Why are different breeds of dogs all considered the same species?
Full question: How come some similar animals are different species, while with domestic dogs, wildly dissimilar types are considered different breeds? — Z. Kornberg, Jerusalem Michael Bruford, a professor of biological sciences at Cardiff University in Wales, explains the thought process behind this seeming double standard. Scientists have been distinguishing between species on the basis of how they look, behave or live since recorded history began. However, two famous scientists stand out in terms of how we perceive species differences today: Carl Linnaeus, an 18th-century Swedish naturalist, and Charles Darwin. Linnaeus was the first person to formulate a single approach for describing species in a hierarchical manner according to their similarity, using his binomial nomenclature of genus followed by species (Homo sapiens, for instance). Darwin was among the first people, and certainly the most celebrated among them, to develop a credible theory on how species evolve (via natural se
