You can find all episodes released weekly and freely available here:https://www.youtube.com/channel/UCD6fsKTuRiOfW1L2cbXM_HQ
I’ve recently been making a documentary miniseries and podcast called “The Cabinet of Curiosities,” looking at the wonderful stories behind items in my own natural history collections. In the course of researching these shows, I’ve come across many a wonderful fact, so I thought I’d share a few in the days and weeks to follow. I very much hope you enjoy:
Fact: Zebras are black with white stripes, just like zebra crossings…
Historically, it was believed that zebras were white with black stripes. One explanation of this lies in the fact that some zebras have plain white underbellies with the black stripes extending only down their sides. The natural assumption was that these black stripes had been ‘painted’ on the white canvas of the body below. Nowadays, we know that zebra embryos have black skin. If you shave a zebra you would find the same: the underlying skin is a darker shade. Hence zebras strictly speaking are black with white stripes.
A perfect example of camouflage for the modern pedestrian environment…
What are these stripes used for? Now that’s a more interesting question. The answer is probably a mix of a lot of different factors: they help cool the animal, deter horseflies, provide a sort of disruptive camouflage when running, and allow zebras to recognize others in their herd. The stripes are like fingerprints- each pattern is unique. Only fingerprints don’t often save your life.
The classical explanation of a zebra’s stripes is that they play with a predator’s eyesight. An optical illusion if you will, with the animals’ shapes blending into each other. Sadly, scientists nowadays aren’t so sure. Most predators have poor long-distance vision, so the effect would only work up-close (by which time it’s too late). More importantly, new research shows stripes have no effect or may be counter-productive in a zebra trying not to be singled out in a chase.
The theory of motion dazzle- where stripes break up the outline of an object and confuse attackers- was widely used in the 2nd World War. Battleships were painted with zebra stripes, and canons too, but the theory itself was never really tested. That’s one bloody embarrassing mistake to make.
Fact: In the 19th century, a French entomologist fired a cannonball at a tree full of cicadas to see if they would stop singing.
A perfectly innocent-looking cicada. Who on Earth would want to attack it with artillery?
The scientist in question was Jean Henri Fabre, who described his little experiment in his Souvenirs Entomologiques amongst other works. Here’s what he wrote:
On one occasion I borrowed the local artillery, that is to say the guns that are fired on feast days in the village. There were two of them, and they were crammed with powder as though for the most important rejoicings. They were placed at the foot of the plane trees in front of my door. We were careful to leave the windows open, to prevent the panes from breaking. The Cicadas in the branches overhead could not see what was happening… Bang! The gun went off with a noise like a thunderclap. Quite unconcerned, the Cicada continued to sing. Not one appeared in the least disturbed …
He was trying to see if they were deaf as he suspected, and his results seemed to back this up. In fact, male cicadas do ‘turn off’ their hearing whilst singing, however they are very much not deaf. Simply the sound of a canon does not have any significance to a cicada, and with such a brief timespan in which to find a mate, it takes quite a lot to make them shut up!