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Perhaps of interest to some (but was never a Field Guide)...
"Dogs have been our companions for thousands of years. This long
allegiance and our preferences for dogs with certain traits have led to
an unmatched degree of morphological variation and an opportunity for
geneticists to unravel how genes interact with selection to shape
phenotypes. Recent work in this area has revealed much about the genes
underlying specific traits, such as coat color, foreshortened limbs, and
hairlessness. Boyko /et al./ have examined variation at over 60,000
single-nucleotide polymorphisms in 80 dog breeds, African village dogs,
and wolves. Interestingly, they found that the majority of variation
among breeds was generated by just a few genomic regions of large
effect. For example, they identified only six regions associated with
body size, and ear floppiness was associated with just a single region.
They hypothesize that the small number of regions controlling such a
large degree of variation is probably due to the repeated bottlenecks
dogs went through in their evolution, first when they were domesticated
and then during breed development. Genetic diversity measures support
this hypothesis, as all breeds displayed much lower genetic diversity
than either wolves or village dogs. --/PLoS Biol./ *8*, e1000451 (2010)."
A genome selected to be morphologically plastic, Fido is... albeit
This could happen "naturally" as well. A basal genome that is driven by
species recognition (see Horner and Padian -- "The evolution of ‘bizarre
structures’ in dinosaurs: biomechanics, sexual selection, social
selection or species recognition?" in J. Zoo.) would benefit from such
plasticity, especially in areas that enable visual differentiation, in
the sense that a ready path to morphological diversification and
subsequent speciation could further habitat exploitation. I propose the
resulting 'clutch' of related species be called a 'genus' ... er, never
I suggest (again) that imprinting is a mechanism in extant animals which
both highlights the importance of species recognition as a tactic and
levers aspiring young critters into a morphologically exaggerated future
-- as in, "Wow, you look even more like Mama than Mama does."
If the above is correct, the implication is that at least transitory
early parental presence is fundamental, perhaps even necessary, to the
creation of "bizarre" and diverse-but-related taxa, at least within
larger vertebrates. Sexual selection apparently does NOT need an 'early
look' at conspecifics to function, but obviously could 'co-exist' w/
recognition w/in a species...