Evolution question - 'Dollo's law'?

Question

Is this law important to evolution? I'm biased, in that I don't believe evolution trumps Biblical creation.

But the question is, can complex structures (life forms) re-evolve? If I understand 'Dollo's law', complex structures can't '...because the genes that code for them have either been lost or have mutated.'

Does it make any difference?

Just read an article in 'Science Daily' about 6 kinds of sea snails in South America that evolved, then 're-evolved' (devolved?) to an earlier stage, then evolved again.

Isn't it possible that this same gene sequencing and re-sequencing may happen in any species?

'Sea Snails Break The Law' - Smithsonian Tropical Research Institute 4/26/07

Answer 1

Dollo's Law is merely a hypothesis, and a poorly supported one at that. Much evidence has shown that the 'junk' DNA is actualy old or disabled genes, that are therefore availible for future 'reversions' as needed.

For example, we are currently losing our appendix, evolutionarily speaking. If the gene is 'lost' because it migrates into our 'junk' DNA and loses its switch, then we will lose the appendix. However, because the information is still there, if later a mutation reconnects it to a regulatory switch, the appendix might reappear later.

If we somehow as a species moved to a predominantly vegetarian diet, the re-emergence of the appendix would be highly advantageous, and one would even expect to see this happen.

Frankly, I'd say Dollo's Law is inconsistent with the modern knowledge of genetics.

Answer 2

Unless genes are merely repressed or deactivated in someway, they cannot return later down the evolutionary path.

An example of a repressed gene re-expressing itself is seen in chickens where they can grow reptile teeth due to mutation. These genes likely date back to before the therapod/avian transition but were repressed due to the development of a beak.

As for the Sea Snails bit you mentioned - I'm not sure whoever wrote the article knew what they were talking about but it's more likely that the different breeds/species developed from a common ancestor rather than from each other so the genes would have all come from the same source but were dropped during speciation.

Answer 3

Judging from the definition of Dollo's Law, it appears its simply stating that body plans cannot reverse in form.

On a small scale, this claim is not correct. In Phylogenies we see many times the loss and regain of traits in ancestral lineages.

However, its interpreted by current Evolutionary Biologists in different ways. For example:

"According to Richard Dawkins, the law is "really just a statement about the statistical improbability of following exactly the same evolutionary trajectory twice (or, indeed, any particular trajectory), in either direction." [1] Stephen Gould viewed the idea less strictly, suggesting that "irreversibility" forcloses certain evolutionary pathways once broad forms have emerged: "[For example], once you adopt the ordinary body plan of a reptile, hundreds of options are forever closed, and future possibilities must unfold within the limits of inherited design."[2]"

http://en.wikipedia.org/wiki/Dollo's_law

I don't think this hypothesis is a major component of Evolutionary Theory. It mainly interpreted today as a statment of self-evident facts about the development of organisms and the statistics of reversing lineage directions.

Answer 4

It's not a particularly critical. It's basically a statement that a lost structure reemerging is effectively impossible from a statistical standpoint. Dollo died in 1931 and was unaware of molecular genetics. Given the nature of homeobox and other developmental master genes, I'd consider the likelihood of structures reemerging low, but not so low that it could not have occurred.

Answer 5

Until Creationism can explain the observable FACT that new species have replaced earlier species ever since life appeared on earth, biological evolution is the only show in town. Such a complex and wondrous system surely gives glory to the One Who designed and created it. The Bible tells us that after the initial creation, God "rested", that is, stopped creating. Apparently "creationists" would deny the Word of God and claim that God has continued creating new species regularly for billions of years - and curiously, always species quite similar to those that lived just a little earlier.
.

Answer 6

I have been studying evolution, and I haven't run across Dollo's law so I don't know. I am very skeptical of any new feature ever evolving from a genetic mistake, like an eye or a brain or even blood evolving from creatures that had no such things.

Answer 7

No The thing is Darwin's theory has been proven wrong by the scientists. Read Forbidden Archeology, and the Hidden History of the human race By Michael A. Cremo. There are heaps of archaeological findings that prove man was way more intelligent in every way even millions of years ago and they didn't look like apes or cavemen. It is in alignment with the original Vedic Knowledge. (the original scriptures that came with the creation). It is actually evolution of the soul not the body.

Answer 8

revovle??? i guess that means become less efective at surviving than more since that is all evolution is. Then no because as i undertand it in 9th grade undesirable traits would die off and be lost.

ahh yes wisdom we would be foolish not to think that science is crushed by 2000 yr old books written by people who misunderstood large portions of their world. Unless you being sarcastic in which case, well put

Answer 9

That is the problem with Science. It's the religion of "change the rules at any time" The bible is solid in what it teaches. Two thousand years from now it will still say God created man.

Answer 10

Dollo's law is very close to a scientific failure.