The " I always wondered" thread

[DAVOUT]

Originally posted by Urban Ranger


That is not correct. Even though by 25 a lot of individuals probably have good chances to pass along genetic information, the catch is humans are k-strategists. That means humans give birth to a few offspring, but we rear them well. On the flip side are the r-strategists, which makes a lot of babies. You can see that the highest forms of animals (birds, mammals) are all k-strategists, that means they need a lifespan long enough to rear their young too. I'd say that put at least the natural lifespan to 40 years.

I was comparing comparable figures : the 80 years mentionned in the original question is the life expectancy, and should therefore be compared to the natural life expectancy in my reasonning. As I said above, the 25 years of average life expectancy does not preclude the existence of enough adult to rear the living youngs.

[Ari Rahikkala]

Originally posted by Boshko
Also the way humans evolved was to become more childlike (there's a scientific word for this process that eludes me), that's why we are less hairy, better at learning, and have a bigger brain:body ratio just like chimp babies compared to adult chimps. That's also part of the reason why we're weaker.

Neoteny.

[Juggernaut]

What is the definition of equations which can only be solved numerically? Or is it arbitrary?

[OzzyKP]

So life span is directly tied to reproduction?

How does this work in the 200 year old tortoise?

Heck, even trees that live a thousand years. They reproduce hundreds of times. Of course there are more differences between plants and animals, but why do we have to break down? Why don't our cells just continue to repair themselves for a thousand years like Redwoods?

[DAVOUT]

Originally posted by OzzyKP
So life span is directly tied to reproduction?

How does this work in the 200 year old tortoise?

Heck, even trees that live a thousand years. They reproduce hundreds of times. Of course there are more differences between plants and animals, but why do we have to break down? Why don't our cells just continue to repair themselves for a thousand years like Redwoods?

Just a few guesses for the tortoise (knowing that the 200 years is probably not the average life expectancy, and by far):
- considering the enormous losses due to predators of the eggs and young tortoises,
- and considering also the necessity that the descent result from many different mates (tortoises make eggs once a year ?)
it could take that kind of duration to be sure to get a viable descent.

The idea is identical for the trees, with a reproduction system more complex in that it demands the help of elements outside the trees such as winds or insects, and therefore still more time.

Why do we have to break down ?

Life is a replication system; any living form, once it has replicated enough to ensure the transmission of its genes, is designed to break down and die through degeneration. That process makes room and material for more life.

[Urban Ranger]

Originally posted by Kropotkin
There's nother thing I've noticed that I think more than americans have but I still haven't figured out what it's for. In the sink there seems to be some sort of grinder down in the hole. What's the point of that?

You can throw organic stuff (probably not bones though) such as bits and pieces you peel off when preparing a meal down the sink, then turn on the grinder with water running so all that stuff you thrown down won't clog up the drainage.

[Hot Mustard]

Why is common sense so uncommon?

For example, everyone finds it annoying to have to walk around people who are standing still (talking on their cellphone, chatting with someone they ran into) in a high density area. Yet almost everyone does this very thing at some point. If I meet someone I'd like to chat with in a public place, I suggest we "pull aside", so as not to become an obstruction.

There are countless other situations like this, both minor and major in impact. I really think the phrase should be renamed "uncommon sense".

[Az]

I've always wondered:

Our entire galaxy is moving. wouldn't that mean that that inside the solar system, light would go slower one way than the other?

( I can't wait to get to Relativity in uni, finally, it will all be explained. )

[Eli]

Originally posted by Azazel
I've always wondered:

Our entire galaxy is moving. wouldn't that mean that that inside the solar system, light would go slower one way than the other?

( I can't wait to get to Relativity in uni, finally, it will all be explained. )

Light speed is constant, whether you move at any speed or dont move at all.

[Az]

I know, it's hard for me to comprehend.

[Koyaanisqatsi]

I always wondered what language people who have been deaf since birth think in. When most people think, it takes an almost verbal/auditory form in their mind...but the deaf wouldn't have anything to base that on.

[Eli]

Continuing Azazel's question... What's the explanation to this?

If I travel at 0.99c in a certain direction and a lightwave travels at c in the same direction I will measure it's speed as c, right? But why? Is it because the time dilation that I will experience?

[DAVOUT]

Originally posted by Azazel
I know, it's hard for me to comprehend.

The speed of light is constant, but the observer situated on the way the solar system is moving will receive sooner the light originated in the part of the solar system closer to him than the light originated in the farther part, since the former light will have a shorter distance to run.

[Az]

yes.

[mapfi]

Originally posted by johncmcleod
Why do hot dog packages come in 8 and the buns come in 6?

And why do Germans in the movies yell "Halt!" for telling people to stop? This would be the correct command for the familiar form, but Germans in this situation would definitely talk in the formal. They would say "Halten Sie!"

No, they would not - the movies are tight at this for once... I guess the reason is that "halten sie" would be longer plus when you command someone to stop you don't care about the formal form anymore