By Don Batten creation.com
Dogs can walk for long periods on snow and ice without their paws freezing, but how? Researchers recently studied the paws of four adult dogs and found that the arteries supplying blood to the pads had networks of numerous small veins closely associated with them.
This system acts as a counter-current heat exchanger. Warm blood comes to the paws via the arteries, and its heat is transferred to the veins closely associated with the arteries, which keeps the blood warm as it returns to the body.
This design is found in many different types of creatures, e.g. fish gills and squirrel tails. Designs such as this appear in a pattern called convergence—very similar designs found in completely unrelated contexts.
Evolutionists must say that this system evolved in different creatures independently. But this is an extremely weak explanation.
It makes much more sense that this testifies to a single designer of life who made life with unifying patterns that defy naturalistic explanations.
How dogs can walk on ice without freezing their paws, Physorg.com, 13 January 2012.
Functional anatomy of the footpad vasculature of dogs: scanning electron microsopy of vascular corrosion casts, Veterinary Dermatology 22(6):475–481, 2011.