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Dinosaur tail discovered trapped in amber (2016)
- powmedia 9y agoLife will find a way
- HankB99 9y agoI wonder if we can get some DNA from it.
- notlob 9y ago> I wonder if we can get some DNA from it. From the article: “McKellar said that soft tissue and decayed blood from the tail were found in the amber but no genetic material was preserved.”
- delecti 9y agoThe half life of DNA is roughly 521 years [1]. The sample was 99 million years old, so you could expect roughly 3.33347 × 10^-57200 [2] percent of the DNA to be left. And considering humans have about 7 billion base pairs [3], you could reasonably expect no real recoverable information to remain. [1] http://rspb.royalsocietypublishing.org/content/early/2012/10/05/rspb.2012.1745 http://rspb.royalsocietypublishing.org/content/early/2012/10... [2] https://www.wolframalpha.com/input/?i=0.5%5E(99+million+%2F+521) https://www.wolframalpha.com/input/?i=0.5%5E(99+million+%2F+... [3] https://en.wikipedia.org/wiki/Human_genome https://en.wikipedia.org/wiki/Human_genome
- throwaway613834 9y agoIn what sense does DNA have a half-life? It can't be radioactivity so is it seems to be just about molecular disintegration? Which is weird because why should a stable structure have a half-life?
- anamexis 9y agoThe introduction of the first citation explains it a little bit: > DNA has limited chemical stability and decays without the enzymatic repair mechanisms of living cells [18]. Following cell death, nucleases start to cleave the DNA into fragments [19] and during decomposition, the DNA is digested by micro-organisms [18,20]. In determining long-term DNA decay, it is believed that hydrolysis of amino groups accelerates the loss of purine residues (depurination), resulting in strand cleavage [21,22]. This random DNA fragmentation generates a characteristic negative exponential correlation between DNA fragment length and number of molecules (figure 1a) [23,24,26,27].
- throwaway613834 9y agoThanks! I even clicked on the link and read every sentence that had "half" in it but didn't see anything... didn't expect it to be somewhere else in the introduction haha.
- delecti 9y agoAs a general rule, it's safe to assume every word in the abstract of a paper is significant.
- throwaway613834 9y ago> As a general rule, it's safe to assume every word in the abstract of a paper is significant. ...what? The sentence quote above was from the introduction, not the abstract. Nothing in the abstract answered my question of why a stable structure like that of DNA should undergo disintegration. (Did you read the abstract yourself?)
- garmaine 9y agoTo be fair, many of those processes are things that I would presume halt at some point in an isolated chemical environment. Also, what kind of breakdown? If segments up to a certain sizer were stable, that would be enough to reconstruct a full genome of the sequencers were sensitive enough and the final segments long enough.
- BurningFrog 9y agoEven so... the broken fragments would lie next to each other, and with some future technology it's not unthinkable that they could be reconstructed. Or is there something fundamental I'm not aware of?
- yjftsjthsd-h 9y agoIt really depends; entropy is a harsh mistress. The output of a paper shredder can theoretically be reformed into the source paper, but below a certain size fragment there's not enough information left to recover.
- anilakar 9y agoIf that's the case, you better start learning to use those UNIX systems soon.
- lifeisstillgood 9y agoit's quite beautiful ... and feathered, definitely feathered :-)
- seandougall 9y agoFascinating! (Also [2016])
- Yuioup 9y agoArticle is from 2016
- deleted 9y ago[deleted]
- em3rgent0rdr 9y ago"the specimen, the size of a dried apricot..."
- em3rgent0rdr 9y agoDon't know why I was downvoted...it is a common pastime on HN to laugh at these types of comparisons.
- BugsJustFindMe 9y agoI didn't do it, but I'm going to guess that it was because your comment gave absolutely no context or meaningful input, and it therefore seems reasonable that someone has decided that it adds no value to discussion of the article. I did downvote this one though, because of the antepenultimate entry in https://news.ycombinator.com/newsguidelines.html https://news.ycombinator.com/newsguidelines.html
- curtis 9y agoThe most interesting part to me is that there are feathers trapped inside the amber: > The amber, which weighs 6.5 grams, contains bone fragments and feathers, adding to mounting fossil evidence that many dinosaurs sported primitive plumage...
- glauque 9y agoIndeed, and a fairly recent discovery among Velociraptors. > The feathers of the flightless Velociraptor may have been used for display, for covering their nests while brooding, or for added speed and thrust when running up inclined slopes. https://en.wikipedia.org/wiki/Velociraptor#Feathers https://en.wikipedia.org/wiki/Velociraptor#Feathers http://science.sciencemag.org/content/317/5845/1721 http://science.sciencemag.org/content/317/5845/1721
- DrScump 9y agoThe paper: http://www.cell.com/current-biology/fulltext/S0960-9822(16)31193-9 http://www.cell.com/current-biology/fulltext/S0960-9822(16)3... "A Feathered Dinosaur Tail with Primitive Plumage Trapped in Mid-Cretaceous Amber"
- m3kw9 9y agoI would go back to the market, pay the man extra and ask him to help trace where it came from, as there could be more where it came from
- couchand 9y agoWell, the article has a photo of the field where it came from, so presumably something more or less like that has already happened...
- lostlogin 9y agoThe mining photo looks really grim, and reminds me of the mammoth tusk mining photos that were linked to from HN a few weeks back. https://www.google.co.nz/amp/photofunonline.com/photographer-joins-illegal-mammoth-tusk-hunt-in-siberia-captures-how-they-get-rich-get-drunk-and-nearly-die/amp/ https://www.google.co.nz/amp/photofunonline.com/photographer...
- Frogolocalypse 9y agoClearly there are feathers. Is it finally settled then? Land-based dinosaurs probably all, or at least most, had feathers?
- moultano 9y agoThe assumption right now is that every theropod had feathers of some kind somewhere. Some of them may have lost them as adults, or only be partially covered, the skin impression information is somewhat inconsistent. But generally yes, theropods looked very much like big carnivorous flightless birds, plumage and all. Velociraptor for instance likely had what today we would describe as wings.
- krylon 9y agoJurassic Park lied to me! Even though the link between dinosaurs and birds is mentioned explicitly. :( Would be interesting to see a remake that used all of the current knowledge about dinosaurs, what they looked and behaved like.
- bringtheaction 9y agoThe most recent Jurassic Park movie has a solution to this problem. In it they say that they had to use genes from amphibians together with the dinosaur genes in order to create their animals. This way the issue is reconciled.
- krylon 9y agoNow that I think of it, they mentioned the amphibian DNA in the first one (and the book), too, to explain why the dinosaurs were suddenly able to procreate. Still, a life-size velociraptor ot T-Rex covered in a coat of feathers must be quite a sight.
- malydok 9y agoI wonder how much the CGI production costs would rise :-)