Why do cats always land on their feet? "The secret is in their spine”, Flemish biologist says

"The upper part of a cat’s spine is exceptionally flexible, while the lower part is twice as heavy”. Meanwhile, the research also raises a number of questions. “When a cat falls it almost always turns towards the right, but why this is the case is still unclear”.

Dirk Draulans when on to tell VRT Radio 1’s ‘Nieuwe feiten’ (new facts) that “Since the 18th century physicists have been asking themselves this question. Even the 2 founding fathers of modern physics Isaac Newton and James Maxwell were unable to find a conclusive explanation. The laws of classic natural science stay that a body can not just start turning without external force being applied”.

However, experiments carried out by French physiologist Étienne-Jules Marey in 1894 proved that cats can do just that.

Early photography was used to demonstrate that cats turn round during their fall without any push or momentum. Something that had been the source of speculation at the time, as there was no way to actually test this within the confines of an experiment.

“It was initially believed that they do this by tucking in their front legs and extending their hind legs, which might have an effect. It’s similar – though the analogy isn’t perfect – to figure skaters tucking their arms in to spin faster”, Dirk Draulans told VRT News.

James Maxwell also assumed the curvature of the cat’s body played a role: the front part reacted differently from the rear.

“A third idea was that the tail acts like a propeller, thereby causing a counter-rotational movement. This hypothesis has long been accepted,” Dirk Draulans explains.

According to new research by biomechanics experts at Yamaguchi University in Japan, the answer lies in the cat’s spine. “This research has finally solved a great mystery in the animal kingdom”, Dirk Draulans says.

"The researchers carried out a classic experiment with cats, dropping them from a height of 1 metre onto a soft cushion (120 frames per second). They also examined the spines of five dead cats by rotating them until they snapped.

“This showed that the front part of the spine, at chest level, is exceptionally flexible and can rotate by up to approximately 47° without any resistance. Meanwhile, the rear part of the spine is much stiffer. This allows the cat to rotate its front body first, whilst the heavier rear body briefly acts as an anchor.”

“Using high-speed cameras, the scientists observed that this difference amounts to between just 70 and 90 milliseconds. However, yet it is sufficient to ensure a successful landing. Combined with the retraction of the front legs and the extension of the hind legs, this creates a rotational movement without breaking the laws of physics.”

According to new research by biomechanics experts at Yamaguchi University in Japan, the answer lies in the cat’s spine. “This research has finally solved a great mystery in the animal kingdom”, Dirk Dra ulans says.

"The researchers carried out a classic experiment with cats, dropping them from a height of 1 metre onto a soft cushion (120 frames per second). They also examined the spines of five dead cats by rotating them until they snapped.

“This showed that the front part of the spine, at chest level, is exceptionally flexible and can rotate by up to approximately 47° without any resistance. Meanwhile, the rear part of the spine is much stiffer. This allows the cat to rotate its front body first, whilst the heavier rear body briefly acts as an anchor.”

“Using high-speed cameras, the scientists observed that this difference amounts to between just 70 and 90 milliseconds. However, yet it is sufficient to ensure a successful landing. Combined with the retraction of the front legs and the extension of the hind legs, this creates a rotational movement without breaking the laws of physics.”