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

Distribution and Dispersion

Distribution and Dispersion

To understand intra-specific interactions in populations, scientists measure the spatial arrangement of species individuals. This geographic arrangement is known as the species distribution or dispersion. Highly territorial species exhibit a uniform distribution pattern, in which individuals are spaced at relatively equal distances from one another. Species that are highly tied to particular resources, such as food or shelter, tend to concentrate around those resources, and thus exhibit a...

Formation of Species

Formation of Species

Speciation describes the formation of one or more new species from one or sometimes multiple original species. The resulting species are discrete from the parent species, and barriers to reproduction will typically exist. There are two primary mechanisms, speciation with and without geographic isolation—allopatric and sympatric speciation, respectively.

Speciation Rates

Speciation Rates

Predator-Prey Interactions

Predator-Prey Interactions

Predators consume prey for energy. Predators that acquire prey and prey that avoid predation both increase their chances of survival and reproduction (i.e., fitness). Routine predator-prey interactions elicit mutual adaptations that improve predator offenses, such as claws, teeth, and speed, as well as prey defenses, including crypsis, aposematism, and mimicry. Thus, predator-prey interactions resemble an evolutionary arms race.

Channel Rhodopsins

Channel Rhodopsins

Most organisms use photoreceptors to sense and respond to light. Examples of photoreceptors include bacteriorhodopsins and bacteriophytochromes in some bacteria, phytochromes in plants, and rhodopsins in the photoreceptor cells of the vertebral retina. The light-sensitive property of these receptors is because of the bound chromophores, such as bilin in the phytochromes and retinal in the rhodopsins.
Rhodopsins belong to the family of cell surface proteins called G-protein coupled receptors,...

Diversity of Protists III

Diversity of Protists III

Rhizaria are a diverse group of unicellular protists characterized by their threadlike cytoplasmic extensions known as pseudopodia. These structures aid in both locomotion and feeding, giving Rhizaria an amoeboid appearance. Their amoeboid morphology once led to taxonomic confusion, but molecular phylogenetics has clarified their evolutionary placement and emphasized their shared use of pseudopodia despite divergent lineages.This clade comprises diverse lineages such as Chlorarachniophyta,...

You might also read

Related Articles

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

Sort by

Same author

Disentangling the genetic effects of refugial isolation and range expansion in a trans-continentally distributed species.

Heredity·2018

Same author

Specimen collection: an essential tool.

Science (New York, N.Y.)·2014

Same author

Ecological divergence and speciation between lemur (Eulemur) sister species in Madagascar.

Journal of evolutionary biology·2013

Same author

Detecting cryptic speciation in the widespread and morphologically conservative carpet chameleon (Furcifer lateralis) of Madagascar.

Journal of evolutionary biology·2012

Same author

Aligning conservation priorities across taxa in Madagascar with high-resolution planning tools.

Science (New York, N.Y.)·2008

Same author

Opening the black box: phylogenetics and morphological evolution of the Malagasy fossorial lizards of the subfamily "Scincinae".

Molecular phylogenetics and evolution·2004

Search research articles

Related Experiment Video

Updated: May 3, 2026

Multimodal Optical Microscopy Methods Reveal Polyp Tissue Morphology and Structure in Caribbean Reef Building Corals

Multimodal Optical Microscopy Methods Reveal Polyp Tissue Morphology and Structure in Caribbean Reef Building Corals

Published on: September 5, 2014

Chameleon radiation by oceanic dispersal.

C J Raxworthy¹, M R J Forstner, R A Nussbaum

¹American Museum of Natural History, Central Park West at 79th Street, New York, New York 10024-5192, USA. rax@amnh.edu

|February 15, 2002

Summary

Chameleon evolution was driven by oceanic dispersal from Madagascar, not ancient continental breakup. This study reveals multiple dispersal events shaped chameleon diversity across the Indian Ocean.

Area of Science:

* Historical biogeography and evolutionary biology.

Background:

* Vicariance methods, focusing on continental fragmentation (e.g., Gondwana breakup), dominate historical biogeography.
* Chameleons were previously thought to exhibit biogeographic patterns consistent with Gondwanan vicariance between Madagascar and Africa.

Purpose of the Study:

* To investigate the biogeographic history of chameleons using molecular and morphological data.
* To test the hypothesis of a vicariant origin versus a dispersal-driven radiation.

Main Methods:

* Phylogenetic analysis of 52 chameleon taxa using molecular and morphological evidence.
* Construction of an area cladogram to infer biogeographic history.

Main Results:

* Phylogenetic and area cladogram analyses do not support a simple vicariant history for chameleons.

More Related Videos

Assays to Detect UV-reflecting Structures and Determine their Importance in Mate Preference using the Sailfin Molly Poecilia latipinna

Assays to Detect UV-reflecting Structures and Determine their Importance in Mate Preference using the Sailfin Molly Poecilia latipinna

Published on: September 14, 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

Related Experiment Videos

Last Updated: May 3, 2026

Multimodal Optical Microscopy Methods Reveal Polyp Tissue Morphology and Structure in Caribbean Reef Building Corals

Multimodal Optical Microscopy Methods Reveal Polyp Tissue Morphology and Structure in Caribbean Reef Building Corals

Published on: September 5, 2014

Assays to Detect UV-reflecting Structures and Determine their Importance in Mate Preference using the Sailfin Molly Poecilia latipinna

Assays to Detect UV-reflecting Structures and Determine their Importance in Mate Preference using the Sailfin Molly Poecilia latipinna

Published on: September 14, 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

* Evidence points to oceanic dispersal as the primary driver of chameleon species radiation.

* A Madagascan origin is supported, with multiple dispersal events to Africa and Indian Ocean islands.

Conclusions:

* Oceanic dispersal, particularly 'out-of-Madagascar' events, facilitated chameleon speciation and radiation.
* The findings highlight the significant role of oceanic dispersal in terrestrial vertebrate evolution, challenging traditional vicariance-based models.