Implausable hybrids

[Strange]

Talking of species, as we were in another thread, the idea that two species cannot inter-breed or hybridise is shown to be false in many examples.

Here is an amazing example of a hybrid of two different species that are also from two different genera, and even different families:

https://www.quantamagazine.org/extra-dna-may-make-unlikely-hybrid-fish-possible-20200805/

Quote

“It’s like if they had a cow and a giraffe make a baby.” Then he quickly corrected himself, because the lineages of those two ruminants split only a few dozen million years ago. The evolutionary paths of paddlefish and sturgeons diverged 184 million years ago. 

 

[joigus]

On a related note, but much more humbling for us:

https://www.newscientist.com/article/dn11330-pubic-lice-leapt-from-gorillas-to-early-humans/#:~:text=A genetic analysis of pubic,about 3.3 million years ago.&text=But they claim it is,from having sex with gorillas.

I don't want to draw any conclusions. Just saying...

The most interesting thing is whether these hybrids of sturgeon and paddlefish can in turn reproduce. Most admixing results into sterile individuals.

[MANDREWS85]

https://en.wikipedia.org/wiki/Mule

 

 

https://en.wikipedia.org/wiki/Hinny

Edited August 14, 2020 by MANDREWS85
hinny

[joigus]

22 hours ago, MANDREWS85 said:

https://en.wikipedia.org/wiki/Mule

 

 

https://en.wikipedia.org/wiki/Hinny

Those are quite plausible. I applaud them.  

[Strange]

5 minutes ago, joigus said:

Those are quite plausible. I applaud them.

Oh, very good. 👏

[MANDREWS85]

On 8/15/2020 at 11:20 AM, joigus said:

Those are quite plausible. I applaud them.  

I didn't know hinny's were a thing. I learned something.

[joigus]

1 minute ago, MANDREWS85 said:

I didn't know hinny's were a thing. I learned something.

Everything is a thing.

Sorry. Jokes aside. I mean, those are not very implausible hybrids, are they? Horses and donkeys diverged, what, tens of thousands of years ago?

[hu??]

I wonder if this can be explained by the species not sharing a habitat: then there is no evolutionary pressure for genetic incompatibility as a species advantage.

The generic compatibility is then only very unlikely.

Edited August 18, 2020 by hu??

[joigus]

26 minutes ago, hu?? said:

I wonder if this can be explained by the species not sharing a habitat: then there is no evolutionary pressure for genetic incompatibility as a species advantage.

The generic compatibility is then only very unlikely.

Part of it is geographic isolation, there are also environmental pressures conditioned by different circumstances in the different "cells of isolation", but there's a very important factor which is genetic drift:

https://en.wikipedia.org/wiki/Genetic_drift

 

Edited August 18, 2020 by joigus

[CharonY]

1 hour ago, hu?? said:

I wonder if this can be explained by the species not sharing a habitat: then there is no evolutionary pressure for genetic incompatibility as a species advantage.

The generic compatibility is then only very unlikely.

Generally speaking there is no selective pressure to maintain incompatibility. Quite the reverse, actually. Factors that introduce incompatibility (i.e. increase infertility in certain pairings) are more likely selected against, as the potential mating pool decreases. If in the same habitat, there is more likely of intermixing and maintenance of some level of compatibility is a likely scenario. Once separated, the genetic pools can drift further apart.

[MANDREWS85]

On 8/17/2020 at 5:49 PM, joigus said:

Everything is a thing.

Sorry. Jokes aside. I mean, those are not very implausible hybrids, are they? Horses and donkeys diverged, what, tens of thousands of years ago?

I was going with the giraffe and cow quote from the OP.  Seam's like giraffes and cows aren't so much different then horses and donkeys?  I'm no expert in the field.  Just thought that was interesting.

[MANDREWS85]

Elaborate if we are going by Taxonomic rank or not(had to remind my self lol)?

 

[/img]

 

[Strange]

9 hours ago, MANDREWS85 said:

I was going with the giraffe and cow quote from the OP.  Seam's like giraffes and cows aren't so much different then horses and donkeys?  I'm no expert in the field.  Just thought that was interesting.

Horses and donkeys belong to the same genus (Equus). There are quite a few hybrids possible between horse-like species.

Giraffes and cows are from different families (they are both in the order artiodactyla). Taxonomically, this is the same as the two species of fish, but in terms of time, the fish diverged much longer ago.

