When a bear obtains 70% of its food from a nearby stream, it spends 80% of its time at the stream; when it obtains 30% of its food from the stream, it spends 25%

of its time at the stream. When a cougar obtains 20% of its food in a particular canyon, it spends 35% of its time in that canyon; when it obtains 65% of its food from that canyon, it spends 80% of its time in the canyon. Which animal shows systematic evidence of bias? _______________.