Related Experiment Video
Updated: Mar 15, 2026
12:37
Pharmacologic Induction of Epidermal Melanin and Protection Against Sunburn in a Humanized Mouse Model
Published on: September 7, 2013
18.9K
Ecological Genetics: A Key Gene for Mimicry and Melanism
James Mallet1, Hopi E Hoekstra2
1Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA.
Current Biology : CB
|September 14, 2016
Summary
Mimicry in butterflies and melanism in moths, classic examples of natural selection, are surprisingly controlled by the same gene, cortex. This genetic finding reveals a shared mechanism underlying distinct evolutionary adaptations in Lepidoptera.
Area of Science:
- Evolutionary biology
- Genetics
- Animal behavior
Background:
- Mimicry and melanism in Lepidoptera (butterflies and moths) are historically significant examples demonstrating natural selection.
- Previous research established these phenomena as key cases of adaptive evolution.
Purpose of the Study:
- To investigate the genetic basis of mimicry in Heliconius butterflies and melanism in peppered moths.
- To determine if shared genetic mechanisms underlie these distinct evolutionary traits.
Main Methods:
- Genetic analysis of Heliconius butterflies and peppered moths.
- Comparative genomic studies to identify shared genes.
Main Results:
- Genetic analysis revealed that the gene 'cortex' controls both mimicry in Heliconius butterflies and melanism in peppered moths.
- Identified the cortex gene as a crucial genetic locus for distinct adaptive traits in Lepidoptera.
Conclusions:
- The cortex gene plays a pivotal role in the evolution of both mimicry and melanism.
- This finding provides a surprising genetic link between two major forms of natural selection in Lepidoptera.
Related Concept Videos
01:39Epistasis
51.0K
In addition to multiple alleles at the same locus influencing traits, numerous genes or alleles at different locations may interact and influence phenotypes in a phenomenon called epistasis. For example, rabbit fur can be black or brown depending on whether the animal is homozygous dominant or heterozygous at a TYRP1 locus. However, if the rabbit is also homozygous recessive at a locus on the tyrosinase gene (TYR), it will have an unshaded coat that appears white, regardless of its TYRP1...
51.0K
01:09Epistasis Analysis
6.1K
Although Mendel chose seven unrelated traits in peas to study gene segregation, most traits involve multiple gene interactions that create a spectrum of phenotypes. When the interaction of various genes or alleles at different locations influences a phenotype, this is called epistasis. Epistasis often involves one gene masking or interfering with the expression of another (antagonistic epistasis). Epistasis often occurs when different genes are part of the same biochemical pathway. The...
6.1K
02:27Background and Environment Affect Phenotype
8.0K
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...
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...
8.0K
02:32Position-effect Variegation
7.2K
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.
7.2K
02:39Predator-Prey Interactions
22.1K
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.
22.1K
02:37Gene Duplication and Divergence
8.2K
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 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...
8.2K