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

What is Evolutionary History?

What is Evolutionary History?

Scientists record evolutionary history by analyzing fossil, morphological, and genetic data. The fossil record documents the history of life on Earth and provides evidence for evolution. However, both fossil and living organisms offer evidence that outlines Earth’s evolutionary history.

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.

Eukaryotic Evolution

Eukaryotic Evolution

The endosymbiont theory is the most widely accepted theory of eukaryotic evolution; however, its progression is still somewhat debated. According to the nucleus-first hypothesis, the ancestral prokaryote first evolved a membrane to enclose DNA and form the nucleus. Conversely, the mitochondria-first hypothesis suggests that the nucleus was formed after endosymbiosis of mitochondria.
Contrary to the endosymbiont theory, the eukaryote-first hypothesis proposes that the simpler prokaryotic and...

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.

The Tree of Life - Bacteria, Archaea, Eukaryotes

The Tree of Life - Bacteria, Archaea, Eukaryotes

The “tree of life” describes the evolution of life and the evolutionary relationships between organisms. The root of the tree is the common ancestor to all life on Earth. All other species radiate from this point, much like the branches of a tree. The numerous tips of these branches on the tree of life represent every living, or extant, species. Extinct species, which are species that no longer exist, can be found towards the center of the tree. Currently, these organisms, both...

The Colonization of Land

The Colonization of Land

Changes in the environment of the early Earth drove the evolution of organisms. As prokaryotic organisms in the oceans began to photosynthesize, they produced oxygen. Eventually, oxygen saturated the oceans and entered the air, resulting in an increase in atmospheric oxygen concentration, known as the oxygen revolution approximately 2.3 billion years ago. Therefore, organisms that could use oxygen for cellular respiration had an advantage. More than 1.5 years ago, eukaryotic cells and...

You might also read

Related Articles

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

Sort by

Same author

Hunting ecology predicts eye arrangements in the modular visual system of spiders.

Current biology : CB·2026

Same author

Exploring the Genotype-to-Phenotype Map Using Quantifiable Patterns in Metazoan Genomic and Morphological Data.

The American naturalist·2026

Same author

Community hydrodynamics created ecological opportunity in Ediacaran shallow marine ecosystems.

PNAS nexus·2025

Same author

But the Clock, Tick-Tock: An Empirical Case Study Highlights the Preeminence of Relaxed Clock Models in Total-Evidence Dating.

Systematic biology·2025

Same author

A new Cambrian stem-group echinoderm reveals the evolution of the anteroposterior axis.

Current biology : CB·2025

Same author

Museum 'dark data' show variable impacts on deep-time biogeographic and evolutionary history.

Proceedings. Biological sciences·2025

Search research articles

Related Experiment Video

Updated: Dec 25, 2025

Ablation of a Single Cell From Eight-cell Embryos of the Amphipod Crustacean Parhyale hawaiensis

Ablation of a Single Cell From Eight-cell Embryos of the Amphipod Crustacean Parhyale hawaiensis

Published on: March 16, 2014

Evolution and Development at the Origin of a Phylum.

Bradley Deline¹, Jeffrey R Thompson², Nicholas S Smith³

¹Department of Geoscience, University of West Georgia, Carrollton, GA 30118, USA.

Current Biology : CB

|March 21, 2020

Summary

This summary is machine-generated.

Evolving echinoderm body plans show gradual divergence and amplified distinctiveness due to extinctions and convergence. Key traits remained flexible, allowing for continued evolutionary innovation in early animal evolution.

Keywords:

Body Plan Cambrian Explosion Disparity Echinodermata Extinction Gene Regulatory Networks Macroevolution Morphologic Innovation Morphology Phylomorphospace

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

Genotyping of Sea Anemone during Early Development

Genotyping of Sea Anemone during Early Development

Published on: May 13, 2019

Related Experiment Videos

Last Updated: Dec 25, 2025

Ablation of a Single Cell From Eight-cell Embryos of the Amphipod Crustacean Parhyale hawaiensis

Ablation of a Single Cell From Eight-cell Embryos of the Amphipod Crustacean Parhyale hawaiensis

Published on: March 16, 2014

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

Genotyping of Sea Anemone during Early Development

Genotyping of Sea Anemone during Early Development

Published on: May 13, 2019

Area of Science:

Evolutionary biology
Paleontology
Developmental biology

Background:

Understanding the origin and diversification of phyla requires quantifying morphological evolution.
The early Paleozoic was a critical period for the establishment of major animal body plans.

Purpose of the Study:

To characterize the radiation and establishment of echinoderm body plans during the early Paleozoic.
To investigate the fixation and flexibility of higher-order morphological characters in early echinoderm evolution.

Main Methods:

Construction of a hierarchical morphological character matrix.
Analysis of evolutionary patterns of echinoderm body plans during the Cambrian and Ordovician periods.

Main Results:

Subphylum-level echinoderm clades diverged gradually through the Cambrian.
Body plan distinctiveness was amplified by the extinction of transitional forms and obscured by convergent evolution in the Ordovician.
Higher-order characters defining body plans were not fixed at the phylum's origin, indicating flexibility.

Conclusions:

Morphological evolution in early echinoderms was characterized by gradual divergence and later amplification of distinctiveness.
The flexibility of key morphological characters facilitated ongoing evolutionary innovation within echinoderm clades.
Findings challenge hypotheses about fixed developmental processes governing early animal evolution.