Is handedness present in animals?

I’m just wondering if anyone knows whether animals have a preference for using one side of their bodies over the other, just as people do. I notice that one of my cats almost always swats at me with her left paw. She also has a tendency to chew mostly on the left side; last time she was at the vet he remarked how clean the teeth on the right side of her mouth were compared to those on the left. Anyway, I figure she must be a southpaw. If anyone has ever read anything about this, I’d love to know more, and also if handedness IS present, whether it breaks down in the same proportions among animals as it does with people. For instance, is my left-pawed kitty in the minority just as left-handed people are?

Anyway, I figure she must be a southpaw.

No pun intended, right? Well you just kinda non-scientifically answerd your own question. I was think about cat’s when I saw that topic name but rather most other animals (that don’t use their paws like hands as much…dogs, some wild animals…) I was going to say that they probably do have a prefrence, but about as significant as the prefrence we have with one foot over the other. BTW we do also have a foot prefrence (if you snowboard you know this) they way to find out is to imagine sliding on wet ice, which foot is foward. Or, have someone push you lightly when you are standing up (a little bit of surprise helps) and look at which foot goes out to catch yourself.
(BTW just for a little bit of useless fact type stuff, if you are left foot foward, you are regular and if you are right foot foward it is called “goofy”)

Formerly known as Nec3f on the AOL SDMB

Maybe the dog owners should take notes on which way their pets circle when bedding down–but then someone would probably bring up drains and the Equator!
–Alan Q

Look at lobsters…most have a larger right claw and a smaller left claw. But some, the lefties, have a larger left and a smaller right.

Yes, handedness (biased asymmetry) is present in many animals, and even in plants. LOTS of things are naturally asymmetrical, and often will not have 50/50 variants. Flatfish (flukes, flounders, halibut) lie predominantly on their left sides, IIRC. Most snail species have right-handed spirals, except for one, called the “Left-handed Whelk”. Lobsters have already been mentioned, and there are many other crustaceans (esp. fiddler crabs) with similar claw asymmetries. There are literally hundreds of thousands of insect species where the mouthparts and/or genitalic structures are distinctly asymmetrical, and always the same way. At any rate, pay close enough attention and you can find handedness all over the place in nature.

Do octopi have dominant tentacles?

One of my dogs is left handed, er, pawed, and the other one is right.

As for octopi, stick your hand out to it, and see if it reaches for you with it’s left or right tentacles.


Saw a story either today or yesterday in El Pais about how some butterflies are either left- or right-winged (This is NOT a joke). Apparently, their wing dominance makes it easier for them to fly in the patterns necessary for mating.

By the way, Cecil answered the question of handedness in animals - specifically about cats.

horses exhibit “sidedness,” in other words, they tend to be more flexible on one side of their body than the other.

This can be corrected or exacerbated through training. Extreme example : horses that are trained for racing often are severely left-sided, because in the US horses race clockwise, and they’ve only ever run with their body curved to the left.

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