Evolution and sexual reproduction

[kitkat]

I understand that if a species is separated by environmental barriers where enough changes occur in their DNA so that if both populations were to come together again they were no longer compatible for breeding. Correct? Why can humans that are separated by continents can still reproduce together?

[Ringer]

There wasn't enough time to cause humans to speciate between when they migrated out of Africa until they started interbreeding.

[Mr Skeptic]

Also, it's not so much the differences as the manner of the differences. If our chromosomes got rearranged interbreeding would become problematic.

 

Sometimes the changes that accumulate between the two populations aren't enough to prevent interbreeding. For example, the endangered species, European Wildcat, can interbreed with the common housecat (descended from African Wildcat). The species will probably go extinct due to this, although its genes won't and will instead become part of the housecat gene pool.

[Maximus Semprus Veridius]

We haven't been round long enough for our DNA to be radically different from one another so that we can't reproduce. I think around 2 million years or something??? Probably 3 or 4 though

[kitkat]

We haven't been round long enough for our DNA to be radically different from one another so that we can't reproduce. I think around 2 million years or something??? Probably 3 or 4 though

 

All of the large animals living today are not the same animals that lived with early humans. We have been around a lot longer then in comparison to other large animals.

[Maximus Semprus Veridius]

So?? I was saying that human's DNA has stayed similar enough to factions of one another to not be radically different. Other animals aren't really relevant. And also im fairly sure that most large animals 2 million years ago are the same or very similar to how they are now. You've gotta bare in mind that humans (Homo sapiens) have acctually stuck together for most of their history as well, we only established ourselves in the americas 10,000 years ago, and 10,000 years isn't long enough for realetively long lived animals to evolve in the wild, to the extent you are referring to.

[Ringer]

That doesn't mean that the large animals that were around with early humans when they started migrating wouldn't be able to produce offspring with animals now if they happened to mate.

[Darwinsbulldog]

I understand that if a species is separated by environmental barriers where enough changes occur in their DNA so that if both populations were to come together again they were no longer compatible for breeding. Correct? Why can humans that are separated by continents can still reproduce together?

With modern international air and sea travel, the gene pool is getting thoroughly mixed. I don't see a speciation event in our near future unless a population colonizes Mars or somewhere, then it could happen fast. I would like to be optimistic and say that racism is on the decline. However there is also religious segregation, but perhaps that is in decline too.

There has been a little evolution-stuff like lactose tolerance which has occurred in historical times. Mainly amoung people who domesticate herds and drink milk of course.

[kitkat]

That doesn't mean that the large animals that were around with early humans when they started migrating wouldn't be able to produce offspring with animals now if they happened to mate.

 

 

The larger megafauna that lived 10,000 years ago that is considered extinct do resemble modern mammals. I think that their previous appearance changed over time to reflect their current morphology traits today. This was obviously rapid evolution when we were busy inventing agriculture. It is harder to accept that a few small mammals are responsible for all the biodiversity of mammals when it is much easier to change the previous morphology of the biodivesity that defines that era of time into their current morphology that exists today.

 

By evolutionists that insist on saying 99% are extinct which are dead ends so modern humans do not feel it is a problem to wipe our current biota into extinction for selfish motives.The appearance of species in history makes more sense that changes in appearances occurred in the offspring over many generations with many original lines of descent from the beginning of their origin. Sure catastrophic events happened but they were never global to the point of wiping out all biodiversity with one sweep as we are doing today.

 

If I am right about this and we already caused the most massive extinction in the history of this planet by wiping out all mammals there is no chance for anything to evolve quick enough to fill their purpose in building a stable ecosystem. Nature's clues is the many species that can delay their reproductive cycles that can stop at specific stages in larvae and wait until conditions improve until advancing to the next stage of devevelopment. Frogs that can be frozen in time until it warms again. Fish that can be buried in mud clinically dead only to be revised with water.

 

Human beings that believe that we do not require the rest of the biodiversity to sustain the requirement for a stable global environment are signing their own extinction event. Science is advancing but they still don't have a clue of all the players involved in all of the biochemical processes that affects all the requirements to sustain life.

[Ringer]

The larger megafauna that lived 10,000 years ago that is considered extinct do resemble modern mammals. I think that their previous appearance changed over time to reflect their current morphology traits today. This was obviously rapid evolution when we were busy inventing agriculture. It is harder to accept that a few small mammals are responsible for all the biodiversity of mammals when it is much easier to change the previous morphology of the biodivesity that defines that era of time into their current morphology that exists today.

 

I don't know what this has to do with what I was saying

 

By evolutionists that insist on saying 99% are extinct which are dead ends so modern humans do not feel it is a problem to wipe our current biota into extinction for selfish motives.The appearance of species in history makes more sense that changes in appearances occurred in the offspring over many generations with many original lines of descent from the beginning of their origin. Sure catastrophic events happened but they were never global to the point of wiping out all biodiversity with one sweep as we are doing today.

 

First, almost all life that has been on Earth is now extinct has nothing to do with overpopulation, over farming, etc. Scientific consensus shouldn't have any large impact on morality of right and wrong. I have no idea what you are saying in your second statement.

 

If I am right about this and we already caused the most massive extinction in the history of this planet by wiping out all mammals there is no chance for anything to evolve quick enough to fill their purpose in building a stable ecosystem. Nature's clues is the many species that can delay their reproductive cycles that can stop at specific stages in larvae and wait until conditions improve until advancing to the next stage of devevelopment. Frogs that can be frozen in time until it warms again. Fish that can be buried in mud clinically dead only to be revised with water.

 

If you are right, do you have any sort of evidence to back up what you are saying besides a hunch, we haven't wiped out all mammals in any way, shape or form.

Human beings that believe that we do not require the rest of the biodiversity to sustain the requirement for a stable global environment are signing their own extinction event. Science is advancing but they still don't have a clue of all the players involved in all of the biochemical processes that affects all the requirements to sustain life.