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Pre-Historic Nookie!
#31
RE: Pre-Historic Nookie!
(August 23, 2018 at 6:51 pm)Gawdzilla Sama Wrote: Not going to happen:

[Image: Great-Dane-Chihuahua-Mix.jpg]

Male Great Dane, any gender chihuahua end up with a big dog wearing a yappy condom.

🧛‍♀️

Playing Cluedo with my mum while I was at Uni:

"You did WHAT?  With WHO?  WHERE???"
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#32
RE: Pre-Historic Nookie!
The human timeline is far less simple than we thought back in the '60s when I was learning about it. 

[Image: Human%2BEvolution%2BTaxonomy%2BChart%2B%...4%2529.jpg]
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#33
RE: Pre-Historic Nookie!
(August 23, 2018 at 11:21 pm)Minimalist Wrote: 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.

Big Grin

All dogs are dogs, yes - and the way that we express that in taxonomy is that all dogs are subspecies, or breeds.  All subspecies are categorically members of the same species.  Morphologicaly, geographically or behaviorally distinct...but not reproductively isolated from each other, and this is also our current understanding of HSS, HSN, and HSD.  Three human dogs, all dogs being dogs.  Homo is the genus, sapiens is the species...and the third is the subspecies.  

The idea that they were distinct species, ie, homo neanderthalis or homo denisova rather than homo sapiens neanderthalis and homo sapiens denisova comes from an older taxonomy that we've been revising in the same way (and for the same reason) that we used to consider wolves and dogs different species but we now know that they are not.  We used to think there was canis lupus and canis familiaris.  That's been revised to canis lupus lupus, and canis lupus familiaris.  

It was a really nice house the Neanderthals and Denisovans had, there.  Be a shame if something happened to it.  Wink
I am the Infantry. I am my country’s strength in war, her deterrent in peace. I am the heart of the fight… wherever, whenever. I carry America’s faith and honor against her enemies. I am the Queen of Battle. I am what my country expects me to be, the best trained Soldier in the world. In the race for victory, I am swift, determined, and courageous, armed with a fierce will to win. Never will I fail my country’s trust. Always I fight on…through the foe, to the objective, to triumph overall. If necessary, I will fight to my death. By my steadfast courage, I have won more than 200 years of freedom. I yield not to weakness, to hunger, to cowardice, to fatigue, to superior odds, For I am mentally tough, physically strong, and morally straight. I forsake not, my country, my mission, my comrades, my sacred duty. I am relentless. I am always there, now and forever. I AM THE INFANTRY! FOLLOW ME!
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#34
RE: Pre-Historic Nookie!
Here's the thing with tiny dogs and huge dogs: Even if you put them on an island and wait 10,000 years, not only will they likely be the same species at the end, they'll be the same breed. Before reproductive isolation due to incompatible size splits them off from each other, the big dogs will very likely have gotten smaller and/or the small dogs will very likely have gotten bigger, and those descendants will very likely interbreed. Without human involvement they can be expected to 'return to the mean' over generations, sans environmental pressures keeping them from varying in size (maybe a prey animal only tiny dogs can get at coupled with a food source only big dogs can reach with a dearth of food sources for medium dogs, for example). On the other hand, they will probably be a subspecies or even a different species from all the other dogs in the world, because of their reproductive isolation from dogs outside the island.
I'm not anti-Christian. I'm anti-stupid.
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#35
RE: Pre-Historic Nookie!
(August 24, 2018 at 9:56 am)Mister Agenda Wrote: Here's the thing with tiny dogs and huge dogs: Even if you put them on an island and wait 10,000 years, not only will they likely be the same species at the end, they'll be the same breed. Before reproductive isolation due to incompatible size splits them off from each other, the big dogs will very likely have gotten smaller and/or the small dogs will very likely have gotten bigger, and those descendants will very likely interbreed. Without human involvement they can be expected to 'return to the mean' over generations, sans environmental pressures keeping them from varying in size (maybe a prey animal only tiny dogs can get at coupled with a food source only big dogs can reach with a dearth of food sources for medium dogs, for example). On the other hand, they will probably be a subspecies or even a different species from all the other dogs in the world, because of their reproductive isolation from dogs outside the island.

