-------------------------------------------
This Is Why Water Striders Make Terrible Lifeguards | Deep Look - Duration: 3:34.
To us, water striders are almost magical.
I mean, come on, they're literally walking on water.
But come down to their level and it's a bit more… sinister.
These delicate little bugs have figured out how to master the elements -
and to exploit those who can't.
So how do water striders float where others sink?
The answer is those crazy long legs.
Water is pretty sticky stuff.
It likes to hold onto itself.
It sticks together especially well right at the surface.
If you're small, it can actually hold you up, as long as you don't break through that
surface tension.
It seems like the water strider's legs would just sink right in.
But they don't.
They make dimples on the surface.
That's because their legs are covered in tiny hairs called micro-setae that repel water.
The strider's entire body is covered in them.
Those hairs trap a layer of air that keeps the water from sticking to its body.
The water strider simply can't get wet.
That's how they can sit on top of the water without breaking through.
Plus they're pretty light and they spread out their weight with their front and back
legs.
They use their middle pair of legs to maneuver, by pressing down and back against those dimples.
Just like rowing a boat.
They can even catch some air.
Most of their fellow insects aren't quite as graceful.
Like this caddisfly.
Struggle as it may, it's stuck.. half-drowned…
Exactly what the water strider has been waiting for.
It probes for a weak spot
And pierces through - spitting digestive enzymes in that dissolve its victim from the inside.
Then the striders take their time sucking out the innards.
Leaving the caddisfly a dried-out husk.
The stream delivers an endless buffet of new victims.
Because for most, that razor-thin line between water and air is a treacherous place.
But water striders know:
keep your feet dry and you'll always have the upper hand.
Hey there, it's Lauren.
I know you see that subscribe button there.
Here's what it'll get you - new Deep Look episodes every two weeks.
Keep up with all the weird, gross and wonderful things we're working on.
Thanks and see you soon.
-------------------------------------------
Sleep is a thought process - Duration: 4:04.
Welcome.
Now on to the next vrtti - sleep, the fourth one, sutra number 10. "Abhāva-pratyayālambanā tamo vŗittir nidrā. "
" Krishnamacharya added this word "tamas' here
to make it clear that in sleep the tamasic quality of the mind is very predominant.
In this context, there is a vast difference between samadhi and sleep.
Samadhi is a state where the sattvic quality of the mind is predominant and it's a state
of heightened perception.
We can even say mind is totally filled with sattva.
In the case of sleep, it is opposite.
It is [the mind] is in a state of darkness. In other words it's like being in a dark room
- objects are all there but, it is not seen.
Now, the question is 'how can sleep be considered as a vrtti?'
Vrtti is a thought, which is related to a knowledge. Patanjali stated a group of five
categories for nirodha, first is pramana - right knowledge, second is viparyaya - let's say
wrong knowledge, third is vikalpa - the knowledge that arises based on words without a corresponding
perceptible object, and now he has taken sleep.
On waking, there is a knowledge, or a vrtti, that arises about the state of, how the state
of our body and senses and our mind, were when we were asleep.
Therefore, we say when we wake up "I slept well, my mind is clear" if sattva is predominant.
"My mind was restless" if the rajas is predominant, "My mind is dull, my body is very heavy" we
say these types of statements when tamas is predominant.
Since sleep gives rise to these types of vrttis, which are related to body, senses and the
mind, sleep is also a vrtti for which nirodha should be done.
That is why the sutra here defines as - sleep is absence of waking and dream state.
In the waking state there is more sattva, in a dream state there is more rajas and in
the sleep state there is more tamas.
Nidra [sleep] that is mentioned here and yoganidra are completely different.
Yoganidra in a way is not a practice, yoganidra is a result.
Thank you.
Không có nhận xét nào:
Đăng nhận xét