Fish aren't known for being the brightest creatures under the sea. But new research suggests they're smart enough to at least follow the plot of Dr. Suess' "One Fish, Two Fish." It turns out fish can count.
For years, scientists didn't believe that fish were cognitively capable of counting, and that the human ability to count couldn't be traced all the way back to fish. But fish actually measure their 1-2-3's in a similar way people do.
Counting may not sound so advanced, but it really comes in handy for animals.
At a glance, animals can tell around how much food there is to go around, which group of fellow creatures is bigger and how many options you have for mating.
The scientists tested the fish's counting ability by seeing if they could reliably choose the bigger pile of snacks.
Over and over, the fish made the right choice.
Now we're starting to see why this skill is so important — for snacks!
Researchers had tested the counting ability of fish before, but in more of a life-or-death situation. (Wait, snacks aren't a life-or-death situation?) They tested how well fish could identify the larger group of fish, which is important for safety — fish are safer when they're part of a big group of their friends.
But this newer test showed that fish could estimate the larger number even when only mild hunger was on the line.
Researchers were also surprised to find that fish and humans change counting methods at around the same number.
Both of us tend to be pretty particular when we're counting small numbers, but at a certain point, we tend to just approximate.
Kind of like counting three cars driving down the road as opposed to enumerating every vehicle on the highway.
Both fish and humans switch to the more approximate version of counting at around the number four. Which sounds kind of lazy, but whatever!
All of this fishy research has actually left scientists with kind of an existential dilemma. Could humans and fish may be more closely related in the evolutionary family tree than previously thought?
Researchers will need to run a few more studies — three, four, OK, we're tired of counting — to find out for sure.