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Equus (History)
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Mick Harper
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In: London
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This is a problem. After all, neo-Darwinism relies on random chance but that cuts both ways since it means that crocodilians must throw up mutations as often as fruit-flies. And every eco-niche by definition can be improved upon, so one would think that advantageous mutations would be roughly the same for all. Yet manifestly they aren't. Are neo-Darwinists wrestling with this theoretical problem? Or are they, as South Park insists, too busy doing it doggy-style with bisexuals to bother?
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Komorikid


In: Gold Coast, Australia
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Neo-Darwinist's greatest tool (Genetics) has now become its greatest weakness. Assumptions hitherto believed to be sacrosanct like the ONE WAY transfer of information from DNA to RNA, proteins, etc. have been overturned by modern genetics. Geneticists have found a certain enzyme that enables RNA to synthesise its own DNA. This means that a cellular mechanism for the transfer of environmental and characteristic information is possible. This reverse transcriptase is found in many different animals and is now believed to be a fundamental component of normal cells.

This new evidence shatters a core belief of neo-Darwinism which has always believed in a One Way transmission of genetic information. Lamarckism has always believed in a feedback mechanism which the new evidence confirms.
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DPCrisp


In: Bedfordshire
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Crikey! Reverse transcriptase has been known since 1970 and was the subject of the 1975 Nobel Prize. So what's been going on?

It's the method viruses use to insert virus-building DNA into host cells, so could it also be the mechanism for creating viruses in the first place?
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DPCrisp


In: Bedfordshire
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At first, I didn't catch what they were saying about horses at Longleat last weekend: "cheval-ski horses" turn out to be Przewalski's Horses. Never heard it out loud before. Just some Eastern Bloc spelling of cheval?

Apparently, yes: but only indirectly. Przewalski is the Polish version of Russian (General Nikolai) Przhevalsky, who set out to 'discover' them. And a Russian noble family called "cavalier" is no surprise.

It's true, they dunnarf look like they come straight from cave paintings and they have erect manes like zebras, but we can still be sure that a) this horse DNA mess can be cleared up by acknowledging the domestication bottleneck c. 12,000 years ago and b) you won't find clear evidence for this in the literature, only more ifs and buts, because that date is so far off the radar.
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Hatty
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In: Berkshire
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How extraordinarily romantic; Przhevalsky was a Russian geographer and explorer in the second great age of fantastical exploration, the nineteenth century, and said to have 'discovered' not only the last extant wild horse population in the central Asian wilderness but Bactrian camels and gazelles, who were also named after him.

Talking of naming, wiki says

Przhevalsky died of typhus during his fifth journey at Karakol on the shore of lake Issyk-Kul in present day Kyrgyzstan. The Tsar immediately changed the name of the town to Przhevalsk.

which goes to show how eager the Russians were to proclaim their achievements, even if he was a Polack originally. Wonder what the horses and gazelles were called by the despised natives. Presumably he'd be virtually unknown if the horse hadn't been given his name.

[He was a, no doubt undervalued, geography teacher in a military academy in Warsaw prior to his expeditions across the Asian steppes. Poles, bless 'em, consider themselves to the world's best horsemen; we were taught to ride by a Polish ex-cavalry officer, the difference between us and the rest of the British riding establishment was we rode with short stirrups].
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Mick Harper
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In: London
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We couldn't afford stirrups.
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DPCrisp


In: Bedfordshire
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You had vicious sewer rats for horses, stabled in a rolled up newspaper, and had to get up before you went to bed to curry-comb them with your tongues... eh?
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Hatty
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In: Berkshire
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That'd be newspaper wrappings culled from the fish 'n' chip place; they couldn't afford papers let alone feeding the animals.

It's true, they dunnarf look like they come straight from cave paintings and they have erect manes like zebras

They haven't been overly interbred then; breeders go for looks and docility. A friend of mine used to breed chows; he salvaged a 1920's Encyclopaedia Britannica from a skip and looked up chows, back then they looked more wolf-like, longer legs and less squashed faces. Far prettier to my mind.
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DPCrisp


In: Bedfordshire
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They haven't been overly interbred then; breeders go for looks and docility.