(Even if giraffes and cows were almost genetically identical, for purely physical reasons they would not be able to interbreed and so would probably be considered separate species or sub-species)

[hu??]

22 hours ago, joigus said:

Part of it is geographic isolation, there are also environmental pressures conditioned by different circumstances in the different "cells of isolation", but there's a very important factor which is genetic drift:

https://en.wikipedia.org/wiki/Genetic_drift

 

I know. Those are known factors but are not the whole story. Different species can also evolve in the same habitat.

E.g. i can imagine that adaption A gives an advantage and adaption B give a different advantage, but the mix gives a disadvantage relative to A or B separate. Genetic incompatibility is than also an advantage. Perhaps not for the individual but for the new species it is.

[joigus]

1 hour ago, hu?? said:

I know. Those are known factors but are not the whole story. Different species can also evolve in the same habitat.

E.g. i can imagine that adaption A gives an advantage and adaption B give a different advantage, but the mix gives a disadvantage relative to A or B separate. Genetic incompatibility is than also an advantage. Perhaps not for the individual but for the new species it is.

That sounds to me like sympatric speciation. In plants it's common, but in animals it seems to be not so common and to have more to do with sexual conflict than with adaptation. Allopatric speciation is far more likely.

But I'm sure even that is not the whole story. In species like humans, which are very successful across different environments, and have been for several hundreds of thousands of years, hybridization has very likely played an important part. But this drifts us apart from the topic.

[MANDREWS85]

11 hours ago, Strange said:

(Even if giraffes and cows were almost genetically identical, for purely physical reasons they would not be able to interbreed and so would probably be considered separate species or sub-species)

I would assert that a giraffe and cow. Being sufficiently motivated, could physically get it on.

Edited August 19, 2020 by MANDREWS85

[MANDREWS85]

Not sure how far back "plausible" is, but found this interesting.  I was sitting in the library reading an old Popular Mechanics and the Denisovan's were brought to my attention.

 

[/img]

They look like Hobbits or Gelflings.

https://en.wikipedia.org/wiki/Denisovan

The Denisovans or Denisova hominins ( /dɪˈniːsəvə/ di-NEE-sə-və) are an extinct species or subspecies of archaic human that ranged across Asia during the Lower and Middle Paleolithic (potentially surviving as late as 30,000–14,500 years ago in New Guinea). Denisovans are known from few remains, and, consequently, most of what is known about them comes from DNA evidence. Pending consensus on their taxonomic status, they have been referred to as Homo denisova, H. altaiensis, or H. sapiens denisova.

The first Denisovan individual was identified in 2010 based on mitochondrial DNA (mtDNA) extracted from a juvenile female finger bone from the Siberian Denisova Cave. Nuclear DNA (nDNA) indicates close affinities with Neanderthals. The cave was also periodically inhabited by Neanderthals, but it is unclear whether they ever cohabited in the cave. Additional specimens from Denisova Cave were subsequently discovered, as was a single specimen from the Baishiya Karst Cave on the Tibetan Plateau in China. This indicates they lived in a wide variety of habitats, including forests, tundras, mountains and jungles. DNA evidence suggests they had dark skin, eyes, and hair, and had a Neanderthal-like build and facial features. However, they had larger molars which are reminiscent of Middle to Late Pleistocene archaic humans and australopithecines.

Denisovans apparently interbred with modern humans, with about 3–5% of the DNA of Melanesians and Aboriginal Australians and around 6% in Papuans deriving from Denisovans. Denisovans may have interbred with modern humans in New Guinea as recently as 15,000 years ago. There is also evidence of interbreeding with the local Neanderthal population

Taxonomy

It is debated whether Denisovans represent a distinct species of Homo or are an archaic subspecies of H. sapiens. DNA analyses showing Denisovans as a sister taxon of Neanderthals also concerns the classification of the latter as H. neanderthalensis or H. s. neanderthalensis. Proposed species names for Denisovans are H. denisova^[1] or H. altaiensis.^[2]

 

 

 

 

[joigus]

Denisovans, Neanderthals and maybe other post-Heidelbergensis are a fascinating topic, but I think the original OP's intention was to make a point about possibility of implausible hybrids, more common, to say the least, in species that spawn, rather than mate the way mammals do.

Because the topic is fascinating nonetheless, I suggest splitting in a friendly and dispassionate way, or creating a new topic.