In tests, aboriginal children listened to taps from a stick and then put out markers to match the number of taps they heard. For example , if they heard four taps, the scientist wanted to see if they put four markers. They had to connect numbers with sounds and with actions, without seeing written numbers. In the tests, the children put out the correct number of markers. They were able to count even though they didn’t have words for numbers. Experts believe this shows that humans have a universal ability to count.