• Species
  Species
  In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
  
  : see mutualism, symbiosis
  Symbiosis
  Symbiosis is close and often long-term interaction between different biological species. In 1877 Bennett used the word symbiosis to describe the mutualistic relationship in lichens...
  
  
• organs
  Organ (anatomy)
  In biology, an organ is a collection of tissues joined in structural unit to serve a common function. Usually there is a main tissue and sporadic tissues . The main tissue is the one that is unique for the specific organ. For example, main tissue in the heart is the myocardium, while sporadic are...
  
  : see the evolution of the eye
  Evolution of the eye
  The evolution of the eye has been a subject of significant study, as a distinctive example of a homologous organ present in a wide variety of taxa. Certain components of the eye, such as the visual pigments, appear to have a common ancestry – that is, they evolved once, before the animals radiated...
  
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• Gene
  Gene
  A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...
  
  s or gene complexes: see Linkage disequilibrium
  Linkage disequilibrium
  In population genetics, linkage disequilibrium is the non-random association of alleles at two or more loci, not necessarily on the same chromosome. It is also referred to as to as gametic phase disequilibrium , or simply gametic disequilibrium...
  
  , epistasis
  Epistasis
  In genetics, epistasis is the phenomenon where the effects of one gene are modified by one or several other genes, which are sometimes called modifier genes. The gene whose phenotype is expressed is called epistatic, while the phenotype altered or suppressed is called hypostatic...
  
  

Examples

• The fig
  Ficus
  Ficus is a genus of about 850 species of woody trees, shrubs, vines, epiphytes, and hemiepiphyte in the family Moraceae. Collectively known as fig trees or figs, they are native throughout the tropics with a few species extending into the semi-warm temperate zone. The Common Fig Ficus is a genus of...
  
   and the fig wasp
  Fig wasp
  Fig wasps are wasps of the family Agaonidae which pollinate figs or are otherwise associated with figs, a coevolutional relationship that has been developing for at least 80 million years...
  
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• Myrmica sabuleti
  Myrmica sabuleti
  Myrmica sabuleti is a species of ant. The species is indigenous to Europe and most colonies are polygynous. The Large Blue butterfly caterpillar parasitically prey on the species as it hatchess on thyme buds and then tricks the ants into believing it is one of their own larvae, ants then carry it...
  
  and the Large Blue butterfly
  Large blue butterfly
  The Large Blue is a blue butterfly, that is resident in Europe and some parts of Asia. The butterfly was became extinct in the United Kingdom in 1979, but has since been reintroduced by conservationists...
  
  

External links

• Coadaptation entry in a dictionary on evolution
  Evolution
  Evolution is any change across successive generations in the heritable characteristics of biological populations. Evolutionary processes give rise to diversity at every level of biological organisation, including species, individual organisms and molecules such as DNA and proteins.Life on Earth...
  
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