Macroevolution

Help me understand this...

Alright so to me, this couldn't have happened. I don't have an alternate explanation, just don't think macroevolution has a very strong base. I'm not looking for a fight. I just want some sort of evidence for macroevolution. Microevolutionary shit won't be accepted in this thread.


Alright, so, when a rabbit eventually has an offspring that could be no longer considered a rabbit, how does it breed? I realize the concept is that these changes take place over millions of year, but there still needs to be a single change that would no longer classify the animal as a rabbit. Now I'm not sure I even understand how such a change could happen, but say it does. What does this new animal breed with? Wouldn't it be sterile? I mean if it could breed with the other rabbits, you could say it was just a changed rabbit. Thats all fine and dandy, but this type of evolutionary process would mean that today all animals should be able to breed with all animals. This simply isn't the case. I hope I worded this in such a way that you guys will be able to understand the gist of it.

Now, on to chromosomal differences among animals... How are these changed? I understand that mutations occur from time to time, but this typically leave the animal sterile. Now animals all have different numbers of pairs of chromosomes. Why? How? If the chromosomes split into extra pairs in a single animal, it would render the animal sterile. If the EXACT same split happened at the EXACT same time in enough individuals and for SOME REASON these new animals were able to mate, wouldn't the odds of their offspring being retarded mutants be sky high? If they weren't, isn't the gene pool a little small for this new species? The only explanation is that the vast majority of the population had the same chromosomal spliting. What would cause this?


I have many questions but start with these. I'm quite puzzled. I can't quite grasp the idea of macroevolution.

 

Very interesting. I'd like to know the answer to that too, my biology isn't as strong as my physics/chemistry.

 

You're acting as if this all happens over night.

Typically it can take millions of years, meaning the first animal showing mutations can still breed with the original species, and because it shares the same genetic structure, it can still breed. Because of the genes being passed down from the original mutation, there is now even more "mutants", meaning, with time, there is then a whole host of these animals with these genes.

I state again, it doesn't happen overnight, you seem to be acting as if it does.

Note that this "new animal" you speak of isn't really a new animal. See humans and gorillas, we share the same common ancestor, the genes just evolved differently over a very very long period of time. We surpass the gorilla in intellect, however they surpass us in brute strength.

Edit: Also note, when a Donkey and Pony breed, you get an Ass or Mule. Same genetic structure, different species.

 

As the genetic differences between animals grow, their ability to reproduce with each other shrinks. However, within a certain degree of genetic difference, they are still able to reproduce. For example, a brown horse can successfully mate with a white one.

Say a rabbit is born that has slightly longer legs than its peers. It can run a bit faster, and as a result, escapes predators that they cannot. Over time, the leg average for rabbits grows a little bit. This is now the "new rabbit". I know that is microevolution, but that is essentially what macroevolution is - the accumulated changes of millions of years.

This isn't my strong point, but I have found a bit of information:

http://www.talkorigins.org/indexcc/CB/CB141.html
http://www.google.com/custom?hl=en&...ins.org&q=chromosome+reproduction&btnG=Search

Essentially, chromosomes can fuse, yet still have all of the genes align. I would presume that they can split with the same result.

 

The terms macroevolution and microevolution both describe the same process.

No there doesn't. Numerous instances of microevolution can amount to macroevolution and speciation (and there's plenty of evidence for speciation). Basically what Shredderbeam said.