first life forms?

evolution vs. migration. that's a totally different thing dude. about as far as philosophical as you can get too.

people live now where they live for no other reason than socio-economic reasons. there are people on this board that's lived the world over - aversion comes to mind. explain that.

evolution of a species in some cases is necessary to help that species become better at living in that environment. cactus maintain water because of their location. they are unlike most other plants.

dude, in this case, evolution via successful mutation is the key here. if it's something that's unsuccessful, say like an albino gecko - which happens - then that species can't do things like be out in the sun. so, it becomes nocturnal. and who knows... it may catch more bugs in the night... next thing you know, it has the strength to reproduce, and share that albino gene with future iterations.

next thing you know... it's a fact that more albino gecko's are the norm, not the mutant.

I used gecko's because there's one that seems to love my pineapple plant at night.

ok, some believe life is extraterrestrial. That a meteor came to earth and life began. Possible, but hard to prove.

Most scientist kinda agree that if there's water there's life. Meaning: without water there's no life (from an economical point of view, there are theories that state that water is going to be the most valuable good in the future, more than gold or oil. Somewhere in the future, the world is suppossed to turn into a water based economy....just a theory though).

Anyway, that believe is due to the forms of life that live on earth. However some scientist discover a bacteria that feeds and breathes and live inside an enviroment where is supposed to be impossible to survive (inside some volcanos underwater), which has lead some to think water isn't necessary for life.

However, now, with theories of the existance of water in mars, scientist due believe there's the chance of the existance of life (primitive life) over there.

regarding evolution. It's not a matter of desire, it's a matter of necessity. As Charles Darwin said: "only the strong will survive". If you take away the technology advantages that exist nowadays, you still can see that men have evolved. Now they are taller, stronger, run faster, etc, and with the help of technology, we've artificially evolved a lot more.

Now if you see, evolution is developing what you need and dropping what you don't need. Coming to the galapagos islands (the place where charles darwin started working his theory), you can see how the same animal (turtles) is different in each island (cause there, each island is a world). In one island some turtles have really long necks, due to the fact that they need to feed of the leafs of trees (there's no grass in that island). In other island they look different, according to the needs they had to survive. There are some birds that literally have lost the ability to fly (the most known ones: pinguins) but can swim almost like a fish...why? cause in the environment they live in they have the necessity of feeding from fish....they develop they ability of swiming and wings were useless.

Under that same theory, people think that birds are new improved dinasours (again, theories, but if you look at a dinasour bone structure, and then at a bird's bone structure, they are quite similar. That's why some scientist believe dinos had feathers, and not a skin like a crocodile).

Now, in the word's of one of my favorite bands (TOOL): life feeds on life feeds on life.

It's to create a balance. That's why introducing a new species in an habitat is so dangerous (like frogs i believe in Australia, or cats in the galapagos) cause they unbalance the system.

Another case of evolution: humans do have trace of a very primitive tail :D serious....you have a tail, but as we don't need it, it's soo little it doesn't show up (unless your a mutant). Appendicities, what is it? the inflammation (is that expression correct?) of an organ that has reduced almost to nothing, but still exist in ourselves, although we don't use it at all. Some animals need it and use that organ, we don't....evolution.

I keep seeing things like 'evolution is based on necessity'. I think you may have the right idea, but are using the wrong words. Variation is a much better word to explain evolution. Here's a simple breakdown of evolution. Using a turtle's neck being longer than other turtles as an example.

A group of turtles are living on an island. It wouldn't be uncommon to see the necks vary in length from one turtle to the next. Now, the food situation on this island is, a lot of food high up and a little food down low. The turtles with the longest necks can reach the abundant higher food as well as the lower food, but turtles with shorter necks can only reach the lower food.

Most of the food gets eaten in the lower area since all the turtles are eating it, so some of the shorter necked turtles starve. The turtles have offspring and there is now a larger majority of longer necked turtles than shorter necked turtles because most of the longer necked turtles from the previous generation survived while a good part of the shorter necked turtles of the previous generation starved.

There is still variation in the new generation of turtles, but now there isn't as much food for the shorter necked turtles to eat, so after many generations, the population of turtles tends to have longer necks than they used to. This is because of the variation inherit in life. The turtles with longer necks survived because they could reach all the food, while some of the shorter necked turtles starved to death each generation. There were more longer necked turtles that mated and had baby turtles with longer necks, but there weren't as many shorter necked turtles aroung that could mate and have babies with shorter necks.

There are many other ways that a species could change over time, but it usually ends up due to variation in the species.

j

good example, yasunobu13. I agree 100%.

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Originally posted by gerbick
good example, yasunobu13. I agree 100%.

