--- title: How scientists test animal minds: the mirror test, puzzle boxes and Clever Hans — a lesson of Mova's school · trees and pragmatics description: «How scientists test animal minds: the mirror test, puzzle boxes and Clever Hans», a lesson of the biology course of Mova's primary school, sentence by sentence with dependency trees and pragmatics. It begins: Put a sticker on your forehead, look in the mirror and you pull it off at once: you know t --- [Mova](https://md.mova.elamur.ai/free/en/) · [this page in HTML](https://mova.elamur.ai/free/en/corpora/school/biology/389-how-scientists-test-animal-minds-the-mirror-test-puzzle-boxes-and-clever-hans/) [home](https://md.mova.elamur.ai/free/en/) / [corpora](https://md.mova.elamur.ai/free/en/corpora/) / [school](https://md.mova.elamur.ai/free/en/corpora/school/) / [Biology](https://md.mova.elamur.ai/free/en/corpora/school/biology/) / How scientists test animal minds: the… # How scientists test animal minds: the mirror test, puzzle boxes and Clever Hans Lesson 389 of the biology course of Mova's primary school: 20 sentences, each with its syntax tree and pragmatics. The lessons are written for Mova, and their agreed trees are part of Mova corpus 0.4 (CC BY-SA 4.0). How Mova does on its tests: [the lesson at school](https://md.mova.elamur.ai/free/en/school-run/biology/389-how-scientists-test-animal-minds-the-mirror-test-puzzle-boxes-and-clever-hans/). - [0](https://md.mova.elamur.ai/free/en/corpora/school/biology/389-how-scientists-test-animal-minds-the-mirror-test-puzzle-boxes-and-clever-hans/0/) — Put a sticker on your forehead, look in the mirror and you pull it off at once: you know the face in the mirror is you. - [1](https://md.mova.elamur.ai/free/en/corpora/school/biology/389-how-scientists-test-animal-minds-the-mirror-test-puzzle-boxes-and-clever-hans/1/) — In the mirror test scientists put a mark on an animal where it can see it only in a mirror and watch whether it touches the mark on its own body. - [2](https://md.mova.elamur.ai/free/en/corpora/school/biology/389-how-scientists-test-animal-minds-the-mirror-test-puzzle-boxes-and-clever-hans/2/) — Over a hundred years ago a horse called Clever Hans seemed to do sums by tapping his hoof. - [3](https://md.mova.elamur.ai/free/en/corpora/school/biology/389-how-scientists-test-animal-minds-the-mirror-test-puzzle-boxes-and-clever-hans/3/) — A scientist showed that Hans was watching tiny, unknowing movements of the people around him: they relaxed when he reached the right number, and he stopped. - [4](https://md.mova.elamur.ai/free/en/corpora/school/biology/389-how-scientists-test-animal-minds-the-mirror-test-puzzle-boxes-and-clever-hans/4/) — Since then scientists make sure the person testing an animal does not know the answer, so nobody can give hints by accident. - [5](https://md.mova.elamur.ai/free/en/corpora/school/biology/389-how-scientists-test-animal-minds-the-mirror-test-puzzle-boxes-and-clever-hans/5/) — A fair test must also suit the animal. - [6](https://md.mova.elamur.ai/free/en/corpora/school/biology/389-how-scientists-test-animal-minds-the-mirror-test-puzzle-boxes-and-clever-hans/6/) — A dog lives by its nose, so a mirror means little to it, but it can tell its own smell from another dog's. - [7](https://md.mova.elamur.ai/free/en/corpora/school/biology/389-how-scientists-test-animal-minds-the-mirror-test-puzzle-boxes-and-clever-hans/7/) — Good scientists repeat tests with many animals in other labs, use rewards, let animals choose to take part and never hurt them. - [8](https://md.mova.elamur.ai/free/en/corpora/school/biology/389-how-scientists-test-animal-minds-the-mirror-test-puzzle-boxes-and-clever-hans/8/) — In the mirror test a mark is put where an animal can see it only in a mirror; touching the mark on its own body suggests it knows the reflection is