The body temperature of a turtle changes with the temperature of its environment, making cold-blooded a misnomer. The blood temperature of a turtle sitting on a rock in full sunshine may be quite warm. Its dependence on outside temperatures, or ectothermy (ecto= outside; thermy= temperature) compels turtles to seek places with desirable temperatures. Every turtle species has a preferred temperature range for digestion and other metabolic processes. To get within range, some turtles need to sit in the sun (bask) for at least part of the day. Basking also dries out a turtle's shell, which might inhibit growth of algae or drive away other parasites that need moisture. A typical pattern is to bask in the morning until its body temperature gets high enough for a turtle to be active. Time spent seeking food (foraging) competes with basking. A turtle often alternates basking with foraging during the daylight hours.