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My Ears and Toes are Cold

It’s curious that the huge ears of rabbits seem able to tolerate the adverse effects of winter better than our little human ears, which are so vulnerable to freezing.

Freezing of body parts is called frostbite. It can happen quickly in the extremities, such as ears, fingers and toes. The situation is serious because blood circulation is impaired. Blood is about ninety percent water. In very cold weather, ice crystals can form in the blood stream. Since water expands when it forms ice, freezing can destroy cells, damage tissue, and cause loss of circulation. This can lead to irreversible consequences and dead tissue. A frostbitten area becomes pale and numb when frozen.

Animals have a number of protective mechanisms against the cold. An insulating cover of fur, fat or feathers minimizes heat loss. In addition, many animals develop a natural antifreeze in their blood. Birds’ feet never freeze, because they have no blood flow in them.

In many animals, a rapid heart beat helps the blood stay warm, and minimizes the possibility of freezing by keeping the blood moving rapidly. While your pulse rate is, say, seventy beats a minute, a rabbit’s pulse rate might be two hundred beats a minute. A mouse’s heartbeat is around four hundred beats a minute. So next time you’re out in the cold, protect those ears and toes.

It is always interesting to look at the way different creatures are compensated for their weaknesses. Beyond “antifreeze” in the blood of mammals to keep their extremities from freezing, we find several other examples: • Hibernation for those animals whose food supply is not available during harsh winter months.

• Camouflage for creatures which cannot outrun predators, and for those who depend on stalking to get close to prey.

• Sharp quills, fins, spines, or irritating smells, for some other slow or ungainly creatures.

• Speed adaptations for animals which must run down their prey.

• Especially keen sight for creatures which must locate their prey from a great distance.

• Sonar, sophisticated communications systems, and specializations of many different kinds all help keep nature in balance.

Humans are compensated for their many physical limitations and weaknesses with intellectual and emotional advantages, which allow us as naked, relatively slow, land-bound, ill-defended creatures to live in cold climates, avoid faster predators, use water for transportation and design and devise weapons to use against sharp teeth and claws.

One of the great conundrums facing us is where the specialization of different species originated? Some specializations only make sense in light of the specialization of other species. The diversification in nature is mind boggling. There seems to be art involved. We can all identify certain physical advantages yet these are carefully balanced among the creatures that inhabit the planet.

If it is advantageous for mammals to fly, why are bats the only ones that do? Wouldn’t the keen eyesight of a hawk help his prey to keep out of his way? If sonar is handy for whales and dolphins, wouldn’t it be useful for all other marine creatures as well?

The problem is that many of these compensations have to be fully-functioning to be any use at all. This suggests that there is an element of intelligence behind the design and creation of each creature. A simple “God made it” answer is not very satisfying answer to materialists, but a simple “It just evolved” answer doesn’t answer all the questions either.

David Humphreys and Ron Hughes