Assuming the big dogs don’t eat the small dogs before they converge on a common optimally island adopted breed. It seems the chances are that insular dwarfism will make the unified breed emerging after 10000 years much smaller than the common ancesters of the big and small breeds that are initially placed on the island.
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#36
RE: Pre-Historic Nookie!
The probability that a successful gestation will occur with animals this disproportionate has been deemed "unlikely". Sorry I didn't bookmark that study.
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#37
RE: Pre-Historic Nookie!
That’s why there is artificial insemination and dog C-section.
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#38
RE: Pre-Historic Nookie!
(August 24, 2018 at 10:43 am)Anomalocaris Wrote: That’s why there is artificial insemination and dog C-section.

Non-viable embryos.
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#39
RE: Pre-Historic Nookie!
Danny Vendramini authored Them and Us: How Neanderthal Predation Created Modern Humans 

This is a pretty good read.  He has a very different take on the relationship between neanderthals and humans.  Basically They (HSN) hunted US (HSS) into a genetic bottleneck approximately 40,000 years ago taking place in the western middle east called the Lavant (modern day Sirya, Jordan, Isral, Lebanon).  What came out of that bottle neck was in effect modern humans.  

Traits like relative hairlessness, erect posture (to the detriment of our spine), and our walking gate became more exaggerated because they gave our HSS ancestors long distance visual clues to better evade potential fatal interactions with groups or even individual HSN.  

Violent conflict between HSS and HSN further refined the HSS genetic pool leading to the bottleneck.  Groups of HSS who had superior communication skills, superior intellect, and were also physically tough and aggressive tended to survive interactions with HSN better than those who were not.  

Sexual traits like permanent female sexual dimorphism but with out clear signs of estrus (HSS are the only great ape where females have no obvious outward sign of estrus), helped to cut down on HSN rapes of HSS.

Vendramini goes on to state that the HSS that came out of the genic bottle neck turned tables on the HSN and began to hunt them down, effectively wiping HSN out in around 10,000 years.  Early groups of HSS also were so aggressive that they also wiped out any other more archaic HS species they happen upon, leading to the genetic similarity of modern humans.



I personally think that Vendramini has an unaddressed problem with the theory.  If he is correct than HSN-HSS crossbreeding had to have taken place after the genetic bottle neck, when HSS groups had splintered, and some of them had entered the African continent.  It makes sense that modern European HSS have more HSN dna (proximity) but according to Vendramini's theory modern African populations should have at least some trace amounts of HSN DNA.  I guess it is possible that the HSN dna in African populations became so dilute it cannot be measured, but i don't think it works like that.
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#40
RE: Pre-Historic Nookie!
The prevailing idea about the genetic bottleneck puts it on the Toba supervolcano erupting some 70,000 years ago which allegedly slaughtered the HSS community and reduced it to a relative handful of individuals living in East Afrcia and from whom all modern human are descended.

The obvious problem with the idea is that for a volcanic eruption it seems highly specialized.  The Neanderthals don't seem to know that they were all killed.  Worse, the megafauna, which did die off in North America some 60,000 years later from unknown causes, seems to have come through Toba unscathed.  Now I am perfectly willing to accept that a monumental volcanic blast and subsequent "nuclear winter" scenario would significantly impact life.  But no one would be getting an exemption from it.  The effects would be world-wide as we have seen with much smaller volcanic events which triggered the Little Ice Age for example.

We see similar arguments from some of the creatards we have around here who insist their fucking flood story is real but then can't explain how the Egyptians kept building pyramids even though they had just been drowned.  No.
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