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I learned from this guy, Packer

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Packer Receives National Honor
Craig Packer, Distinguished McKnight Presidential Professor of Ecology, Evolution, and Behavior, has been elected a fellow of the American Academy of Arts and Sciences. The academy is an international society that promotes service and study of social, scientific, and intellectual issues. Packer, an internationally known expert on animal behavior and evolution, has been a member of the University faculty since 1983. Also elected this year were 4 Pulitzer Prize winners, 3 Nobel Prize winners, Bill Gates, Kofi Annan, and Walter Chronkite.

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Originally posted by gerbick
good example, yasunobu13. I agree 100%.

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As for life comming from outerspace, durring the whole SARS epidemic one scientist said that it could have come from an Astoroid, and that every year there are some asteroids that hit our earth that carry bacteria with them...now that lady might not have known what she was talking about, but if she did then I think that prooves there is life out there.


Yea, your "tail bone" is actually a remenant of a tail.



I have hear theroies, that state our current (will, at least the USA's) problem with obisity stems from the "Survival of the fittest" scenario, because only the people that were able to pack on the pounds were able to survive through famins, and food shortages...and now that we have an aboundance of food in the states that genetic trait causes problems rather helps them the people live through the famins.

By the way, I just wanted to congratulate everyone in this thread for keeping it on track, and not turring it in to a flame war...I wish all discussions on FK were this civil and well carried out.

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Originally posted by onlinegs.com
I have hear theroies, that state our current (will, at least the USA's) problem with obisity stems from the "Survival of the fittest" scenario, because only the people that were able to pack on the pounds were able to survive through famins, and food shortages...and now that we have an aboundance of food in the states that genetic trait causes problems rather helps them the people live through the famins.

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naw. more like too much fried food, television, internet, and not enough outside play.

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Originally posted by gerbick
naw. more like too much fried food, television, internet, and not enough outside play.

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I agree, that plays a big part, but there are some of us (like my mom and I) that can practically eat what ever we want without a problem while others have problems.

I am also not talking about the kids that have weight problems, but more the 25 - 55 age group

Survival of the fittest does not apply to humans based mostly on technology.

As for SARS being bacteria from an asteroid, I'm pretty sure that SARS was a virus, wasn't it?

On an interesting note, the current theory on how viruses originate is that they are mutated genes from the species that they infect. That's why viruses tend to be species specific and that nearly every living thing is susceptible to viruses.

j

talking about virii, check out this huge one... :eek:

such a big virus with such a funny name

Mimivirus

is it named after that annoying Drew Carry character?

j

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Originally posted by yasunobu13
Survival of the fittest does not apply to humans based mostly on technology.

As for SARS being bacteria from an asteroid, I'm pretty sure that SARS was a virus, wasn't it?

j

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The quote was probabably something like "we are constantly bombarded by bacteria and virus's from outer space". I heard it thid person, so I never got the exact quote.

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Originally posted by onlinegs.com
The quote was probabably something like "we are constantly bombarded by bacteria and virus's from outer space". I heard it thid person, so I never got the exact quote.

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well, you have to analize, research and get your own conclussions. You know, there are theories that say that AIDS was created by the CIA....

Viruses are just wonderfull. You see how one of the most common diseases comes from a virus (the flu ["gripe" in spanish]). Amazingly you get sick over and over again. Why? cause the virus is always mutating....so actually you never get infected by the same virus, but by a mutation of it. Interesting, right? i think the same happens with AIDS(it mutates)(of course you just get that once).

And if you analize a little bit: pc-viruses are the closest thing to artificial life that humans have created (cloning is not creation, just reproduction, and maybe mutation)....but a software virus, acts exactly as a living virus.

I know that is what the scientist said, I am just not sure on an exact quote, and I never said I believed her, I just repeated what I heard.

Yes, the AIDS virus does mutate, thats why we have as of yet been unable to come up with a vaccine for it.

uhmm i think i asked this before on this forum but i never quite get it,
what is a virus exactly? can we really classify it as a living being? have they always being here even before animal life forms?
also i know that plants can get sick but are they effected by virus too?

also it looks to me that the smaller a living thing is the faster mutates (or evolve if you will) am i right or wrong?

oh yes one more thing i wanted to ask you guys

do you believe that life started from a specific location on the planet
or like i believe it just spread all over almost simulataneously??

this should be a long one

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Originally posted by magnetos
what is a virus exactly? can we really classify it as a living being? have they always being here even before animal life forms?
also i know that plants can get sick but are they effected by virus too?

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I answered this in a previous post a week or two ago, but I can't find it anywhere now.

