Can someone explain this part of evolution to me?

Question

I'm not astute at these sort of dicsussion but just want some opinions.
If people evolved from cells or rock or whatever the begining source was how did that source have life? I mean even if it was a cell the cell had to be alive right so where did that life come from? At some point matter turned from non-living to living? I guess the confusing thing to me is how life can come from non life.

Answer 1

The short answer is: at this time, we don't know how life began in the first instance. It appears to have happened within the first few hundred million years of the earth's existence, and has almost certainly changed its basic form several times over the millennia (as from RNA-based to DNA-based). The original traces have been rather thoroughly scrambled by subsequent life as well as by the natural processes of tectonics and erosion, and I doubt that we will ever know the answer for sure. But if you've got a worldwide laboratory, and millions of years to experiment, strange things can happen. Once life began, evolution took over to create the enormous panoply of life that we see today. An excellent read on the earth's evolutionary history is:

Answer 2

For starters, the *real* scientific community doesn't use the terms 'macroevolution' and 'microevolution' at all. Those are from the Intelligent Design community instead. They're not distinct categories to scientists in the life sciences. It's like calling a single step "micro-walking" and taking a hike to the next county "macro-walking"--just a silly semantic game. Second, does the time period really mean anything? You can observe "micro-erosion" whenever you're watering a garden; it's just a matter of inference to realize that the same effect working over millions of years led to the Grand Canyon ("macro-erosion"). Third--and this is a moot point--you can't really 'see' gravity directly. You can only infer that gravity exists from the weight you feel on your body or from dropping a ball off a tower. Same with evolution and just about any other scientific theory out there. Hope this helps...

Answer 3

Its a bit complicated...

The origin of life is a necessary precursor for biological evolution, but understanding that evolution occurred once organisms appeared and investigating how this happens, does not depend on understanding exactly how life began.

The current scientific consensus is that the complex biochemistry that makes up life came from simpler chemical reactions, but it is unclear how this occurred. Not much is certain about the earliest developments in life, the structure of the first living things, or the identity and nature of any last universal common ancestor or ancestral gene pool.

Consequently, there is no scientific consensus on how life began, but proposals include self-replicating molecules such as RNA,and the assembly of simple cells.

Answer 4

Science has tried repeatedly to reproduce the conditions they believe life emerged from. These experiments have been total failures except in one case where a VERY simple protien was found. But keep in mind that this specimen was created in ideal conditions in a lab. The theory is that unicellular organisms formed in the sea, then life emerged from there. As a Christian, I am biased (of course), but if specialized scientists who devote their lives to this theory cannot produce more than a building block for a cell, a single brick in a skyscraper as my metaphor would be, how can anyone believe that a cell with an extremely complex DNA structure and the ability to reproduce itself could macro-evolve into something as miraculous as the human being?

Answer 5

There is no truly "standard model" of the origin of life. But
most currently accepted models build in one way or another upon a number of discoveries about the origin of molecular and cellular components for life, which are listed in a rough order of postulated emergence:

1. Plausible pre-biotic conditions result in the creation of certain basic small molecules (monomers) of life, such as amino acids. This was demonstrated in the Miller-Urey experiment by Stanley L. Miller and Harold C. Urey in 1953.

2. Phospholipids (of an appropriate length) can spontaneously form lipid bilayers, a basic component of the cell membrane.

3. The polymerization of nucleotides into random RNA molecules might have resulted in self-replicating ribozymes (RNA world hypothesis).

4. Selection pressures for catalytic efficiency and diversity result in ribozymes which catalyse peptidyl transfer (hence formation of small proteins), since oligopeptides complex with RNA to form better catalysts. Thus the first ribosome is born, and protein synthesis becomes more prevalent.

5. Proteins outcompete ribozymes in catalytic ability, and therefore become the dominant biopolymer. Nucleic acids are restricted to predominantly genomic use.

Answer 6

There are various theories on how this happened. You should do some research on the term "abiogenesis" to see. Basically, all the ingredients for making amino acids were present on early Earth. Despite the low probability of a single reaction randomly producing an amino acid chain, the sheer number of chemical reactions actually gives a pretty high probability of life spontaneously arising given enough time.

Answer 7

The study of how life first formed is called abiogensis. The idea is that non-living matter can create basic life that eventually evolved into single celled organisms. The first part of this has been done in experimentation.

Answer 8

It is a matter of definition. What constitutes life. There are entities, such as prions, that do not conform well to our definition and so there is difficulty classifying them as either alive or not. Organic molecules are not static. They do move and react and do things. They are not considered life until they perform all of the things required by our definition (reproduce for example). As they become more complicated and do more things they can eventually cross the border. The molecules won't recognize a difference cause they do as they do. The problem is the arbitrary nature of the definition. Change that and you have a whole new system of living things.

Answer 9

Well Bruce I'm a mere atheist and not a evolutionary biologist but from what I understand that is not evolution but abiogenesis.

Unlike evolution (which has theory status, significant in a scientific context) it is hypothesis.

http://en.wikipedia.org/wiki/Abiogenesis

We don't know yet. It happened a long time ago and it was very simple (life would have exceedingly simple origins) and traces are hard to find there. But we have some interesting ideas, and people are working on it.

Answer 10

The theory of evolution says nothing about the origins of life.

Evolution is not a replacement for Creation, which is why I don't understand why religious zealots get all hot and bothered by evolution.

I don't know where life came from, no one does. The difference is that some people call this unknown God.