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

Convergent Evolution

Convergent Evolution

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.

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.

Phylogenetic Trees

Phylogenetic Trees

Phylogenetic trees come in many forms. It matters in which sequence the organisms are arranged from the bottom to the top of the tree, but the branches can rotate at their nodes without altering the information. The lines connecting individual nodes can be straight, angled, or even curved.

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?

Gene Duplication and Divergence

Gene Duplication and Divergence

The seminal work of Ohno in 1970 popularized the idea of gene duplication and divergence. DNA sequence comparison studies reveal that a large portion of the genes in bacteria, archaebacteria, and eukaryotes was generated by gene duplication and divergence, indicating its critical role in evolution.
The duplicated copies of the gene are called Paralogs. Paralogs with similar sequences and functions form a gene family. Across several species, a large number of gene families are...

The Evidence for Evolution

The Evidence for Evolution

Genetic variations accumulating within populations over generations give rise to biological evolution. Evolutionary changes can result in the formation of novel varieties and entire new species. These changes are responsible for the diverse forms of life inhabiting the planet. The evidence for evolution suggests that all living organisms descended from common ancestors.

You might also read

Related Articles

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

Sort by

Same author

Largest Silurian fish illuminates the origin of osteichthyan characters.

Nature·2026

Same author

The oldest articulated bony fish from the early Silurian period.

Nature·2026

Same author

A dual respiratory and auditory function for the coelacanth lung.

Communications biology·2026

Same author

The shoulder girdle of early chondrichthyans grew by skeletal remodelling.

Biology letters·2025

Same author

Earliest amniote tracks recalibrate the timeline of tetrapod evolution.

Nature·2025

Same author

Re-examining the strangest early vertebrate.

National science review·2025

Search research articles

Related Experiment Video

Updated: Feb 17, 2026

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 Devonian tetrapod-like fish reveals substantial parallelism in stem tetrapod evolution.

Min Zhu^1,2, Per E Ahlberg³, Wen-Jin Zhao^4,5

¹Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, PO Box 643, Beijing, 100044, China. zhumin@ivpp.ac.cn.

Nature Ecology & Evolution

|November 30, 2017

Summary

A newly discovered Devonian fish fossil from China challenges the stable evolutionary tree of tetrapod ancestors. This finding reveals increased homoplasy and suggests greater underestimated ecological and biogeographical diversity within the tetrapod stem group.

More Related Videos

Microinjection for Transgenesis and Genome Editing in Threespine Sticklebacks

Microinjection for Transgenesis and Genome Editing in Threespine Sticklebacks

Published on: May 13, 2016

Dissection and Lateral Mounting of Zebrafish Embryos: Analysis of Spinal Cord Development

Dissection and Lateral Mounting of Zebrafish Embryos: Analysis of Spinal Cord Development

Published on: February 28, 2014

Related Experiment Videos

Last Updated: Feb 17, 2026

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

Microinjection for Transgenesis and Genome Editing in Threespine Sticklebacks

Microinjection for Transgenesis and Genome Editing in Threespine Sticklebacks

Published on: May 13, 2016

Dissection and Lateral Mounting of Zebrafish Embryos: Analysis of Spinal Cord Development

Dissection and Lateral Mounting of Zebrafish Embryos: Analysis of Spinal Cord Development

Published on: February 28, 2014

Area of Science:

Paleontology
Evolutionary Biology
Vertebrate Evolution

Background:

The tetrapod stem group fossils trace the transition of lobe-finned fishes to terrestrial vertebrates.
Phylogenetic stability in this group has been noted, incorporating discoveries like Tungsenia and Tiktaalik.

Purpose of the Study:

To describe a new large lobe-finned fish fossil from the Late Devonian of China.
To analyze its phylogenetic position and implications for tetrapod stem group evolution.

Main Methods:

Phylogenetic analysis using Bayesian inference and maximum parsimony.
Comparative morphological analysis of fossil specimens.

Main Results:

The new fossil exhibits a mix of basal rhizodont and derived elpistostegid/tetrapod-like features.
This mosaic challenges previous phylogenetic stability, indicating significant homoplasy.
Analyses suggest either extensive convergence or a closer relationship between rhizodonts and tetrapods.

Conclusions:

The tetrapod stem group exhibits greater homoplasy than previously recognized.
Ecological diversity and biogeographical provinciality within this group may have been underestimated.
This discovery necessitates a re-evaluation of early vertebrate terrestrialization.