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  • It's AumSum Time.

  • Can you guess the title of my next video?

  • Hurry up.

  • Write your guess in the comments section below.

  • Are dolphins smart?

  • Not smarter than me.

  • I'm the smartest of them all.

  • You wish.

  • Dolphins belong to the family of cetaceans which includes aquatic animals like whales and porpoises.

  • Cetaceans have gradually evolved over millions of years to become the present-day dolphins which have large, complex brains.

  • Now, coming back to the question, are dolphins smart?

  • The answer is yes.

  • The large complex brains of the dolphins help them perform various functions which are usually not seen in other animals.

  • One of these functions is human like socializing.

  • Which can be seen when bottlenose dolphins form a group to hunt.

  • By beating its tail.

  • A bottlenose dolphin from the group stirs up the seabed and starts to make a circular ring of mud around a shoal of fish.

  • Then, by making the ring smaller and smaller, it traps the shoal of fish.

  • Now, another bottlenose dolphin in the group signals the remaining dolphins to line up around the circle.

  • So, when the confused and trapped fishes try to escape by jumping out of the mud ring.

  • They end up in the dolphins' mouths.

  • In addition to this, although dolphins have eyes to see.

  • They even have the ability to echolocate which can help them navigate better especially in murky water.

  • To echolocate, dolphins produce high frequency sound waves which travel through water.

  • Get reflected from obstacles as echoes.

  • When these echoes return to the dolphins, they are able to identify the location, shape, etc. of the obstacles.

  • Hence, using this method, they easily avoid the obstacles and navigate in murky water.

  • Moreover, it is also observed that using low frequency sounds, dolphins communicate with each other.

  • They even have signature whistles, like names, which they use to call each other.

  • According to a study, it is also believed that dolphins can recognize themselves in the mirror.

  • This quality of physical self-awareness is not usually present in other animals.

  • Topic: Vaccines.

  • How do vaccines work?

  • By giving extreme pain.

  • Not at all.

  • Vaccines train our body to fight against the dangerous disease causing pathogens.

  • Oh really.

  • Do they have a training academy?

  • You are just unbelievable.

  • Vaccines often contain weakened or dead pathogens.

  • When they are injected into our body, they just trigger the immune response but do not cause fully-fledged diseases.

  • Our immune cells recognize these pathogens as foreign invaders and thus, produce antibodies.

  • These antibodies kill the pathogens.

  • Also, the immune cells record the information about the pathogens and the way they were killed.

  • Hence, in case in the future, a similar strong pathogen enters our body.

  • Our immune cells remember and easily identify that pathogen.

  • They produce the required antibodies to fight it back.

  • Thus, we remain healthy.

  • Why pop rocks pop?

  • Because they have springs in their legs.

  • No.

  • Pop rocks are tiny candy crystals.

  • Candies are usually made using sugar, water, corn syrup, various flavorings, etc.

  • Initially, all these ingredients are mixed together.

  • The resulting solution is heated until most of the water boils off and we are left with a thick sticky syrup.

  • Usually, this syrup is poured in moulds and allowed to cool and harden to make candies.

  • However, to make pop rocks, highly pressurized carbon dioxide gas is added to the syrup.

  • Then, it is cooled to subsequently form a hard candy.

  • This results in the formation of small bubbles of pressurized carbon dioxide trapped inside the candy.

  • Now, when we put this candy in our mouth, our saliva dissolves the candy.

  • As a result, the highly pressurized carbon dioxide escapes from the bubbles with a pop.

  • Why are sunsets red?

  • Because sunsets are romantic.

  • No.

  • It is basically because of scattering of light in the atmosphere.

  • Our atmosphere is primarily composed of tiny nitrogen and oxygen particles.

  • Now usually, when sunlight comprising of seven colors passes through the atmosphere.

  • It hits the nitrogen and oxygen particles.

  • These particles scatter blue and violet light more as compared to red, orange and other colored lights.

  • Hence, mostly bluish light enters our eyes, thus making the sky to usually appear blue.

  • However, during sunset, the sunlight must pass through a greater distance in the earth's atmosphere.

  • Causing it to pass through more particles.

  • As a result, most of the blue and violet light get scattered before they reach our eyes.

  • Due to this, the less scattered light like red or orange reaches our eyes, making the sunset appear red.

  • Topic: Heat transfer.

  • Why do we use a black umbrella in summer?

  • Hey.

  • Looks like you are heading out today.

  • But it is so hot outside.

  • Why don't you take a dark colored umbrella, preferably black?

  • See, I warned you.

  • At least now use the black umbrella.

  • Now, do you notice the heat?

  • No, right?

  • Do you know why?

  • This is because in summer season, the temperatures are quite high.

  • Now, as compared to other colors, a black colored umbrella, being dark, absorbs most of the light.

  • Ultraviolet radiations coming from the sun and gets heated.

  • It then radiates the heat back into the air.

  • Thus, making a black umbrella, a good choice to use in summers.

It's AumSum Time.

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    AumSum に公開 2021 年 01 月 14 日
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