Tag: til

Human Echolocation – Seeing With Your Ears

By Anupum Pant

Bats can see, but Daniel Kish can’t. Due to Retinal Cancer (Retinoblastoma), Daniel has been completely blind since the age of 13 months. To save his life, both his eyes had to be removed at a young age. But, even with no eyes, he can see. He sees with his ears. People call him the real-life batman.

What? When Daniel was young, he started making a clicking sound with his tongue to understand his environment. Little did he know, at a young age, he had mastered Echolocation – A technique used by dolphins, and bats to navigate when there is no light. At the age of 11, only when a friend told him about Echolocation, did he realize what he was really doing.

How? By listening to the reflected clicking sound, Daniel is able to map the shape, dimension, depth and density of objects in his brain. Like we use light to see, he uses sound to create a 3D map in his brain. He has trained his visual cortex to process non-visual information. With this ability he is able to ride a bicycle around, effortlessly. Think about riding with your eyes closed. He does it everyday.

According to him, what he does isn’t rocket science. He thinks every one, if trained well, can do it. With a concern for blind people around the world who aren’t encouraged to use echolocation to move around, he started an organization where he teaches people how to do it. You can watch his TED talk here. [video]

Side note: In a Tamil movie, Taandavam, he was the one who taught Shiva to move around using echolocation.

If you think Daniel’s ability doesn’t talk enough about the amazing human brain. This video of David Eagleman talking about how our brain perceives the world, will probably make you appreciate it [the brain] more. Watch it till the end where he talks about these plug-in-brain devices.
In short, brain can learn to interpret various kinds of signals to produce an image.

[read more]

Elephant Bird – The Heaviest Bird Ever

By Anupum Pant

Scientific Name: Aepyornis maximus

No, it isn’t about a bird with a trunk or tusks. Weighing almost half a ton, the aptly named, elephant bird of Madagascar, was the heaviest bird to have ever existed on earth.  It looked like an Ostrich on steroids and of course it was a flightless bird. The number 3 bird in this picture is an illustration of the Elephant bird (around 10 feet in height) [image]

Note: Although we say that it was the heaviest bird to have ever existed, we can only say that because we haven’t been able to find any traces of a larger bird yet.

Interestingly, it wasn’t something that belonged to the Dinosaur era. It went extinct recently, around the 17th or 18th century, probably due to humans hunting it for food. Since cameras did not exist at that time, only written accounts of its sighting have been found.

As logic dictates, a huge bird would lay huge eggs. So, with a volume of about 180 to 250 times that of a chicken egg, measuring about 1 feet in height, its eggs were the largest laid eggs ever; larger than human heads. The shells could hold around 11 liters of liquid. Its eggs were said to have fed whole families. Some of them have been preserved – Some are being auctioned and some are available in museums. National Geographic Society in Washington holds a specimen that has the skeleton of an unborn Elephant bird.

 

Klein Bottle – A Bottle That Contains Itself

By Anupum Pant

To appreciate the beauty of mathematics and nature there is no escaping without learning about a Klein Bottle. A three-dimensional representation of a Klein bottle looks like this – [image]

There are number of phrases you can use to describe (not exhaustively) it. A few of them are as follows:

  • An object with no boundaries.
  • An object with no inside or outside.
  • One sided surface.
  • Non-orientable surface

Wikipedia describes it as:

The Klein bottle is a non-orientable surface; informally, it is a surface in which notions of left and right cannot be consistently defined.

Simplifying things: A Möbius strip is a simpler example of a non-orientable object. That means it has no inside or outside. Add another aspect – having no boundaries – to it, it gets more complex and you end up with a Klein bottle.
If you haven’t heard of Möbius strips, to understand such surfaces, you can make one for yourself now.

  1. Tear off a strip of paper.
  2. Hold it horizontally, straight with both of the short edges in your hands.
  3. Now, twist one of the edges by 180 degrees and join the two short edges. You’ll have something like this in your hands – [image]

Test the surface and edges: On this object you just created, move your finger along the surface. You’ll find that your finger comes  back to the same place eventually. There is no inside or outside for this object, there is just one surface.
The same thing happens with its edge (try moving your finger along the edge). Here is a Music box playing a Harry Potter theme continuous – forward, inverted, forward and so on – manner; Relevant video: [video]

Now spin it (the Möbius Strip) fast. You can NOT practically do it. I mean, spinning it like you spin a circle and get a sphere. There! You have a Klein bottle. It is better than a Möbius strip in a way that it (Klein Bottle) has no boundaries.

