As humans, we often hold a dominant hand.
The majority of people (70-95%) are right handed.
The other 5-30% are left handed.
In addition, approximately one percent of the population are ambidextrous, meaning that they can use both hands equally well.
Like humans, parrots have two hands (or if you want to get technical, two feet), but do they display handedness like we do?
If they do show handedness, are all parrots the same, or are some left handed and some right handed?
As I was writing a journal entry with my right hand the other day, I found myself pondering this question.
So I set in search of an answer.
Here’s what I found:
Yes! Parrots do have handedness. Like humans, they show preference towards using one hand (or foot) more than the other. And while not all parrots are the same, the majority of parrots that have been studied tend to show a preference to their left side (which is opposite that of humans).
But what is the ratio of left to right footed parrots?
How is handedness tested in parrots?
Why are parrots handed?
And how is handedness in parrots teaching us more about our own handedness?
Today we will answer all of these questions and more so let’s not waste another minute!
Do Parrots have a Dominant Foot?
As we have already learned above, the answer to this question is yes.
But let’s elaborate.
According to a study conducted on over 320 different parrots, approximately 47% of parrots gravitate to using their left claw, 33% to using their right, and the remaining parrots were ambidextrous.
That means that like humans, parrots do tend to show handedness, but unlike humans parrots tend to be more left-handed than right-handed.
Parrots also differ from humans in another way: they aren’t born right or left handed.
Rather, it appears that parrots experiment with both sides before they decide on a dominant foot.
Some species of parrot vary in handedness, while other species all seem to show the same handedness.
For example, as babies, Sulphur-Crested Cockatoos all experimented with both hands.
As adults, however, they were all found to be left-handed.
In other words, there were no right-handed sulphur-crested cockatoos.
Furthermore, the research found that handedness in parrots was also related to their eyes.
Unlike humans who have eyes in the front of their head, parrots eyes are located at the side.
In order to look at something then, a parrot has to tilt its head.
When studying handedness, researchers consistently found that a parrots dominant foot was the same as their dominant eye.
In other words, a parrot that preferred to use the left foot also preferred to use the left eye.
Why are parrots handed?
Most things in life have an evolutionary purpose.
But what is the purpose of handedness in parrots?
In humans, handedness is thought to be linked to the idea of lateralisation, or the use of one hemisphere of the brain over the other.
But what seems to be important is not what side the brain is lateralized on, but exactly how strong the lateralization is.
To elaborate, research has shown that people who are strongly lateralized are better at solving complicated problem-solving situations.
In other words, people that are strongly left or right handed are better problem solvers.
But what does this have to do with parrots?
This same lateralization that is present in humans is also present in parrots.
And strong lateralization may be associated with skills that are necessary to a parrots survival – like foraging.
Parrots that have strong lateralization may be better at searching for and finding food which, in the wild, is essential for their survival.
How do we test for handedness in Parrots?
To keep things simple, handedness in parrots can be studied by monitoring their behavior.
In one study by Herbert Friedman and Malcom Davis, 20 birds were caged and monitored in the morning.
To determine their handedness, an apple was placed in the center of the floor of their cage.
The center was chosen as the best location because it meant that the apple was equally approachable from both the left and right side, leaving no room for bias due to locationing.
A few days later, the same birds were observed with a carrot instead of an apple.
The same study was then conducted a year later to confirm the results.
After monitoring the parrots in depth, researchers found that they had a tendency to use one foot to grab and eat the food.
In other words, the food was not shifted from foot to foot, and the parrots tended to show a preference of handedness.
The majority of the birds (72%) showed preference of using the left foot.
Is handedness in parrots a sign of intelligence?
It certainly does seem that way!
According to research done at Macquarie University in Australia, birds that were ambidextrous were not as intelligent as birds that showed some degree of handedness.
Researchers Maria Magat and Culum Brown from the University studied 8 different species of Australian parrot, some of which were left handed, some of which were right handed, and some of which were ambidextrous.
Handedness was determined either by which foot was used primarily to pick up food, or in the cases of birds that didn’t use their feet, which eye was used to search for the food.
Once handedness was determined, the birds were put through a series of problem solving tasks such as foraging for seeds.
Results showed that parrots who showed strong handedness, or preference to use one side or the other, were much faster at solving the tasks than birds that were ambidextrous.
With that being said, there didn’t seem to be much of a difference between left and right handed birds.
In other words, it didn’t seem to matter which hand a bird used, it simply mattered that they showed a strong preference to one hand or another.
It seems then that lateralization (or being strongly handed) helps to improve aspects of problem solving for birds.
Can Lateralization help parrots guide the flock?
We’ve already established that handedness can be beneficial when it comes to foraging for food, but can it help parrots to guide the flock too?
The answer may be found in studies conducted by Mandyam Srinivasan from the University of Queensland.
The neuroscientist wanted to study how birds learn to travel and land in trees without colliding into other birds or crashing into branches.
To find the answer, he studied a series of budgies.
In the study budgies were sent to fly through a tunnel with cloth gaps on either side of them.
The gaps between panels varied from flight to flight, with over 100 flights in total for each bird.
When one gap was wider than the other, birds tended to fly through the wider gap, as would be expected.
But when gaps were even on both sides, birds tended to show a preference towards the right or left gap.
The number of birds was split evenly from right to left.
Furthermore, in subsequent studies, there seemed to be an equal number of birds that preferred the left to the right birch to land on.
But how is this helpful?
According to Srinivasan, if a flock was evenly split between left and right handed birds, this would make avoiding collisions and landing on branches more efficient.
Imagine if all birds were left handed and tried to land on the same perch?
Or if all birds were right handed and trying to fly in the same direction?
This would be chaotic and would surely lead to collisions.
But when left and right preferences are divided equally among the species, landing and flying become more efficient and safer.
In conclusion, research has found that parrots, like humans, tend to show handedness, or a preference towards using their right or left hand.
The majority of parrots tend to be left handed though some also show right hand preference, and others show a tendency to use both.
Though being left handed doesn’t show any benefits over being right handed, being strongly lateralized does seem to have a correlation with intelligence, which could be beneficial to a parrots survival in the wild.