A few questions about evolution

[Woodrow]

Can anyone explain to me how evolution works? Like an overview. Some websites are rather confusing...

To begin with and to clarify a few common misconceptions. Evolution has nothing to do with how life was created. Darwin never wrote as much as one theory of evolution. His book origin of species, was not a theory of evolution, it was a theory of how natural selection results in survival of the fittest.

Now with that out of the way there are 2 parts of evolution micro-evolution and macro-evolution. Micro-evolution is not a theory, it is an observable fact and is ongoing in each species. It is not about one species changing into another species, it is about all species that survive will develop the needed changes to survive in the environment. Appearances may change somewhat but it remains the same species. Cows are a good example. All cows are the same species and you can inter breed all of them. they all had the very same ancestors, kind of skinny brush eating creatures. But today's cows occur in a multitude of shapes and colors. Some are specifically heavy milk producers and some are heavy bodied meat producers. But they are all cows. That is micro-evolution. It is observable, replicable and does not conflict with creationism.

Macro-evolution is essentially all theory. It is a theory of all life coming from unicellular creatures and becoming all of the varied life forms we have today. This is the area of evolution that gets into the theoretical realm and is at odds with creationist concepts.

Hope that helps a little.

 

[IAmZamzam]

GuestFellow, suppose that a world-flooding torrent covered pretty much 100% of the earth's surface in water. Suppose it somehow happened overnight. Now let's say that before this flood two or three humans were, in one of mother nature's freak accidents, born with something vaguely akin to gills. They would be the ones likeliest to survive and repopulate. It's not that the flood gave them gills, it just made the gill people the obvious survivors. Their descendants would pretty much constitute the entirety of what used to be the human race. Indeed, in the process the gillmen might become more like The Gill Man, the further genetic anomalies which serve to help survival causing future generations still to become more and more like aquatic non-humans. It is possible that some of the original humans have survived all this time (or at least part of it), just like it's possible for the original white parents of a white child to still be alive once that child has grown up and started his own family with a black partner, the children becoming black within maybe one or two generations. And so on.

This is a fantastical example, I know, and I didn't even think of it myself, but with my limited understanding of these matters and my laziness it's the best analogy I have right now.

 

[GuestFellow]

To begin with and to clarify a few common misconceptions. Evolution has nothing to do with how life was created. Darwin never wrote as much as one theory of evolution. His book origin of species, was not a theory of evolution, it was a theory of how natural selection results in survival of the fittest.

Now with that out of the way there are 2 parts of evolution micro-evolution and macro-evolution. Micro-evolution is not a theory, it is an observable fact and is ongoing in each species. It is not about one species changing into another species, it is about all species that survive will develop the needed changes to survive in the environment. Appearances may change somewhat but it remains the same species. Cows are a good example. All cows are the same species and you can inter breed all of them. they all had the very same ancestors, kind of skinny brush eating creatures. But today's cows occur in a multitude of shapes and colors. Some are specifically heavy milk producers and some are heavy bodied meat producers. But they are all cows. That is micro-evolution. It is observable, replicable and does not conflict with creationism.

Macro-evolution is essentially all theory. It is a theory of all life coming from unicellular creatures and becoming all of the varied life forms we have today. This is the area of evolution that gets into the theoretical realm and is at odds with creationist concepts.

Hope that helps a little.

Thanks for the nice introduction.

One thing I am confused with. The term ''theory'' and ''fact.'' From my understanding, theory in scientific context means an explanation supported by evidence. Hypothesis is used to describe an idea in science. Are you suggesting that macro evolution is an idea/hypothesis or an explanation supported by evidence?

What does fact mean in science?

 

[Woodrow]

Thanks for the nice introduction.

One thing I am confused with. The term ''theory'' and ''fact.'' From my understanding, theory in scientific context means an explanation supported by evidence. Hypothesis is used to describe an idea in science. Are you suggesting that macro evolution is an idea/hypothesis or an explanation supported by evidence?

What does fact mean in science?

In science a fact is that which can be quantified, qualified and replicable. In other words you can measure a fact, see the unique identifying features, understand and know the processes that caused and and repeat the same processes with the same processes.

I have a hard time wording the definition of theory in my own word so I blatantly copied this from a web site:

As used in science, a theory is an explanation or model based on observation, experimentation, and reasoning, especially one that has been tested and confirmed as a general principle helping to explain and predict natural phenomena.

Any scientific theory must be based on a careful and rational examination of the facts. A clear distinction needs to be made between facts (things which can be observed and/or measured) and theories (explanations which correlate and interpret the facts.

A fact is something that is supported by unmistakeable evidence. For example, the Grand Canyon cuts through layers of different kinds of rock, such as the Coconino sandstone, Hermit shale, and Redwall limestone. These rock layers often contain fossils that are found only in certain layers. Those are the facts.

It is a fact is that fossil skulls have been found that are intermediate in appearance between humans and modern apes. It is a fact that fossils have been found that are clearly intermediate in appearance between dinosaurs and birds.

Facts may be interpreted in different ways by different individuals, but that doesn't change the facts themselves.

Theories may be good, bad, or indifferent. They may be well established by the factual evidence, or they may lack credibility. Before a theory is given any credence in the scientific community, it must be subjected to "peer review." This means that the proposed theory must be published in a legitimate scientific journal in order to provide the opportunity for other scientists to evaluate the relevant factual information and publish their conclusions.

SOURCE

 

[IAmZamzam]

In the specific parlance of science, a hypothesis is a working assumption, a theory is a commonly accepted assumption in the community which is intended to explain something, and a fact is a theory that is so thoroughly accepted that nobody even bothers to test it anymore. A question or guess you try the apparent veracity of when performing an experiment is a hypothesis; after enough of the hypotheses confirm the same thing their conclusion is seen as a theory in the community. Once all contrary theories have been dismissed and the idea in question is treated as a given (at least as a default), it is a fact.