Difference Between Humans and Animals, Part IV

Perhaps I should change this series to the similarities between humans and animals. Either way, in the last couple of months I have been amazed at the intelligence of animals. Here are some more examples from the blog Not Exactly Rocket Science:

Chimps trump university students at memory task:

In 2004, Inoue and Matsuzawa started to teach 3 pairs of chimp mothers and children to play with numbers. One of the mums, Ai, was the first chimp to learn to use Arabic numerals to accurately number sets of real-life objects, but the other five had never done memory tasks involving numbers. Using at touch-screen computer, the duo eventually trained all the chimps to touch combinations of numbers from 1 to 9 in the right order.

When the youngsters reached their fifth birthday, Inoue and Matsuzawa taught them a more complicated task. When they touched the first digit, the others were replaced with white squares, and they had to rely on their memory to press the right sequence. The young chimps took to this task particularly well and amazingly, they finished the task more quickly than human adults.

Octopus can use a coconut shells as suit of armor:

Rat's can use metacognition:

Allison Foote and Jonathon Crystal searched for metacognition in rats by giving them a test that they could decline. If they passed, they received a big reward and if they failed, they got nothing. But the cunning part of their study lay in giving the rats a small reward if they declined the test. If they knew they were unlikely to succeed, they'd be better off bowing out. In this experiment, a measured attitude beats a gung-ho one.

The test asked the rat to classify a burst of noise as 'short' or 'long'. Noises that were very short or very long were easy to classify, but those of intermediate length were more challenging. After hearing the noise, the rat was offered two holes through which it could stick its nose - one for accepting the test and one for declining it. If it was up for it, it was then given two levers, one for a short noise, and one for a long one.

After some initial training, the results were clear. The rats were much more likely to opt out of the test if the noise they heard was challenging.

A bird can use rocks to raise the level of water so it can drink:

Here's Part I, Part II, and Part III of the series.