Recent research reported by Dr Calum Brown of Macquarie University in Australia showed that some species of parrot such as the sulphur-crested cockatoo were entirely left-handed while others, including the king parrot, were mainly right-handed. The majority of parrots, including the budgie, galah and rainbow lorikeet – are ambidextrous.
”This is probably the first time we see some kind of mechanism trying to explain how handedness came about in the first place,” Dr Brown said. ”It’s clearly linked to brain lateralisation. So the brain lateralisation determines eye lateralisation, which determines hand preferences.”
There have been lots of reports over the years about various animals showing hand preference and here is a brief summary:
- Psychologists from Queen’s University Belfast, who as part of their research played with 42 pet cats for weeks on end. They found that females are ‘right-handed’ while toms favour the left.
- Dogs are the same – until they are spayed or neutered, when the difference disappears, suggesting hormones play a role in left or right-handedness.
- Dogs wag their tails to the right when relaxed and to the left when agitated.
- Toads are mostly right-handed and pounce more quickly on morsels of food that enter their line of vision from their right.
- Fish will have a preference to left or right when they dodge a predator – this is likely to allow them to use a specific eye and side of the brain to deal with the threat. To test it out, place an unfamiliar object in the centre of your fish tank and watch which way your pet swims round it.
- Humpback whales prefer to use the right side of their jaws to scape up sand eels from the ocean floor.
- There has been a long-running Internet Meme that all polar bears are left-handed but we cannot find any scientific evidence to support it. In fact, one study of injury patterns in polar bear forelimbs found injuries to the right forelimb to be more frequent than those to the left, suggesting, perhaps, right-handedness.
If you come across any other reports on animals that are left-sided or disagree with any of those above, please
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