Klein bottles cannot actually exist in our three-dimensional worlds, the ones that look like them (Klein Bottles) are just 3D representations of a 4D object. Like a two-dimensional drawing of a 3D cube. These models are available for you to buy. Interestingly, in spite of having no inside or outside, they can be filled with a liquid. But, given the opposing force of air, they are pretty tough to fill. It is important to note that the 3D representation of a 4D Klein bottle has an intersection of material, this doesn’t happen in 4D. It is like the intersecting edges of a 3D cube in the 2D representation.

You’re thinking 3D? At MIT (and other places) 4D printing is already happening.

If you are having a tough time imagining this 4D object, the following 4D animation might help (or leave you perplexed) – [video]
[Extra reading for math geeks] as if they already didn’t know about Klein bottles.

Axolotl – A Walking Fish That can Regenerate Limbs

By Anupum Pant

If you are looking at an Axolotl for the first time, it will confuse you. With an oddly shaped body that resembles both a catfish and a salamander, you’ll wonder if it lives in water or on land. [Image]

What is it?

A fish? Axolotl, commonly known as the Mexican Walking Fish, isn’t actually a fish. It is an amphibian, which means it has both lungs and gills. They almost never come out of water, hold their breath and take in oxygen using their gills (those three pairs of parts coming out at the back of its head are the gills). They can hold their breath for a year, beat that Mr. David Blaine.

Or Salamanders? They are closely related to salamanders and interestingly the adult Axolotls look like baby Salamanders. They have long abandoned the usual amphibian-transformation from a larva stage to an adult. Unlike Salamanders, they don’t transform into adults that can live outside water. They stay in water and walk around on the water-bed.

However, strange species of Axolotl was once delivered to a zoologist Auguste Duméril, which had somehow transformed like salamanders and would happily come out of water. But this transformation (metamorphosis) shortened their life span. Later it was found that this process can be artificially triggered by injecting iodine. (Do NOT try this at home)

As pets: Today, these animals are fairly common and are used as exotic pets all around the world. Especially in Japan, people love to have them in their aquariums.

Side note: Like several other Pokémon based on real animals, Whooper and Mudkip were actually based on Axolotls.

Regenerative Powers

Besides having the ability to walk underwater and its unusual appearance, there is something that is much more interesting about them. Unlike, almost any other vertebrate, they have the power to regenerate various cells. Not just cells, Axolotls can regenerate complete body parts – limbs, gills, eyes, kidneys, even large portions of its liver and its heart muscle. Even portions of its spine and brain can be regenerated. They are able to grow back a severed limb in span of few months. This is the reason scientists love these creatures and conduct a number of studies on them every year.

Tardigrades – Toughest Creatures on Earth

By Anupum Pant

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So, if you think elephants or cockroaches are tough, that could be because you probably haven’t heard about these amazing creatures called Tardigrades (picture).

What are Tardigrades?

Tardigrades, also known as moss piglets or waterbears, are oddly cute little animals that live in water and feed on moss. Their size ranges from 0.1 mm to 1.5 mm and they have eight legs (they walk like bears). The most extreme thing about these extremophiles is that they can survive almost anything (actually, they kind of die for a while with an option to come back to life later). Here is a list of things Tardigrades can survive. They can:

  • Survive without water and food for 10 years.
  • Waddle away in the vacuüm of space (for 10 days & get exposed UV radiation), come back and walk around as if nothing happened.
  • Survive 1000 times more radiation that would kill an elephant.
  • Live through extremely low temperatures (almost absolute zero) or high temperatures (~150 degree Centigrade)
  • Repair their own DNA after getting exposed to lethal amounts of radiation.
  • Survive pressures of about 300 Jumbo jets stacked on a person. (6 times more than the deepest ocean trenches)

Scientists love them

People at NASA and the European Space Agency love doing tests on them because they think, Tardigrades can help them understand the origin of life on earth (probably by supporting Panspermia). Also, scientists want to find out more about their extreme capabilities. If you ask them, if these things are aliens, they’ll tell you – “Probably not”

[Learn more about Tardigrades]