allowing for different functions such as cutting, tearing, or...

Phylogeny

Phylogeny

Phylogeny is concerned with the evolutionary diversification of organisms or groups of organisms. A group of organisms with a name is called a taxon (singular). Taxa (plural) can span different levels of the evolutionary hierarchy. For instance, the group containing all birds is a taxon (comprising the class Aves), and the group of all species of daisies (the genus Bellis) is a taxon. Phylogenies can likewise include just one genus (i.e., depict species relationships) or span an entire kingdom.

You might also read

Related Articles

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

Sort by

Same author

The contingent advantage of photosymbiosis in coral evolution.

Proceedings of the National Academy of Sciences of the United States of America·2026

Same author

A ∼0.5 Myr perturbation of carbon and mercury cycles during the Middle Triassic biotic radiation.

Science advances·2026

Same author

Rapid riparian ecosystem recovery in low-latitudinal North China following the end-Permian mass extinction.

eLife·2026

Same author

Complex marine ecological response during the Eocene-Oligocene revealed by global foraminiferal record.

Nature communications·2026

Same author

Trophic ecology outweighed intrinsic constraints in shaping skull evolution of carnivorous Permian synapsids.

Communications biology·2026

Same author

Author Correction: The oldest known lepidosaur and origins of lepidosaur feeding adaptations.

Nature·2025

Search research articles

Related Experiment Video

Updated: Aug 19, 2025

Dissection and Flat-mounting of the Threespine Stickleback Branchial Skeleton

Dissection and Flat-mounting of the Threespine Stickleback Branchial Skeleton

Published on: May 7, 2016

A Triassic crown squamate.

David I Whiteside^1,2, Sofía A V Chambi-Trowell¹, Michael J Benton¹

¹School of Earth Sciences, University of Bristol, Bristol, BS8 1RJ, UK.

Science Advances

|December 2, 2022

Summary

This summary is machine-generated.

Fossil lizard discovery in England reveals squamate reptile origins are older than previously believed. This finding aids understanding of modern reptile evolution and biodiversity science.

More Related Videos

In Situ Hybridization Techniques for Paraffin-Embedded Adult Coral Samples

In Situ Hybridization Techniques for Paraffin-Embedded Adult Coral Samples

Published on: August 31, 2018

Assessing Species-specific Contributions To Craniofacial Development Using Quail-duck Chimeras

Assessing Species-specific Contributions To Craniofacial Development Using Quail-duck Chimeras

Published on: May 31, 2014

Related Experiment Videos

Last Updated: Aug 19, 2025

Dissection and Flat-mounting of the Threespine Stickleback Branchial Skeleton

Dissection and Flat-mounting of the Threespine Stickleback Branchial Skeleton

Published on: May 7, 2016

In Situ Hybridization Techniques for Paraffin-Embedded Adult Coral Samples

In Situ Hybridization Techniques for Paraffin-Embedded Adult Coral Samples

Published on: August 31, 2018

Assessing Species-specific Contributions To Craniofacial Development Using Quail-duck Chimeras

Assessing Species-specific Contributions To Craniofacial Development Using Quail-duck Chimeras

Published on: May 31, 2014

Area of Science:

Paleontology
Evolutionary Biology
Vertebrate Zoology

Background:

Mammal and bird origins are understood, but squamate (lizard, snake) evolution remains unclear.
Squamates are key living vertebrates, crucial for biodiversity science.

Purpose of the Study:

To investigate the obscure evolutionary roots of squamates.
To provide new insights into the origins and diversification of modern-type lizards.

Main Methods:

Discovery and analysis of a Late Triassic fossil lizard from England.
Examination of a partial skeleton, skull, and mandibles.
Identification of unique squamate traits and shared apomorphies.

Main Results:

A modern-type lizard fossil from 202 million years ago (Ma) was discovered.
The fossil exhibits at least 15 unique squamate traits and shared unidentatan and anguimorph apomorphies.
Revised dating suggests crown Squamata originated much earlier than previously thought.

Conclusions:

The new fossil discovery significantly pushes back the origin of crown Squamata.
Modern-type squamate diversification is linked to the Carnian Pluvial Episode (232 Ma ago).
Understanding squamate evolution is vital for broader vertebrate biodiversity science.