Yes, there's time for Przewalski's horse to have gone feral before the first horse was ever ridden... "Most like wild horses" is not the same as "the only surviving wild horses".

On Martin Clune's dog programme, they said a trait can be fixed in 7 generations. Terriers more aggressive than wolves, for instance.

And the African wild dogs are, apparently, assiduously untameable. (And pack leadership is, bizarrely, hereditary.) A failed attempt at producing a useful breed then. And when did they go feral? Any time up to 20 minutes before they were first recorded, presumably. But maybe a very long time ago. (Not all of Africa is as state-of-nature as we are accustomed to suppose.)

He was talking about genetics, so I presume the data are there to support the notion that all dogs come from wolves and that this can be roughly dated... But then, if they can get horse genetics utterly wrong...
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Hatty
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In: Berkshire
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It's one thing to modify external features but what about internal? The assertion that horses on the Peruvian altiplano are descended from the original Spanish horses is "common knowledge"; however their lungs have successfully adapted to the high altitude. Is this an example of natural evolution or interbreeding?
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Mick Harper
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Speaking of the Martin Clunes programme I couldn't quite follow his reasoning re the African Dog. Since he is so committed to the position that the domesticated dog is derived directly (via domestication) from the Wolf I was waiting to hear what he would say about the evolutionary position of the African Dog. It would be odd for two similar species to derive from a third, one by domestication and one by Darwinian means. Or alternatively it would be odder still for Animal A to evolve into Animal B which is domesticated into Animal C which is quite close to Animal A.

His main point seemed to be that the Wolf was domesticable and the African Dog wasn't. Which is an absurd position since, as far as we know, no properly wild animal is domesticable (it would seem to be a skill that the Neolithics had but we haven't). Since the African Dog is at least as close to the Domestic Dog as the Wolf is, the obvious conclusion to draw is that the Wolf is a feral Domestic Dog which was domesticated from the African Dog.

The only bar to this line of argument that he produced was that while all three animals are hierarchical, the Wolf has his leader chosen (and therefore Man can insert himself as the chosen one) whereas the African Dog always chooses the former leader's eldest son (and hence Man can't interpose himself as the new leader).

However, this is the first time I've heard of primogeniture in nature, which makes me highly suspicious (surely it would have been rung from the rafters by Royalists and such like) so we need to inspect this potentially significant matter.
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Hatty
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In: Berkshire
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Missed the programme; does the African Dog bark? It's just that wolves, while renowned for their eerie howling, don't make much noise otherwise whereas domestic mutts are particularly useful for guarding their owners and creating a rumpus. Or am I barking?
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Mick Harper
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In: London
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Here's an idea right out of left field. What if human speech originated in "horse-whispering". It would account for why Cro-Magnons were so much more developmental than hominds...they could talk. And the reason they could talk was because they had a culture based on developing simple communication commands to animals. I feel a prequel to Doctor Doolittle coming on.
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Hatty
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In: Berkshire
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What if human speech originated in "horse-whispering".


Usually if people "talk" to animals, they imitate the sounds that the animals make, rather than using human speech. Wouldn't familiarity and an understanding of animal psychology be more useful in dealing with animals than language as such?
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Mick Harper
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Perhaps you are not thinking things through far enough. Let's suppose there's this animal species whose special talent is exploiting animals. Now we know this is perfectly possible viz ants milking aphids and tons of other symbiotic examples. However, this particular animal is very large brained ie capable of a certain amount of conscious cognition (as higher primates are known to possess).

Now, as you say, one of the ways of interacting with animals is to imitate their sounds. We know this is also perfectly possible eg parrots. So this big-brained brute will surely discover that you can effect animals' behaviour by communicating with them, as it were, in their own language (since that is precisely what animals do all the time). As the B-B-B's have such a close relationship with these animals they will indeed have "a familiarity and an understanding of their animals' psychology" and will speedily observe that making the appropriate animal noise assists with their control.

It is, I would have thought, no great step to conclude that you can similarly affect your fellow big-brained brutes by imitating their sounds. Which, if you think about it, we are in a splendid position to do!
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