Actually, when examined over the time span when speculations occur, interbreeding between different but closely related species that resulted in some fertile offsprings is probably not rare at all.  In fact when speciation occurs in place, there is probably an extended period when inter-species breeding occurs, gradually tailingin both in frequency and in percentage resulting in fertile offsprings, as selection pressure continues to drive the species further apart genetically, until such time as their interbreeding becomes so unlikely to be fruitful in terms of permepruating their genes and therefore so likely to be a waste of energy detrimental to genetic survival, that it pays evolutionarily when behavioral or biochemical barriers against further courtship evolve.

Interspecies breeding is unbelievably rare compared to intraspecies breeding. 

If we reference a foggy moment when all three were in the act, so to speak, of speciation, we are are explicitly proposing de-facto subspecies, which is still intraspecies breeding.

(August 23, 2018 at 5:40 pm)Khemikal Wrote: Interspecies breeding is unbelievably rare compared to intraspecies breeding. 

If we reference a foggy moment when all three were in the act, so to speak, of speciation, we are are explicitly proposing de-facto subspecies, which is still intraspecies breeding.

No.  If the interbreeding between two population occurs but results in offspring sex ratio and rates of fertility dramatically from those seen with breeding within each population, then the two populations are different species.

They are not de-facto subspecies.

When one weighs whether the evidence of some success in interbreeding between Neanderthal and HSS indicates they were of the same species or of two closely related, but different species that retains limited capacity to interbreed successfully, one needs to factor in the fact that morphological differences between the populations were much larger than seen within modern HSS population, and the fact that Neanderthal appears to exhibit substantially different growth pattern from child to maturity compared to HSS.  This latter difference is not often observed within the same species.

If we see this difference in two otherwise very similar populations of bears or moose today, we are unlikely to regard them as if the same species or two subspecies under the same specie.

I give you the poodle..and the great dane. Both in the same species, as a wolf.

I feel like there's a disconnect here. I'm only relating why we ended up classifying neanderthalis as a subspecies of homo sapiens, like ourselves.

-and, yes, categorically, three populations that have not yet completed any speciation event from their parent population are subspecies. That's what a subspecies -is-. If they did complete one, they would no longer be a subspecies, they would become their own species.

(August 23, 2018 at 5:54 pm)Khemikal Wrote: I give you the poodle..and the great dane.  Both in the same species, as a wolf.  

I feel like there's a disconnect here.  I'm only relating why we ended up classifying neanderthalis as a subspecies of homo sapiens, like ourselves.

-and, yes, categorically, three populations that have not yet completed any speciation event from their parent population are subspecies.  That's what a subspecies -is-.  If they did complete one, they would no longer be a subspecies, they would become their own species.

They can each be their own species and still occasionally fruitfully interbreed.  That’s the point.  Some evidence of interbreeding is not conclusive evidence that they were of the same specie.

Many species today carry evidence of minor genetic contributions likely from other populations that are closely related but not considered its own specie. It is by no means rare or odd. The species are considered separate because they seldom or are never actually observed to interbreed and are substantially different.

Poodle and Great Dane can interbreed (sometimes with human help) and produce similar sex ratio and rate of fertility amongst the offsprings as if each breaded with another like itself.  That’s why they are considered to be of the same specie.    There is no strong evidence of that being the case between Neanderthals, Denisovans and HSS.   There seems to be some evidence genetic contribution from Neanderthals only came from one sex.  This suggest only one type of pairing (for example the female has to be Neanderthal) between HSS and Neanderthals can produce offsprings, or only offsprings of a specific sex is fertile, or there was only ever extremely few, perhaps just one, successful pairing and all of our Neanderthal genes came from that one instance and is indelibly marked by the specific circumstance of that one occurrence.

All these, if verified, would suggest Neanderthals and HSS are considerably further apart, than sub-species, with greater barrier to successful interbreeding than would normally be found in populations lumped together as variations of the same specie.

The fact that Neanderthal genes are ubiquitous amongst HSS is no proof of frequent genetic infusion. It is rather evidence that those who carry these genes enjoy significant evolutionary advantage.

Dogs evolved from wolves fine all on their own.  Then humans stepped in and fucked them up.  So much for "intelligent" design.

(August 23, 2018 at 6:22 pm)Minimalist Wrote:



Dogs evolved from wolves fine all on their own.  Then humans stepped in and fucked them up.  So much for "intelligent" design.

Ah, but it take a less unintelligent designer to design an more unintelligent one.

Not going to happen:

(August 23, 2018 at 6:17 pm)Anomalocaris Wrote: They can each be their own species and still occasionally fruitfully interbreed.  That’s the point.  Some evidence of interbreeding is not conclusive evidence that they were of the same specie.

They can be, but even saying "occasionally" is overselling it....and it's phenomenally rare compared to intraspecies breeding between subspecies.  

In this case, we see that Hss could and did breed with both Hsn and Hsd (here we are), and the find in the op shows that Hsd could breed with Hsn.  All three populations. 

Most interspecies breeding attempts lead to nothing, successful attempts most often to sterile offspring.  When I say "most"..here, I'm vastly underselling it - but leaving the possibility open.  

Between Hss, Hsn, and Hsd..they could interbreed..and their interbreeding did produce viable offspring.  Here we and the op find are.  That is pretty strong, though, granted..not entirely conclusive.

Quote:Poodle and Great Dane can interbreed (sometimes with human help) and produce similar sex ratio and rate of fertility amongst the offsprings as if each breaded with another like itself.  That’s why they are considered to be of the same specie. 

Theyre considered to be the same species because they are not reproductively isolated (but they're getting there, lol). I doubt that there was anyone breeding us - helping it along...and neither will breed with wolves - despite all three being the same species.  Poodles and great danes are both subspecies of wolf.  This one should be of particular interest to Min..as the differences between a wolf, poodle, and great dane aren't enough to imply that we need to work on the idea of species, so why would variations within a human subspecies be?  I'll say this..the taxonomy of animals has nothing on the taxonomy of plants..which goes well beyond (and under) species.


I want to be very clear.....I'm not classifying the position you're communicating to me as impossible, only stating that it's much more improbable than the subspecies explanation.

Dogs are dogs, Khem.  I have seen some strange combos on my walks through the shelters out here.... interbreeding is not a problem.

I just have a pet peeve with the idea that that HNS, HSS, Denisovans, Hobbits, etc are different species.  I think we all evolved from Homo Erectus and the superficial changes among different human groups are the result of isolation in the Darwinian sense.  Perhaps had it continued long enough separate species that were incapable of interbreeding would have been the result but we never quite got there.