Some articles on evolutionary studies:

Early Man Couldn’t Stomach Milk.
Chimps Use Spears To Hunt Mammals.
Chimp “Stone Age” Finds Are Earliest Nonhuman Ape Tools.

GORILLAS USING TOOLS. It is the first documented use of tools among wild gorillas. Now all the great apes are known to use tools. Evidence that all great apes use tools adds insight to human evolution. It suggests that tool use emerged in primates before humans split from the great apes. Tool-use was once thought a distinguishing characteristic of humans.

Though tool use is likely infrequent among gorillas, the new evidence provides insight to how gorillas see the world and interact with their environment, Breuer said.

“The most fascinating thing about this observation is the similarity [to humans] with which the gorillas solve the problems in this particular habitat,” he said. “If you or me want to cross a swamp, we use the same solutions as gorillas.” [from the NGS article]

Here is an Interesting article about dolphins and whales. Researchers just discovered that newborns and their mothers actually do not sleep at all during their first month. Also, female bottlenose dolpins have been discovered to teach their daughters to use marine sponges in order to protect their snouts while searching for prey on the rocky ocean floor. Since this is only passed on from mother to daughter, this is the first known example of tool-related culture in cetaceans. Read that article here.