The relatively low cost of the daguerreotype in the middle of the 19th century and the reduced sitting time for the subject, though still much longer than now, led to a general rise in the popularity of portrait photography over painted portraiture.
Fitch fur is the fur of the European Polecat, a member of the weasel family. Its texture is similar to mink, however its coloration differs from mink. While mink underfur is generally a single color with dark guard hair tips, fitch fur shows natural stripes and other color variations. add a comment.
Polar bears actually have transparent fur over black skin. Reflection of the sunlight from the densely packed transparent hairs makes polar bears seem to be white. The bears' black skin absorbs heat from the sun. The transparent fur is made up of hollow hairs called guard hairs. These air-filled guard hairs help transmit heat from the sunlight to the polar bear's black skin as a solar heat collector. In turn, the reflection stops the heat being lost from their black skin.