what are the theories of how life developed?

Answer 1

well...the bible says it was created in the span of seven days.

Answer 2

There are two major theories: Darwinism and Creationism. There is now a new theory called "Intelligent Design". Dawinism was started by Charles Darwin and his book, "The Origin of Species", which proposed evolutionary philosophies for both biology and society. It is still taught and respected in the scientific community. The basic focus is "Evolution by Natural Selection". Creationism is of course the theory of "Adam and Eve" and is more the Religious explaination. Science and Religion have been debating this issue for quite awhile now, and many scientists have turned to Intelligent Design to explain what Darwinism cannot. Darwinism explains many things, but is lacking in some areas. Intelligent Design, or ID, may be the meeting point between Darwinism and Creationism. ID says that in order for such complex structures, like the human body, to exist and function as perfectly as they do, there has to be a higher power involved (nowhere in the teachings does it address any god directly). There are also other theories about how the earth and all of the life on it came into existance, such as the Big Bang theory, but these are the main ones you will hear about in many debates and discussions. For more on these theories, check out the websites below, or ask a local biology teacher.

Answer 3

The development of life has one major theory: Evolution. There are some discussions of whether or not evolution occurred in fits and starts (Punctuated Equilibrium) or gradually over time.

Creationism is NOT a theory. It is religion. It is not science. Creationism/Intelligent Design has no testable theories and it has no statements that are falsifiable.

If you are wondering about theories of how life originated, there are really no robust theories yet. Mostly it is speculation, and a few plausible scenarios have already been suggested (not by any of the religious folk, however). Ignore the 'god of the gaps' arguments. They are a waste of time to anyone who wants to seriously understand their world.

Answer 4

Well, if you want modern-synthesis of evolutionary theory model ie: sience, then it would probably go something like this.

On early earth(as in a couple hundred million years after it formed) The atmosphere was made mainly of carbon dioxide, nitrogen, hydrogen, water vapor, ammonia, methane, and hydrogen sulfide. If you mix the latter 5 gases in a glass bubble(yes it has been done at Cornell University) and zap it with electricity and bathe it in ultraviolet light, then you'll end up with a brown sludge, at the bottom of the container. This brown sludge is just a mixture of a bunch of organic compounds. Many of these compunds, resemble proteins, and sugars. Many scientists believe that in the primordial earth, these compounds were formed in the sky, and fell to earth, dissolving in the oceans, where compounds began developing that could make copies of themselves, and life took off from there.

the other theory is basically the same, only with it all starting at thermal vents rather than in the sky. Chemically they both make sense, and evolutionarily they both end up with the same result.

All in all, the basic concept is that chemical evolution preceded genetic, or biological evolution. After maybe billions of chemical combinations the idea is that you will probably end up with at least something that can duplicate itself, albeit crudely, by using the billions of other chemical bits that surround it.

Good books for ''finding out more'' are Cosmos by Carl Sagan, companion to the 13-part TV series of the same name and copyrighted 1980. And Evolution, by Carl Zimmer, companion the 4 part PBS series of the same name. copyrighted 2000.

Answer 5

Two major conflicting accounts: The first is the Judeo-Christian account of creation in which God created man and life on earth. The second is the scientific evolutionary theory in which we evolved from earlier life forms.

Answer 6

the most accepted theory is the chemical theory or the naturalistic theory by OPARIN and HALDANE .the lightning struck, atoms combined to form molecules these came down with rain on the EARTH. In the oceans they further combined to form the complex molecules leading to the formation of certain bacterias which further slowly and slowly lead to the formation of reptiles,birds,animals and humans.It took 4500 million years.

Answer 7

There's the RNA world hypothesis:
http://en.wikipedia.org/wiki/RNA_world_hypothesis

Then there are these:
Miller, Eigen and Wächtershäuser's theories
"Metabolism first" models: iron-sulfur world and others
The Bubble Theory
Clay theory of the origin of life
"Deep-hot biosphere" model of Gold
All are explained here:
http://en.wikipedia.org/wiki/Origin_of_life

"Primitive" extraterrestrial life -- similar to the Panspermia hypothesis. These are cop-outs because they don't address how life started off the planet.
http://en.wikipedia.org/wiki/Panspermia

Answer 8

Lightning stuck the earth and mutated bacteria or something.

Arrived via star dust

Single cell organisms colonized into multi cellular stuctures. Such as coral, single cell organisms creating a aboitic structure then working as a whole to live life.

I took seven days to make it and 6000 years to screw it up.

Answer 9

GOD CREATED ADAM AND EVE AND THE WORLD IN 6 DAYS AND ON THE 7th DAY HE RESTED , EVALUATION -- MAN DERIVED FROM AN ANAMIAL . NOW BECAUSE THE GOD THEORY CAN NOT BE TAUGHT IN PUBLIC SCHOOLS , THEIRS ANOTHER THEORY OF AN INTELIGENT DESIGN .. I THINK THAT'S IT

Answer 10

two major theries :
1) science says, evolution
2) religion says , inteligent design and well god