Speciation in humans

[StringJunky]

As the human population becomes increasingly interconnected with fewer isolated communities, does the possibility of future speciation disappear? Is geographical isolation a necessary condition of speciation?

[The Tactical Strategist]

No, but there would have to be a dramatic change. Maybe a extreme change of weather in some part of the world

[swansont]

Depends on what you mean by speciation. If humans survive long enough, there may be enough change that you could consider them a new species. Branching is not necessary — you can have isolation along the time axis as well. We are a distinct species from our Homo ancestors.

[StringJunky]

Depends on what you mean by speciation. If humans survive long enough, there may be enough change that you could consider them a new species. Branching is not necessary — you can have isolation along the time axis as well. We are a distinct species from our Homo ancestors.

They'll not co-exist in the same timeframe though will they? Nevertheless, I think you are right; speciation can still occur.

[Wolfhnd]

There is also genetic engineering which could result in speciation.

[swansont]

They'll not co-exist in the same timeframe though will they? Nevertheless, I think you are right; speciation can still occur.

 

No, they wouldn't, and there would be no single instant that you could say speciation had occurred. But of humans survive another couple of million years, it's possible.

[Greg H.]

In general, yes, I think the human species could diverge.

 

Personally, and this is simply an opinion, but the science seems sound, I think the next big speciation event for humans would occur after we finally move off Earth on a permanent and long term basis. Given enough time, and separation, diverse populations on diverse bodies could tend to develop more in line with the body they live on - adaptations to gravity, solar radiation, light levels, etc.

 

But again, this would require both a mutation and a selective pressure maintained over time, to realize.

 

Or genetic engineering.

Edited February 19, 2015 by Greg H.

[StringJunky]

In general, yes, I think the human species could diverge.

 

Personally, and this is simply an opinion, but the science seems sound, I think the next big speciation event for humans would occur after we finally move off Earth on a permanent and long term basis. Given enough time, and separation, diverse populations on diverse bodies could tend to develop more in line with the body they live on - adaptations to gravity, solar radiation, light levels, etc.

 

But again, this would require both a mutation and a selective pressure maintained over time, to realize.

 

Or genetic engineering.

Yes, there are possibilities for speciation to occur with future space colonies ...never thought of that one.

 

No, they wouldn't, and there would be no single instant that you could say speciation had occurred. But of humans survive another couple of million years, it's possible.

Yes, evolution is a continuum. This is where most deniers seem to get it wrong; they think it's a step-change.

[starlarvae]

Yes, evolution is a continuum. This is where most deniers seem to get it wrong; they think it's a step-change.

Hmmm . . . . I thought "speciation event" was standard terminology.

Yes, there are possibilities for speciation to occur with future space colonies ...never thought of that one.

 

Speciation in space colonies? Never thought of that!

[CharonY]

Hmmm . . . . I thought "speciation event" was standard terminology.

 

 

It is, but I assume you are misinterpreting it. It does not mean a sudden jump. The nomenclature is (I think) derived from nodes in a tree where a split has happened. However, while it is a point in a diagram, the actual event takes place over a long time and is gradual (which is some trees is indicated by branch lengths, for example). So the speciation happens over the time of two branch openings, so to say.

Edited February 19, 2015 by CharonY

[StringJunky]

 

It is, but I assume you are misinterpreting it. It does not mean a sudden jump. The nomenclature is (I think) derived from nodes in a tree where a split has happened. However, while it is a point in a diagram, the actual event takes place over a long time and is gradual (which is some trees is indicated by branch lengths, for example). So the speciation happens over the time of two branch openings, so to say.

Speciation event is probably one of those - misunderstood - expressions that causes novices to think it is a step-change in evolution. A bit like 'Big Bang' causes people to think of the inflationary epoch as an explosion in space.

 

What do you call the evolutionary process where a species diverges (by virtue of geographical separation) concurrently into two more as opposed to over a long time in single sequence and the old species dies off first?.Actually, knowing the names of both would be good.

