Whale, whale, whale

As the length increases, volume increases much faster than the area.

" Surface area decreases for rounder objects." Why? 

"Surface-area-to-volume ratio decreases as the volume increases", this makes sense since area always increase lower than volume. ".  "So, by nau=tural selection, to get bigger means the surface-area-to-volume ratio and therefore decreases the rate f heat loss per unit volume, and to get spherical." 

"The sphere is the three-dimensional shape with the lowest surface-area-to-volume ratio.". "If you want to geenrate a lot of heat by having a large volume, but lose as little as possible, you'll be shperical - and the manatee is the most spherical mammal on Earth.