why elephants have big ears

Lavers, Chris. Why Elephants Have Big Ears: Understanding patterns of Life on Earth. New York: St. Martin’s Press, 2000.

In Chris Lavers’ book, he answers many questions of the natural world by explaining basic biology and theories of evolution with abundant interesting examples. The title asks a thought-provoking question that becomes a great starting point to explore the reason why do animals look like what they are.

At this point, I have only finished the first 2 chapters and have attained enough useful information to start thinking about designing my characters through the most anatomically logical approach. Some aspects are:

Larger the animal = larger the volume

Larger the animal = larger the surface area

But, increase in volume > increase in surface area

1. Size/weight of body vs. thickness and structure of legs

2. Structure of legs vs. need (to run)

3. Size/weight of head vs. thickness and length of neck

4. Size/weight of body vs. amount of heat generated within animals: Larger the animal more heat is generated.

5. Warm blooded animals: size/weight of body vs. rate at which cells produce heat – larger the animal slower the rate, but not enough to balance temperature

6. Size/weight of body vs. surface area for heat to escape, smaller the animal, heat faster heat escapes

7. Size/weight of body vs. amount of fur- larger the animal, more heat generated and less fur needed

8. Size/weight of body vs. rate of heart beat – smaller the animal, faster the heart beats

9. Size/weight of body vs. relative size of heart – smaller the animal, larger the heart-size relatively

10. Size/weight of body vs. relative amount of food consumption – smaller the animal, more food consumption relatively

Summary:

Large animals grew thick legs and thick necks to hold the large body and head against gravity. Because they are large in volume, more heat is generated, surpassing the amount of heat that can escape through the surface area. Thus, they have other alternatives to balance their body temperature. Their cells produce heat at a slower rate. They have either less or no fur at all. They need to consume less food.

Small animals like gazelles developed thin legs and strong, light muscles to run away from their predators. Their hind legs have the same effect of a permanent sprinter’s crouch. Small animals like shrews have small bodies but relatively large surface areas for heat to escape. Thus, they need to maintain their body temperature by consume much more food, have faster heart beat, and have a larger heart in proportion to increase blood flow through their entire body.