itself. - [9](https://md.mova.elamur.ai/free/en/corpora/school/biology/389-how-scientists-test-animal-minds-the-mirror-test-puzzle-boxes-and-clever-hans/9/) — Great apes, dolphins, one elephant and some magpies are reported to pass the mirror test, while most monkeys, dogs and cats do not. - [10](https://md.mova.elamur.ai/free/en/corpora/school/biology/389-how-scientists-test-animal-minds-the-mirror-test-puzzle-boxes-and-clever-hans/10/) — Dogs know the world mostly by smell, and one scientist reported that dogs spend less time sniffing their own wee than another dog's. - [11](https://md.mova.elamur.ai/free/en/corpora/school/biology/389-how-scientists-test-animal-minds-the-mirror-test-puzzle-boxes-and-clever-hans/11/) — Over a hundred years ago a scientist put cats in puzzle boxes and timed them; they got faster with each try, learning by trial and error. - [12](https://md.mova.elamur.ai/free/en/corpora/school/biology/389-how-scientists-test-animal-minds-the-mirror-test-puzzle-boxes-and-clever-hans/12/) — Clever Hans tapped right answers by reading tiny movements of the people watching, so he was clever at reading people, not at maths. - [13](https://md.mova.elamur.ai/free/en/corpora/school/biology/389-how-scientists-test-animal-minds-the-mirror-test-puzzle-boxes-and-clever-hans/13/) — Today the person testing an animal often does not know the answer, so they cannot give hints by accident. - [14](https://md.mova.elamur.ai/free/en/corpora/school/biology/389-how-scientists-test-animal-minds-the-mirror-test-puzzle-boxes-and-clever-hans/14/) — In the water jar test, based on an old fable, rooks and crows dropped stones into a tube until the water rose with a floating treat; children usually pass it at about seven or eight. - [15](https://md.mova.elamur.ai/free/en/corpora/school/biology/389-how-scientists-test-animal-minds-the-mirror-test-puzzle-boxes-and-clever-hans/15/) — In a test reported in 2021, cuttlefish waited for their favourite shrimp instead of eating a less tasty crab at once, which needs self-control. - [16](https://md.mova.elamur.ai/free/en/corpora/school/biology/389-how-scientists-test-animal-minds-the-mirror-test-puzzle-boxes-and-clever-hans/16/) — Alex the grey parrot learned to name colours and shapes, say the number of objects up to about six and say «none» when two things had no difference. - [17](https://md.mova.elamur.ai/free/en/corpora/school/biology/389-how-scientists-test-animal-minds-the-mirror-test-puzzle-boxes-and-clever-hans/17/) — When Alex named a thing correctly he was often given that very thing as his reward; scientists argue how much he understood, but he showed parrots can do far more than copy sounds. - [18](https://md.mova.elamur.ai/free/en/corpora/school/biology/389-how-scientists-test-animal-minds-the-mirror-test-puzzle-boxes-and-clever-hans/18/) — One clever animal might be special, or a test might have a mistake, so tests are repeated with many animals and in other labs. - [19](https://md.mova.elamur.ai/free/en/corpora/school/biology/389-how-scientists-test-animal-minds-the-mirror-test-puzzle-boxes-and-clever-hans/19/) — Good animal tests use rewards, let animals choose to take part and never hurt them, and many countries have rules to protect animals in science. - ← previous: [Surprising brains: tool-using fish, counting bees, laughing rats and clever pigs](https://md.mova.elamur.ai/free/en/corpora/school/biology/388-surprising-brains-tool-using-fish-counting-bees-laughing-rats-and-clever-pigs/) - next →: [How animals sleep: half-asleep dolphins, standing horses, short-sleeping giraffes and birds that nap in the air](https://md.mova.elamur.ai/free/en/corpora/school/biology/390-how-animals-sleep-half-asleep-dolphins-standing-horses-short-sleeping-giraffes-and-birds-that-nap-in-the-air/) - ↑ back to [Biology](https://md.mova.elamur.ai/free/en/corpora/school/biology/)