Edited February 19, 2015 by StringJunky

[Wolfhnd]

Speciation is one of those pre genetics hangovers

[starlarvae]

Speciation event is really speciation "event." Sort of an event, but not really. More like an ongoing process. (The literal event occurs when the taxonomists say it does.)

Natural selection is really natural "selection." Sort of like selection, but not really. More like wait and see what happens (i.e., see how distribution of reproductive success yields trait distributions among offspring)

Selection pressure is really selection "pressure." Sort of like pressure, but not really. More like wait and see what happens. . . .

 

Why is evolution theory so mealy-mouthed, so reliant on metaphors? Why can't it just say what it means, literally?

[swansont]

Speciation event is really speciation "event." Sort of an event, but not really. More like an ongoing process. (The literal event occurs when the taxonomists say it does.)

Natural selection is really natural "selection." Sort of like selection, but not really. More like wait and see what happens (i.e., see how distribution of reproductive success yields trait distributions among offspring)

Selection pressure is really selection "pressure." Sort of like pressure, but not really. More like wait and see what happens. . . .

 

Why is evolution theory so mealy-mouthed, so reliant on metaphors? Why can't it just say what it means, literally?

 

Because it is complex and you aren't going to get a comprehensive description from the short label you use for a process. Why would you expect to?

[CharonY]

Speciation event is really speciation "event." Sort of an event, but not really. More like an ongoing process. (The literal event occurs when the taxonomists say it does.)

Natural selection is really natural "selection." Sort of like selection, but not really. More like wait and see what happens (i.e., see how distribution of reproductive success yields trait distributions among offspring)

Selection pressure is really selection "pressure." Sort of like pressure, but not really. More like wait and see what happens. . . .

 

Why is evolution theory so mealy-mouthed, so reliant on metaphors? Why can't it just say what it means, literally?

 

And that is simply because you lack knowledge to understand the context and meaning of these words. That is a general language thing. If I say, I drive to work, you are likely to assume that I am on motorized vehicle and not a horse. This is due to the fact that motorized vehicles are more common, and you know that. But any advanced topic will have specific language use or jargon and one has to learn context in order to understand it. Go to any mechanical workshop and see what they shout at each other (unless you happen to be familiar with all the tools and terms).

Speciation event is probably one of those - misunderstood - expressions that causes novices to think it is a step-change in evolution. A bit like 'Big Bang' causes people to think of the inflationary epoch as an explosion in space.

 

What do you call the evolutionary process where a species diverges (by virtue of geographical separation) concurrently into two more as opposed to over a long time in single sequence and the old species dies off first?.Actually, knowing the names of both would be good.

 

The former is referred to as allopatric speciation. However, I am not sure whether the latter as described. In either case a separation of a part of of the population would be necessary and I am not sure how you would envision that as a single sequence. At one point or another you will have two distinct subpopulations and it does not really matter whether one gets extinct or not. Only the reconstruction would be more difficult.

In either case, if there is no geographic separation it is known as sympatric speciation.

[StringJunky]

 

And that is simply because you lack knowledge to understand the context and meaning of these words. That is a general language thing. If I say, I drive to work, you are likely to assume that I am on motorized vehicle and not a horse. This is due to the fact that motorized vehicles are more common, and you know that. But any advanced topic will have specific language use or jargon and one has to learn context in order to understand it. Go to any mechanical workshop and see what they shout at each other (unless you happen to be familiar with all the tools and terms).

 

The former is referred to as allopatric speciation. However, I am not sure whether the latter as described. In either case a separation of a part of of the population would be necessary and I am not sure how you would envision that as a single sequence. At one point or another you will have two distinct subpopulations and it does not really matter whether one gets extinct or not. Only the reconstruction would be more difficult.

In either case, if there is no geographic separation it is known as sympatric speciation.

The 'single sequence' will be the sympatric one. I knew it's not really singularly linear per se but a continuum with one species fading out, in population terms, over time. I had a job trying to describe and distinguish the two scenarios properly.

Edited February 20, 2015 by StringJunky

[CharonY]

Well, but one population being extinct is not a necessity as there is no reason why the two species would not exist side by side. The gene flow between these populations would be broken either way.

Edited February 21, 2015 by CharonY