A
model organism is a
non-human species that is extensively studied to understand particular
biological phenomena, with the expectation that discoveries made in the organism model will provide insight into the workings of other organisms. Model organisms are
in vivo models and are widely used to research human
disease when
human experimentation would be unfeasible or
unethical. This strategy is made possible by the
common descent of all living organisms, and the conservation of
metabolic and
developmental pathways and
genetic material over the course of
evolution. Studying model organisms can be informative, but care must be taken when extrapolating from one organism to another.