modelorganism

Model organisms are non-human species that are extensively studied to understand fundamental biological processes. Findings in model organisms are often applicable to other species, including humans, because many biological pathways are conserved across life. Model organisms are chosen for practical advantages such as short generation times, small size, ease of cultivation, well-annotated genomes, and a broad toolkit for genetic manipulation and experimental reproduction.

Common model organisms include Escherichia coli (a bacterium), Saccharomyces cerevisiae (baker's yeast), Caenorhabditis elegans (a nematode), Drosophila melanogaster (the fruit fly), Mus musculus (the house mouse), Rattus norvegicus (the rat), Arabidopsis thaliana (a plant), and Danio rerio (zebrafish). Each has contributed to major advances: yeast and bacteria in cell-cycle and metabolism studies; C. elegans and Drosophila in developmental genetics and neural circuits; mice and zebrafish in vertebrate development and disease models; Arabidopsis in plant biology and genetics.

Applications of model organisms span genetics, development, neuroscience, immunology, physiology, and disease research. They enable controlled experiments, high-throughput screening, and rapid testing of genetic and pharmacological interventions. Advances rely on organized community resources, including genome sequences, mutant or gene-editing libraries, and standardized experimental protocols.

Limitations include the risk that findings do not translate directly to humans due to evolutionary distance, missing organ systems, or species-specific pathways. Ethical considerations apply, particularly for vertebrate models. Thus, researchers often use multiple models to cross-validate results and to balance simplicity with biological relevance.