What are model organisms?

Model organisms are non-human species that are used in research to help us understand specific areas of biology.

  • A model organism is a species that has been or can be widely studied in the lab – usually because it is easy to breed in a laboratory setting and has experimental advantages.
  • For example, yeast, the fruit fly and the mouse have taught scientists a lot about how different animals develop and what happens during the development of disease, leading to many new treatments.


What is a model organism?


  • Model organisms are non-human species that scientists use in the lab to investigate and understand biological processes.
  • They are usually organisms that are easy to maintain and breed in a laboratory setting.
  • For example, they may be bred in large numbers or have a very short time between being born and being able to reproduce, so several generations can be studied at once

What have we learned from using model organisms?  


some model organisms have similar genes and genomes to humans, enabling scientists to understand more about the relationship between genes and the products they code for.

Health and disease:

by manipulating the genome of organisms that are genetically like humans, scientists have learned more about different genetic conditions and diseases – leading to new treatments.


organisms with robust, easy-to-study embryos have revealed information about how animals including humans grow and develop.


organisms with an important position in the evolutionary tree have helped scientists understand how we have evolved from our ancestors.

Examples of model organisms used to study genetics:


  • Yeast (Saccharomyces cerevisiae)
  • Fruit fly (Drosophila melanogaster)
  • Nematode worm (Caenorhabditis elegans)
  • Western clawed frog (Xenopus tropicalis)
  • Mouse (Mus musculus)
  • Zebrafish (Danio rerio)


Animal use alternatives: the Three Rs


The ‘Three Rs’ are guiding principles for more ethical use and reduction of animals in research. They are:

  • Replacement (using alternatives where possible),
  • Reduction (designing experiments that minimise the number of an animal needed) and
  • Refinement (using methods that improve their welfare).

Find out about other organisms that have had their genomes sequenced here: