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Every human has a strong preference when choosing which hand to write with, and even crows have even been found to have a favoured side when using their beak as a tool.

Now new evidence suggests that ants tend to turn left when exploring new surroundings.

A study has found that the insects are significantly more likely to turn left than right when exploring new nests.

In the experiment, a directional choice for left or right was determined if an ant remained within a body's width of the wall closest to the entrance, for half the wall's length; otherwise its choice was recorded as 'other'. The route of a specific ant within the manmade maze is illustrated here

This behaviour was also recorded when Temnothorax albipennis, or rock ants, were put in mazes, although this preference was initially obscured by ants' typical wall-following behaviour.

Why ants may have this bias for the left remains unknown although biologist Edmund Hunt, who was involved in the University of Bristol study, told Phys.org: 'The ants may be using their left eye to detect predators and their right to navigate. Also, their world is maze-like and consistently turning one way is a very good strategy to search and exit mazes.'

In the study, ant colonies were placed in a large square Petri dish, which acted as a 'nest', measuring 23cm by 23cm.

The colony's nest entrance was opposite that of an unknown nest.

The colony's nest entrance was opposite that of an unknown nest. All starting nests were of the same dimensions as the unknown nest in the experiment. Exploration was encouraged by removing a temporary cardboard cover from the starting nest to increase its light level and make it less attractive to the ants

The unknown nest was darker than the starting nest - making it more attractive to the ants as they lives in dark rock crevices in the wild.

Scientists stimulated exploration of the unknown nest in the experiment by destroying the starting nest.

After ants had explored and exited the new nest, they were removed to a separate holding dish until the end of the experiment to prevent them from participating in a second trial.

After each ant exploration, a new wall was put in place to prevent the accumulation of ant pheromones - chemical messengers - that could affect an ant's choice of direction.  

LEFT OR RIGHT-BEAKED? HOW CROWS HAVE PREFERENCES TOO 

Researchers studying New Caledonia crows have discovered that crows display a preference for holding a stick tool on a certain side of their beaks - and this could be to make the most of their wide field of vision.

Caw-blimey! Experts believe a crow's preference helps them maximise their field of vision

Researchers believe the birds may be trying to keep the tip of the stick in view of the eye on the opposite side of their heads, so they can see clearly in order to use tools in the most dexterous way.

Lead scientist Dr Alejandro Kacelnik, from Oxford University, said: 'If you were holding a brush in your mouth and one of your eyes was better than the other at brush length, you would hold the brush so that its tip fell in view of the better eye. 

This is what the crows do.'

New Caledonian crows have surprised experts with their ability to use sticks to extract larvae from burrows and, in captivity, retrieve food placed out of reach. 

Scientists at the Language, Culture and Cognition lab at the University of Auckland have been studying the intelligence of tool-making New Caledonian crows for over 10 years.

They have shown that crows can use tools to solve eight problems in a row. 

A directional choice for left or right was determined if an ant remained within a body's width of the wall closest to the entrance, for half the wall's length; otherwise its choice was recorded as 'other'. 

In the experiment the ants overwhelmingly chose to turn left, as opposed to right, when exploring the new nest.

Regional brain specialisation of tasks has been observed a in many animal species and is beneficial since it allows animals to carry out two tasks simultaneously without sacrificing efficiency.

For instance, a right eye/left brain hemisphere bias for identifying prey, and a left eye/right brain hemisphere bias for predator detection and escape, are reported in fish and lizards, among other vertebrates.