It’s not just dogs and cats that dream, of course. Any animal that engages in REM likely does too, which rules out most reptiles and fish. The frequency and duration of REM cycles vary wildly between species, meaning that although creatures like giraffes and hedgehogs probably dream, they do so fairly differently.
A 2001 study suggests that lab rats dream of labyrinths. By tracking these critters both engaging in REM and, earlier, running through a maze, researchers were able to use neuronal activity to work out what specific part of the maze they were dreaming about.
Zebra finches seem to dream of singing practice. During the day, they learn the notes needed to woo a mate or tell another bird to get lost.
Careful neuronal mapping by researchers back in 2000 demonstrates that the same synapse active during singing are also active during REM. In fact, the mapping was so accurate that the team could reconstruct the song, with the correct notes and in the right order, from start to finish just using data from the REM stages.
Several gorillas that have supposedly learned sign language, including Koko and the late Michael, have communicated to their keepers upon waking that they have dreamed of events. Michael was said to have signed about his mother’s death by poachers after having a nightmare about it.
Although it appears likely then that animals dream, it’s entirely unknown if they can dream of more surreal moments, in the way a person can dream of flying through the skies. It’s a wonderful thought though, a dog or cat looking up at the clouds one day, and then dreaming of zipping through them at night.
A sleeping ball of spikes. fotografos/Shutterstock
[H/T: People Magazine]