A lthough the title leads with the question “What is a Basenji,” for this article I have chosen to steer away from using the term “Basenji” to label the native Congo Basin dog because that serves only to distract and confuse people who get hung up on something that is no more than a Westernized word. Yet, the information presented responds directly to this question. To begin, let’s step back and expand our understanding of natural selection pressures/processes and the isolation mechanisms/barriers that have regulated, and more importantly obstructed, gene flow over the past 2,000 years (not including the most recent 200 years) on the African continent. These powerful selection pressures include ethnicity (tribalism), culture, language, geography, technology, logistics, history, environment, etc. Broadly, this is the science of phylogeography; the study of processes that result in geographic distribution of distinct life forms. Let’s consider the geographic location of different biomes. A biome is simply any major ecological community of organisms, both plant and animal. Biomes are defined in terms of the entire biotic community of living organisms and their inter- relationships with their immediate environment. The map presented here illustrates the most distinct biomes on the African continent relevant to this topic. These biomes have a direct and significant impact on the resident biotic assemblage and the human lifestyles (including how dogs are routinely employed) that adapted to each region. The polygons represent some of the most obvious regional biomes on the continent: MD = desert south of the Mediterranean ; DG = Dahomey Gap ; EF = Equatorial old-growth primary Forest ; RV = east of the Rift Valley ; SA = Southern African countries. All aboriginal (earliest known) domestic dogs have a very similar basic physical appearance. This primitive canid body shape is known as the “long-term pariah morphotype” (LTPM). The LTPM silhouette is characterized by a wolf or fox-like appearance, with sharp-pointed, erect ears, a long, pointed muzzle and a long, sickle-shaped tail. This is the generalized form that is at the root of the domestic canine ancestry. Some people call this the “null” type because it is also the profile (outline) that modern canines revert back to when generations are left under the influence of natural processes breeding without human selection. Before humans intervened, the earliest dog ancestor diverged into populations of separate types based on natural selection (including the mechanisms identified above) and their success functioning in each biome. As these first domestic dogs migrated with humans, the primitive canine morphotype branched out across global landscapes and new, locally distinct types developed. Under the unique pressures of different environments, the distinct types stabilized as separate natural breeds. Over the past few thousand years, each geographically specific variety of dog (with a distinctive common gene pool, uniformity of type/ appearance, and consistent function) evolved from the basic, original LTPM form into a recognizable, geographic type. These divergent populations formed discrete breeds specific to their biome of origin. Often I read comments referring to dogs around the world that are “basenji- like” in that they have a common general primitive silhouette. What we are actually observing is the LTPM origin. It can be seen in all the primitive, aboriginal breeds: Australian Dingo, Congo Basin Basenji, New Guinea Singing Dog, Malaysian Dog, etc. But, “basenji-like” is not necessarily a Basenji. Given this background of breeds specific to their biome, we can identify a unique type (breed) that will be called “EFb” (i.e., Equatorial old-growth primary Forest breed) because it originated in the by Dr. Jo Thompson What is a Basenji? - The Modern Basenji - Worldwide - www.themodernbasenji.com | 10