But had not man accelerated the process, they would indeed have taken millions of years to produce just a few breeds and be separated in sequential layers by tens of millions of years.
Unsupported nonsense. I posted this example in another thread...
Speciation in real time
The Central European blackcap spends its summers in Germany and Austria and, until the 1960s, had spent its winters in balmy Spain. About 50 years ago, however, backyard bird feeding became popular in Britain. With a ready supply of food waiting for them in Britain, blackcaps that happened to carry genes that caused them to migrate northwest, instead of southwest to Spain, were able to survive and return to their summer breeding grounds in central Europe. Over time, the proportion of the population carrying northwest-migrating genes has increased. Today, about 10% of the population winters in Britain instead of Spain.
This change in migration pattern has led to a shift in mate availability. The northwest route is shorter than the southwest route, so the northwest-migrating birds get back to Germany sooner each summer. Since blackcaps choose a mate for the season when they arrive at the breeding grounds, the birds tend to mate with others that follow the same migration route.
In December of 2009, researchers from Germany and Canada confirmed that these migration and mating shifts have led to subtle differences between the two parts of the population. The splinter group has evolved rounder wings and narrower, longer beaks than their southward-flying brethren. The researchers hypothesize that both of these traits evolved via natural selection. Pointier wings are favored in birds that must travel longer distances, and rounder wings, which increase maneuverability, are favored when distance is less of an issue — as it is for the northwest migrators. Changes in beak size may be related to the food available to each sub-population: fruit for birds wintering in Spain and seeds and suet from garden feeders for birds wintering in Britain. The northwest migrators' narrower, longer beaks may allow them to better take advantage of all the different sorts of foods they wind up eating in the course of a year. These differences have evolved in just 30 generations and could signify the beginning of a speciation event.
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