much time we have. What's the oldest a person can ever be? Well, the world record for the

world's longest living person belongs to Jeanne Calment, a French woman who lived to be 122.

Right now, at this very moment, there are only 37 people alive who were born in the

1800's. Those 37 people have lived in three different centuries. But, as medical knowledge

expands and our understanding of biology improves, people are living longer, and longer. In fact,

scientists believe that, based on statistics, the first person who will ever live to be

150 has already been born- it could be one of you. But, according to the math, it's probably

someone who was born last year.

Here's the thing- as humans get older, the likelihood of them dying increases, but there

are some types of animals who have what is called Negligible Senescence, also known as

biological immortality, and these types of animals have never been observed to actually

age. Animals, like the Hydra, can only die because of accidents, disease, or predators.

The world's oldest living individual tree has clocked in at more than 4,600 years old.

It's called the Methuselah Tree and it exists somewhere in this forest. Government officials

won't actually release its exact location to protect it from vandalism, but it's out

there.

The lifespan of an organism can be even longer than that if you include clonal colonies.

For instance, these Quaking Pines all look like individual trees, but they're actually

all clones of one genetic code. They all share a root system, and the root system continues

to make more trees, meaning that these trees are all part of the same organism, and experts

have calculated, based on the roots system, that this one, male Quaking Pine has been

around for at least 80,000 years.

But, let's get back to humans, and rather than talking about how is, let's talk about

how time feels. Intense moments of your life are remembered as lasting much longer than

times that were relatively dull. Psychologists say that the reason for this is that our brains

take deeper, and richer memories of events that are novel, or events that are intense,

than ones that aren't.

When your experiences are intense and novel, you're not remembering more things about it,

but you are making more copies. Rather than just making normal memories, during stress

the amygdala gets involved and also remembers things, and many people believe that is why

intense moments are remembered as lasting longer.

This phenomenon becomes quite mind-blowing on a macro-scale. Think of it this way: when

you are a one-year-old baby, one year represents 100 percent of your life, but when your turn

two years old, that second year was only half your life, and the next year you live through

is only a third of your life, and by the time you turn 80, one year only represents an 80th

of your life. Those percentages are important because they may explain why your childhood

feels like it took so long, but as you get older, the years seem to fly by.

You have more novel experiences when you're young- you first learn a language, you first

see your mother, you first learn to walk, you have your first kiss- these are all deeply,

and richly remembered by your brain, and so, later on, it feels as if they took longer

to happen.

Now, here's what's really mind-blowing. Let's look at a graphical representation of the

percentage of your life that each successive year is. The first year is 100 percent, the

second year is only half, the third year is a third, and so-on will go all-the-way out

'til 80. Now, using this representation, under this model, when you turn 80 years old and

look back at your life, the point that feels like the middle isn't your 40's, it's your

early 20's.

The good news here is the more novel things you do, and things you see, and places you

visit, and people you meet, the slower time feels, and the more rich it feels. So, go

out there and do something cool, do something weird, do something new- subscribe to Vsauce

if you haven't already! And, as always, thanks for watching.