Horses in middle earth

Thats it, go on, blame me !  
But, on the bright side, thanks to me we have new & interesting issues  

"genomic signatures of population size"??

If you have a sample of genomes from a particular time I guess you might get that from variability, but how can a single genome show variability through time? WTF?

David wrote:What you called "actions" are called gaits in English.

i meant as in "he's in action" like.. a .. nevermind.

david wrote:Yes, the Icelandic horses are beautiful, intelligent and kind. My neighbor a few miles away has two of them. I think if I tried to ride one my toes would drag though. They must have had tiny vikings in Iceland!

aw, but they're perfect for me ^^ also they're very strong.

i think in tølt two and two feet touch the ground but i can't explain it. you'll just have to google or watch the vid  

halfwise wrote:"genomic signatures of population size"??

If you have a sample of genomes from a particular time I guess you might get that from variability, but how can a single genome show variability through time?  WTF?  

i am guessing that the genome is a gene and the gene only transfers from mother to daughter and it can tell how old a breed is and date it and probably population as well.

halfwise wrote:"genomic signatures of population size"??

If you have a sample of genomes from a particular time I guess you might get that from variability, but how can a single genome show variability through time?  WTF?  

This is way out of my area, but I know that there's a lot that can be inferred from the statistical analysis of a complete genome.  
The abstract of the original paper in "Nature" is here: http://www.nature.com/nature/journal/v499/n7456/full/nature12323.html

Recalibrating Equus evolution using the genome sequence of an early Middle Pleistocene horse
   Ludovic Orlando

Editor's summary

A low-coverage draft genome sequence has been obtained from a horse bone recovered from a permafrost site in the Yukon Territory, Canada, dated to around 560,000–780,000 years before present. This is by far the earliest genome sequence so far determined. The data were compared to draft genome sequences for a Late Pleistocene horse, those of five contemporary domestic horse breeds, a Przewalski's horse and a donkey. Comparative genomics suggest that the Equus lineage that gave rise to all contemporary horses, zebras and donkeys originated about 4.0–4.5 million years ago — much earlier than previously suspected. The data support the contention that Przewalski's horses — an endangered subspecies native to the Mongolian steppes — represent the last surviving wild horse population.

Norc wrote:

david wrote:
i think in tølt two and two feet touch the ground but i can't explain it. you'll just have to google or watch the vid  

The pictures help some, but you're right. I'll need to see it in motion when I get wifi.

ah yeah, but do you have at least an inkling of how a single genome can carry population history in it? maybe something in the junk DNA that piles up over time? (though it has been found that much of the DNA formerly considered junk actually is expressed in different situations. A very rich field I don't know much about.)

I'm as much in the dark as you are, which is why this stuff is fascinating!

I'm guessing the technique is similar in principle to creating an image from electron scatter in an electron microscope, or looking through walls with IR imaging. In this case they took 7 modern descendant genomes for a base line, and two ancient ones for focus.

Within that context you could then compare strings of "junk DNA" that are known to vary at a statistically consistent rate within a closed population, and the rate of variation should then give you some idea of the size of the gene pool.
That's just a wild guess though.
Probably I should go to the library and actually read the article.

aw. cutie  a young shadowfax?

btw, what colour was shadowfax?

btw, what colour was shadowfax?- Norc

Cute horse, must be young or that fall would've broken something.

David H wrote:I'm as much in the dark as you are, which is why this stuff is fascinating!

I'm guessing the technique is similar in principle to creating an image from electron scatter in an electron microscope, or looking through walls with IR imaging.  In this case they took 7 modern descendant genomes for a base line, and two ancient ones for focus.  

Within that context you could then compare strings of "junk DNA" that are known to vary at a statistically consistent rate within a closed population, and the rate of variation should then give you some idea of the size of the gene pool.  
That's just a wild guess though.  
Probably I should go to the library and actually read the article.

That would only work if you have a monotonic population growth, whereas the abstract says the population size fluctuated several times. Yeah, worth digging up that paper if only to figure out how they got that.

There's a sentence in my book that says Shadowfax was grey ?

Shadowfax is White or silver white cangiante effect

azriel wrote:There's a sentence in my book that says Shadowfax was grey?

Quite correct Azriel. Shadowfax is described as grey, and even 'shadow-grey' [mane and coat] in Tolkien's text 'Nomenclature'. Sometimes he shines 'like silver' too in certain descriptions.

Tolkien couldn't use pictures obviously, so he chose words [again obviously], and he chooses the word 'white' for some horses [Snowmane, Asfaloth], and 'grey' for others, like Shadowfax.

That much is not in debate. I think

Poop, your right Mrs figg, Shadowfax is said to be silver by day & a little darker by night, I got it wrong, mistaking silver for grey !
Take it back, (after Elthir bigged me up !   )

But you were not wrong Azriel, see my last post

Sometimes he shines 'like silver' too in certain descriptions. - Elthir

I am curious Elthir- are they all descriptions in moonlight?

Just wondering if Shadowfax's coat colour is partly reflective of the ambient light falling on it.
So in broad sunlight the coat is white, overcast days grey and silver by moon or star light?

That makes sense !

Pettytyrant101 wrote: (...) I am curious Elthir- are they all descriptions in moonlight?

Just from memory, I do not think so Petty [on the like silver/moonlight issue]. I can gather them up and get the larger context concerning any light, if I refer to my 'horse colour description' post...

... somewhere in this forum.

Well, what you waiting on?! Lore Masters, so lazy!  

LOL. Hmm, I'm not really sure if my old post will refer me to the pages needed.

I must find the descriptions in the books probably, but right now I'm pretty sure [!] one reference to silver is a bit after Gandalf the White reveals himself to Aragorn, Legolas and Gimli [and he calls Shadowfax if I remember correctly]-- and for example, maybe another 'silver' reference when Gandalf is seen riding out of Minas Tirith.

That would be two anyway.

Edited. Even though it says so below too.

halfwise wrote:
That would only work if you have a monotonic population growth, whereas the abstract says the population size fluctuated several times.  Yeah, worth digging up that paper if only to figure out how they got that.

The title of the article, Recalibrating Equus evolution using the genome sequence of an early Middle Pleistocene horse, seems to imply that there's an existing evolutionary model that's being recalibrated, as opposed to creating a new model from the 9 individuals listed, so presumably there's a pile of genetic and paleontological data we're not aware of. I wish we could download that Nature article without paying and see what's really going on..... 

Elthir wrote:Sometimes he shines 'like silver' too in certain descriptions.

Just out of curiosity, what colour would you say silver is?



{{{It looks grey to me.. }}}

Edited. Removed edits