Physics

» kaos42 - So...

In response to So... posted by BrianTubbs:
Theory in the scientific sense means a "body of knowledge", much like in the way that music theory is a set of facts and skills; it is not a hypothesis or proposal.

As far as evolution goes, it is accepted as fact by the vast majority of scientists. There is however debate over some of the details. One excellent example is the work of Lynn Margulis who has put forth the hypothesis that nucleated cells were originally the product of one non-nucleated single cell "eating" another but not destroying it. In this hypothesis, the internal nucleus was formerly a separate organism. The RNA of both organisms would have had to incorporate in order for both to reproduce together.

Margulis has also suggested that many of the internal organelles in "higher" life forms (animals, plants, and fungi) were acquired in this relatively simple manner. One very important acquisition for multicellular organisms was the microtubule organelle. The microtubule provides internal structure, and along with mitochondria, organelles that reside on the outside of the cell and metabolize oxygen for the cell, allow cells to live in large communities. The microtubule is also thought to play a part in the development of neurons, without which most animals couldn't exist.

There is resistance to these ideas because 1) they are difficult to reproduce in a controlled setting, and 2) many scientists are already entrenched with other views and dogma about the origin of complex life. This isn't bad - this entrenchment helps to test and poke and prod a hypothesis until everyone is satisfied about whether it is true or not.

If Margulis' ideas are correct, it would leave only one major question about how life might have automatically generated - why and how did RNA first begin?

-- posted by kaos42