Similar observations exist for other species such as the genus Leucaena in which human-mediated sympatry in Mesoamerican “backyard gardens” of previously separated wild taxa, prolonged predomestication cultivation followed by spontaneous hybridization led to the emergence of different domesticated species.

Both were pipped to the post in 1888 by the German physicist Heinrich Hertz, a student of Hermann von Helmholtz (himself one of the towering figures of nineteenth-century German physics) who announced to the world that he had found a way of propagating and detecting these long-sought-for electromagnetic waves.

When we have a chance to demo the product the response has been uniformally positive.

The arcual measure of an angle is that in which the unit angle has its measuring arc equal to the radius of the circle.