Speciation: Ernst Mayr Dobzhansky's Genetics and the Origin of
Species captivated biologists far beyond the confines of
genetics. In the mountains of New Guinea, an ornithologist named
Ernst Mayr (right) found the book to be an enormous inspiration.
Mayr specialized in discovering new species of birds and mapping
out their ranges. It is no easy matter determining exactly which
group of birds deserves the title of species. A bird of paradise
species might be recognizable by the color of its feathers, but
from place to place, it might have a huge amount of variation in
other traits on one mountain it might have an extravagantly long
tail while on another its tail would be cut square (below
right). Variation between populations Biologists typically tried
to bring order to this confusion by recognizing subspecies local
populations of a species that were distinct enough to warrant a
special label of their own. But Mayr saw that the subspecies
label was far from a perfect solution. In some cases, subspecies
weren't