Fascinating World

A small attempt to gather unusual and amazing facts about elements of Nature.


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Tree-climbing Robber Crab

[Please Note: I would like to state that I have not experienced / seen any of the facts mentioned here. I am curious about the various unusual phenomenon occurring in nature. I have only researched and compiled these facts together. The images presented in this blog are not photographed by me. Thank you.]

Robber crab is another name for the Coconut crab.  They are also known as Palm thief. The scientific name is Birgus latro and the coconut crab is the only species of the genus Birgus. This species is a terrestrial hermit crab. Continue reading

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Tiny, Colourful — and Lethal.

[Please Note: I would like to state that I have not experienced / seen any of the facts mentioned here. I am curious about the various unusual phenomenon occurring in nature. I have only researched and compiled these facts together. The images presented in this blog are not photographed by me. Thank you.]

They look so bright and colourful, but they are dangerous — these are Poison Dart Frogs.

 

Image result for purple poison dart frog

Image Source: Here

The scientific name of these amphibians is Dendrobatidae. Generally these are small in size, from 1.5 cm to maximum 6 cm. Their life span is 3 to 15 years. The habitat of the poison dart frogs is the tropical rain forests of central and south America. These frogs live in trees and leaves, under logs and rocks, but always near water bodies (like other amphibians.)

Image result for poison dart frog

Image Source: Here

The bright colouring of these creatures ranges from gold, yellow, red, green, blue, copper, black etc. Their brilliant neon colours are a warning for the predators. (This is called as aposematic colouration). The frogs with cryptic colouration possess minimal to no toxicity.

Image result for poison dart frog

Image Source: Here

These creatures are considered as some of the most toxic animals on the earth. The golden poison dart frog contains enough poison to kill ten men or around ten thousand mice. For centuries, the original inhabitants of Colombia used the potent poison of these amphibians to tip their hunting arrows or darts; that’s how the Dendrobatids acquired their commonly used name ‘Poison Dart Frogs’.

 

Image result for poison dart frog

Image Source: Here

It is a hypothesis of the scientists that these frogs derive this poison from their preys like ants, termites, millipedes, beetles etc. An experiment was carried out wherein these frogs were raised in captivity and they were deprived of the preys of their natural habitat. It was observed that these frogs did not develop any poison.

The poison is in alkaloid form and is stored in glands beneath their skin. There are two-three different types of alkaloids, namely Batrachotoxin, Epibatidine and Phantasmidine. These poisons are found on their skin, so the frogs are toxic to touch. (Many species are toxic but not deadly). These alkaloids (poisons) can cause swelling, nausea and muscular paralysis. Even little amount can cause brain and muscle damage, leading to respiratory paralysis, seizures and death.

The female frogs lay their eggs in trees and leaves and when the eggs are hatched, the mother gives piggy-back rides to the tadpoles and take them near water. The females lay more (unfertilized) eggs to feed the tadpoles, their poison is passed through these eggs to the tadpoles. Thus even the young ones of the poison dart frogs have protection against the predators.

Scientists are presently working on the poisonous alkaloids secreted by these frogs. Although these are lethal, they also can numb pain; so these are being used for developing effective pain-killers.

These frogs face danger of extinction because they are fast loosing their habitat to human encroachment and also, these neon coloured animals are captured for trade.

 


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Cat’s Eyes

We all admire the bright, colourful and shining eyes of a cat. But apart from the colourful prettiness, it also has some unique features.

Fellow blogger (Mr. Amit Misra, pradyot.net)  gave a constructive suggestion that instead of always writing about amazing creatures, sometimes strange facts about our everyday creatures also could be written. In addition, today is 181st birthday of French ophthalmologist Ferdinand Monoyer (who  invented the eye testing visual acuity chart). So this post is about the special characteristics of the eyes of our domestic cat.

Image result for eyes of cat

Source: Here

It is assumed that cats can see in total darkness, but this is not true. However, cats can see clearly in only one sixth amount of light that we humans require to see.                          All eyes have a lens through which the light passes and the amount of the light passing through the lens is controlled by an aperture or pupil. This light then falls on the retina to form an image. The retina is rich with receptor cells — rods and cones. The rods detect light and the cones detect colour.

In the cats, this rods to cone ratio is higher than that in the humans. So, they can detect much more light and have a better vision in dim light. Higher count of rod cells also allows the cats to detect even slightest movement.

The shape of the cat’s pupil is like a slit or elliptical shaped. The opening and closing movements of such pupil are faster than the round pupil of human eye. This helps the cat to quickly adjust to the changes in the surrounding light. (Therefore the cats do not get blinded by sudden brightness like we do).

Image result for eyes of cat

Source: Here 

When the light is in abundance, the slit-like pupil closes to reduce the amount of light entering the eye and thus protects the sensitive retina.

The cats are considered as colourblind; however, they do see the colours but in much less intense hues. The receptors cone cells which are responsible for colour detection are  less in number and these cells are not concentrated. So, for the cats some colours are muted than they are to us. They can differentiate blue-violets better than the red side of the colour spectrum.

The cats have a layer of reflective mirror-like cells at the back of the retina. These cells are called as Tapetum lucidum. These cells collect and reflect all the available light within the eyes and so the cats are able to see even when there is hardly any light. These same reflective cells give a jewel like shine to the cat’s eyes in the darkness of the night.

Image result for tapetum lucidum

Source: Here

Most nocturnal carnivores and deep sea animals have this layer of cells. It improves the ability to see in the dark but reduces visual acuity.


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Clever Crow

Anyone would naturally say, what is so special about a crow, they are so common. And then, everyone has surely heard the story of The Clever Crow.

But this is not any story. These are facts, which have been proved scientifically.

The New Caledonian crow is capable of manufacturing  tools from naturally available materials and use these tools for retrieving food from nooks and corners. Continue reading


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When she becomes a mother…..

The appearance of an alligator is frightening, to say the least. And if it opens its jaws to reveal all those sharp teeth, then it is danger personified! An alligator has 70 or more sharp teeth. Imagine getting caught in those teeth!

However, when this same alligator has to look after her eggs or hatch-lings, these teeth handle those eggs with utmost care and tender touch. Unbelievable, isn’t it? Continue reading


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The Elephant: Some lesser known facts

Elephant, the biggest land animal, is fairly known to all. However, there are a few things which are not commonly known.

Did you know that the blunt looking trunk of the elephant is very sensitive? The trunk alone comprises of more than forty thousand muscles. The elephant can pick up even a thread from a smooth floor with the tip of its trunk. While crossing deep rivers the elephant uses the trunk like a snorkel. Continue reading