Kids invariably have confusion regarding the meaning of the term: species. Emphasize, a species is a particular kind of living thing: plant, animal, microbe. It refers to all members/individuals of that kind the world over. The key feature that distinguishes one species from another is the ability to interbreed. Hence, the working definition of a species is: All those individuals that do or potentially can interbreed to produce viable offspring. If they can, they are one species; if they can’t, they are separate species. Usually, different species are quite visually different from one another as well. But this leads to confusion regarding breeds or varieties.
Plant and animal breeders, through the process of selective breeding, (see “selective breeding” on this site) have developed conspicuously different breeds of dogs, cats, horses, and all other domestic animals. However all breeds of such animals can still interbreed and produce viable offspring. Therefore, all breeds of a given animal still belong to the same species. This is why they are referred to as different breeds, not different species. The same applies to plants except the term variety is used in place of breed. Kids are generally awed by different breeds of given domestic animals and varieties of garden plants. Allow children to pick a domestic or farm animal and type into the browser: breeds of ______ images
Likewise have children pick a garden flower, vegetable, or fruit and type into your browser: varieties of _____ images
A further subdivision of a species is: population. A “population” is all the individuals of a given species living within a specified geographical area or some other characteristic that distinguishes them from other member of the same species. For example, rats are world wide. Thus one might speak specifically of the North American rat population.