Related Experiment Video

Updated: Jul 12, 2026

Visually Sexing Loggerhead Shrike (Lanius Ludovicianus) Using Plumage Coloration and Pattern
04:10

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

Published on: March 8, 2020

Realized reproductive success of polygynous red-winged blackbirds revealed by DNA markers

H L Gibbs, P J Weatherhead, P T Boag

    Science (New York, N.Y.)
    |December 7, 1990
    PubMed

    More Related Videos

    Who is Who? Non-invasive Methods to Individually Sex and Mark Altricial Chicks08:14

    Who is Who? Non-invasive Methods to Individually Sex and Mark Altricial Chicks

    Published on: May 24, 2014

    Probing the Limits of Egg Recognition Using Egg Rejection Experiments Along Phenotypic Gradients07:34

    Probing the Limits of Egg Recognition Using Egg Rejection Experiments Along Phenotypic Gradients

    Published on: August 22, 2018

    Related Concept Videos

    Mate Choice01:20

    Mate Choice

    Mate choice—the decision about whom to mate with—is a type of natural selection, since animals must reproduce to pass down their genes. Mate choice is also called intersexual selection because the behavior occurs between the sexes.
    Hardy-Weinberg Principle01:49

    Hardy-Weinberg Principle

    Diploid organisms have two alleles of each gene, one from each parent, in their somatic cells. Therefore, each individual contributes two alleles to the gene pool of the population. The gene pool of a population is the sum of every allele of all genes within that population and has some degree of variation. Genetic variation is typically expressed as a relative frequency, which is the percentage of the total population that has a given allele, genotype or phenotype.In the early 20th century,...
    Position-effect Variegation02:32

    Position-effect Variegation

    In 1928, a German botanist Emil Heitz observed the moss nuclei with a DNA binding dye. He observed that while some chromatin regions decondense and spread out in the interphase nucleus, others do not. He termed them euchromatin and heterochromatin, respectively. He proposed that the heterochromatin regions reflect a functionally inactive state of the genome. It was later confirmed that heterochromatin is transcriptionally repressed, and euchromatin is transcriptionally active chromatin.
    Understanding Species and Reproductive Barriers01:17

    Understanding Species and Reproductive Barriers

    A species is a group of organisms that interbreed and produce fertile offspring. Typically, individuals of the same species appear similar and share common characteristics due to their highly similar genomes. However, not all organisms that look alike are members of the same species. Various mechanisms keep most species discrete. While some mechanisms prevent reproductive behavior and fertilization (pre-zygotic isolation), others prevent the production of fertile offspring after mating has...
    Genetics of Speciation02:16

    Genetics of Speciation

    Speciation is the evolutionary process resulting in the formation of new, distinct species—groups of reproductively isolated populations.The genetics of speciation involves the different traits or isolating mechanisms preventing gene exchange, leading to reproductive isolation. Reproductive isolation can be due to reproductive barriers that have effects either before or after the formation of a zygote. Pre-zygotic mechanisms prevent fertilization from occurring, and post-zygotic mechanisms...
    Background and Environment Affect Phenotype02:27

    Background and Environment Affect Phenotype

    Although the genetic makeup of an organism plays a major role in determining the phenotype, there are also several environmental factors, such as temperature, oxygen availability, presence of mutagens, that can alter an organism’s phenotype.
    An example of how genetic background affects phenotype can be seen in horses. The Extension gene in horses is responsible for their coat color. A wild-type gene (EE) produces black pigment in the coat, while a mutant gene (ee) produces red pigment. A...