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

Types of Selection

Types of Selection

Natural selection influences the frequencies of particular alleles and phenotypes within populations in several different ways. Primarily, natural selection can be directional, stabilizing, or disruptive. Directional selection favors one extreme trait and shifts the population towards that phenotype while selecting against individuals displaying alternate traits. Stabilizing selection favors an intermediate trait with a narrow range of variation. Deviation from the optimal phenotype towards an...

Migration

Migration

Migration is long-range, seasonal movement from one region or habitat to another. This common strategy, carried out by many different organisms around the world, is an adaptive response that typically corresponds to changes in an organism’s environment, like resource availability or climate. Migrations can involve huge groups of thousands of animals as well as single individuals traveling alone and can range from thousands of kilometers to just a few hundred meters.

Diversity of Protists II

Diversity of Protists II

Alveolates are a group of organisms recognized by the presence of alveoli, which are cytoplasmic sacs located beneath the cell membrane. While their function remains uncertain, alveoli may help regulate water balance by controlling how much water enters and leaves the cell. In dinoflagellates, these structures may serve as armor plates. There are three major types of alveolates: ciliates, which move using cilia; dinoflagellates, which use flagella for movement; and apicomplexans, which are...

Malaria

Malaria

Malaria pathogenesis in humans reflects a delicate interplay between parasite biology and host response. Clinical illness reflects a host’s immune response to the parasite’s asexual replication cycle, which is often asymptomatic in individuals with partial immunity. From the parasite's perspective, transmission between mosquito and human with minimal host pathology is evolutionarily advantageous. Among the six Plasmodium species infecting humans, P. falciparum and P. vivax dominate in global...

Symbiosis

Symbiosis

Symbiotic relationships are long-term, close interactions between individuals of different species that affect the distribution and abundance of those species. When a relationship is beneficial to both species, this is called mutualism. When the relationship is beneficial to one species but neither beneficial nor harmful to the other species, this is called commensalism. When one organism is harmed to benefit another, the relationship is known as parasitism. These types of relationships often...

Frequency-dependent Selection

Frequency-dependent Selection

When the fitness of a trait is influenced by how common it is (i.e., its frequency) relative to different traits within a population, this is referred to as frequency-dependent selection. Frequency-dependent selection may occur between species or within a single species. This type of selection can either be positive—with more common phenotypes having higher fitness—or negative, with rarer phenotypes conferring increased fitness.Positive Frequency-Dependent SelectionIn positive...

You might also read

Related Articles

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

Sort by

Same author

Observation of the Radiative Decay D_{s0}^{}(2317)^{+}→D_{s}^{+}γ.

Physical review letters·2026

Same author

First Search for B→X_{s}νν[over ¯] Decays.

Physical review letters·2026

Same author

Search for Feebly Interacting Particles in B Decays with Missing Energy at Belle.

Physical review letters·2026

Same author

Pneumoperitoneum in dis-eases and traumas of the upper part of the digestive tract - an overview of current knowledge and clinical context.

Rozhledy v chirurgii : mesicnik Ceskoslovenske chirurgicke spolecnosti·2026

Same author

Rare causes of pneumoperitoneum.

Rozhledy v chirurgii : mesicnik Ceskoslovenske chirurgicke spolecnosti·2026

Same author

Deep molecular profiling of biliary tract cancer uncovers novel biological mechanisms and therapeutic opportunities.

ESMO open·2026

Search research articles

Related Experiment Video

Updated: Jul 19, 2026

Visually Sexing Loggerhead Shrike (Lanius Ludovicianus) Using Plumage Coloration and Pattern

Visually Sexing Loggerhead Shrike (Lanius Ludovicianus) Using Plumage Coloration and Pattern

Published on: March 8, 2020

Seasonal morphological variations in bird schistosomes.

C Bayssade-Dufour¹, D Jouet, J Rudolfova

¹USM 602, Biologie parasitaire, Systématique et Evolution, MNHN, 61, rue Buffon,75231 Paris, France.

Parasite (Paris, France)

|September 30, 2006

Summary

This study investigated schistosomes in French wildfowl, finding morphological variations in Bilharziella and Dendritobilharzia. DNA analysis confirmed single species for each genus, Bilharziella polonica and Dendritobilharzia, despite observed differences.

More Related Videos

Cercarial Transformation and in vitro Cultivation of Schistosoma mansoni Schistosomules

Cercarial Transformation and in vitro Cultivation of Schistosoma mansoni Schistosomules

Published on: August 16, 2011

Mass Isolation and In Vitro Cultivation of Intramolluscan Stages of the Human Blood Fluke Schistosoma Mansoni

Mass Isolation and In Vitro Cultivation of Intramolluscan Stages of the Human Blood Fluke Schistosoma Mansoni

Published on: January 14, 2018

Related Experiment Videos

Last Updated: Jul 19, 2026

Visually Sexing Loggerhead Shrike (Lanius Ludovicianus) Using Plumage Coloration and Pattern

Visually Sexing Loggerhead Shrike (Lanius Ludovicianus) Using Plumage Coloration and Pattern

Published on: March 8, 2020

Cercarial Transformation and in vitro Cultivation of Schistosoma mansoni Schistosomules

Cercarial Transformation and in vitro Cultivation of Schistosoma mansoni Schistosomules

Published on: August 16, 2011

Mass Isolation and In Vitro Cultivation of Intramolluscan Stages of the Human Blood Fluke Schistosoma Mansoni

Mass Isolation and In Vitro Cultivation of Intramolluscan Stages of the Human Blood Fluke Schistosoma Mansoni

Published on: January 14, 2018

Area of Science:

Parasitology
Systematic Zoology
Molecular Biology

Background:

Schistosomes are parasitic flatworms with complex life cycles.
The genera Bilharziella and Dendritobilharzia are known parasites of wildfowl.
Understanding schistosome diversity is crucial for host-parasite ecology.

Purpose of the Study:

To contribute to the systematic understanding of Bilharziella and Dendritobilharzia.
To investigate morphological variations within these schistosome genera in wildfowl.
To clarify species identification using molecular data.

Main Methods:

Necropsy of wildfowl (mallards, grey heron, mute swans) from Champagne-Ardenne, France.
Morphological examination of collected schistosomes, focusing on male and female reproductive systems and spination.
DNA sequencing for species-level identification and phylogenetic analysis.

Main Results:

Morphological variations were observed in Bilharziella, suggesting multiple species, but DNA analysis confirmed them as Bilharziella polonica.
Dendritobilharzia samples exhibited morphological differences from the type species D. pulverulenta, yet molecular analysis confirmed their identity.
Parasitism by Bilharziella was found in mallards, grey herons, and mute swans, while Dendritobilharzia was found in a mute swan.

Conclusions:

Morphological variations in Bilharziella and Dendritobilharzia are likely influenced by host factors, season, and parasite age, not indicative of distinct species.
The systematic definitions of the genera Bilharziella and Dendritobilharzia were amended based on the findings.
Molecular data is essential for accurate schistosome species identification, complementing traditional morphology.