For example, wolves can decide today that they need to hunt for food tomorrow. Some apes do, too, like chimpanzees. They have regular meal times, for example. Actually, after thinking about it, I'm not sure whether animals do think complex thoughts. USA I believe animals think because our neighbor's dog knows us and always likes to see us.
Dogs are smarter than other animals.
Our hermit crab only thinks about survival. I think animals think complex thoughts because they don't fit the standard definition of the difference between a human and an animal. According to the definition, if you point somewhere an animal will look at your hand, but a human will look where you are pointing. Wild animals think about what is safe for them to eat. Then again, animals do some things mostly by instinct.