I'll go into depth with this one.

virus (from my biology book) - A tiny pathogen composed of a core of nucleic acid (DNA/RNA) usually encased in protein and capable of infecting living cells; a virus is characterized by total dependence on a living host.

it is undecided if viruses are alive or not. There origins are much different than that of any other living thing on earth, as are the way they behave. go here and decided for yourself.

http://www.beyondbooks.com/lif72/2c.asp

how a virus works -
1) a virus attaches itself to a host cell
2) The virus injects the nucleic acid into the host cell
3) The virus then uses the host cell to aid in the replication of the virus
4) The viruses use the protien from the cell to encase themselves
5) the viruses leave the host cell, usually destroying it in the process

It has been shown that most viruses are closely related to the species that they infect. In fast, most viruses are species specific. Because of theses and other reasons, it is believed that viruses are actually mutated DNA/RNA from an animal of the species that it infects.

Since viruses are actually created from the living organism that it infects, then it also likely that viruses have been arounf for as long as life has been, but not before life.

Even plants have viruses, but since they have very think cell walls, it is more diffucult for them to be infected in ways other than reproduction.

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Originally posted by magnetos
also it looks to me that the smaller a living thing is the faster mutates (or evolve if you will) am i right or wrong?

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In an earlier post in this thread I said that most evolution is caused by variations inherit in life forms and how the apecies can be affected by variations and the environment. Any real evolution of a species takes many generations. Mutations aren't the main cause of evolution, even though mutations are the only way for varying differations between species (gills vs. lungs, plant vs. human) they usually aren't noticeable or benificiary to the mutated individuals. Only if the matated gene is able to be passed on would the mutation be able to persist, but until it allows those with mutation to survive in situations where the unmutated indivdual may not survive, species don't really evolve. (that was phrased poorly)

As for smaller organisms evolving quicker, it's a matter of generations again in order for the species to change somehow. Size is not the issue, reproduction is. It's a tendency that smaller organisms have shorter life spans and need to reproduce quickly in order for the species survive, but that does not guarentee evolving or mutations that become benificial.

it is only through small changes that evolution happens

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Originally posted by magnetos
do you believe that life started from a specific location on the planet
or like i believe it just spread all over almost simulataneously??

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The following is a summation of the a current theory about the beginning of life on earth:

First, it is believed that life originated from non-living material in an earth that is much different from today's. Also it is believed that life originated only once.

The atmosphere of early earth was made of carbon dioxide, water vapor, carbon monoxide, hydrogen and nitrogen with little to no oxygen available.

There are four things needed for chemical evolution:
1) little or no free oxygen (it would have oxydized the necesary building blocks for life, thereby making them useless)
2) a source of energy
3) the availability of chemical building blocks
4) time

There are two theories on how life could have formed in this environment.
1) simple organic molecules could have formed spotaniously from raw materials. It has been shown that an environment similar to what is bilieved to have been the conditions of early earth, when exposed to an electrical charge, produces amino acids and other organic molecules. This is the primordial soup that you may have heard about.

2) polimerizations leading to the origin of life could have formed near hydrothermal vents at cracks in the earth's surface at the bottom of the ocean.

Once these ploymers have formed they could have assembled into more complex structures called probionts, which are basically the inbetween stage when goind from a polymer to a cell.

eventually cells were created and were made of nucleic acid. The nucleic acid eventually formed into RNA, which eventually formed into DNA.

The earliest lived off of absorbing other cells as there is no cell that had the ability to use the energy from the sun. The first cell to use energy from the sun was cyanobacteria. When cyanobacteria started using the sun as it's form of energy, it was the only organism that could, so it thrived immensly. So much so, that it filled the atmosphere with oxygen (the byproduct from photosynthesis). Since most living things on earth at the time had never been in contact with oxygen, nearly all life on earth was wiped out.

Eventually cells absorbed other cells, but didn't digest them. This is how plants came to be. A cell absorbed a cyanobacteria, but did not digest it. The absorbing cell now got energy from the cyanbacteria and the cyanobacteria was now protected by the other cell. This is also how mitochondria came to be in our cells. It used to be another living thing, until one cell absorbed it without digesting. After many generations of this sort of behaviour the two cells could not live apart and became one organism.

I hope the above answers your questions somewhat.

j

let me just say... wow.

I learned something tonight.

:D

thanks yasunobu13 that was a great explanation i think i actually understand it :)
thanks to the other guys too ofcourse :)

ps

is this bleh !! thing contagious? :D

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Originally posted by magnetos
is this bleh !! thing contagious? :D

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apparently! I never noticed that others had my bleh! speech balloon... too funny! :D