And, to put that into perspective, Jupiter is likely, what, several billion years old?
It's (to a close approximation) the same age as the Earth. And the most recent estimate for that which I've committed to memory is a rather convenient number : 4567 million years. No, seriously.
Since assembly of the Earth (and it's probable giant impact and the formation of the Moon from the impact debris) is modelled to have taken several millions of years, that numerical coincidence is pretty likely to have been within the duration of that assembly, to the timescale of the events themselves.
I have always wondered what would happen if an earth sized object(like one of it's many moons) crashed into Jupiter?
Ganymede, the largest, is 2634 km in radius ; Earth is 6371 km in radius. Ganymede has 0.41 of the radius of Earth and a smidgin over 7% of the volume. Since the Earth has considerable compression of it's interior due to it's size and density, the mass ratio is greater : just 2.5% (1/40th) of Earth's.
But yes, an Earth-like object (if you could find a spare one ; I'd be reluctant to use Venus, because moving it is likely to make an unholy mess for us and Mercury) would certainly make a big bang. but since it'd be about 0.3% of the mass of Jupiter, I don't think it would really do a lot of long-term harm to Jupiter. After a million years or so, you probably wouldn't be able to tell it had been there.
Could you blow the atmosphere off? No, I don't think that is remotely credible. You could create a mess in the top 50,000km or so (~4 Earth diameters) of the atmosphere, but the rest would probably not notice directly. The messed-up region would be sheared into the rest of the atmosphere on a pretty short timescale - a few thousand revolutions, a terrestrial year or so. But the internal heat engine would resume domination pretty quickly once the energy had been distributed more-or-less evenly.
Transiting an Earth-sized object through the plane of Jupiter's satellites would make a big mess though. You might strip out several of them, depending on the exact trajectory.
They discovered, in a restricted area, around 150 bones from at least 7 individuals.
Which dispenses with your last phrase as well.
I understand they can do some DNA analysis and all
A very small number of specimens have been found with collagen and traces of not-incompatible-with-dinosaur DNA. But they were in very fine-grained rocks (silt to clay grade), which tends to inhibit the drying of the material and it's access to oxygen.
From the photos in TFA (which you evidently didn't R), the sediment is reddish and contains white fragments to several centimetres in size ; I interpret that (wearing my hard hat as a professional geologist) as suggesting a well oxidised sediment (from the generally red colour) with granules of carbonate which probably grew in the soil contemporaneously with the deposition and early taphonomy of the bones as they gradually fossilised - a caliche-like deposit. That requires reasonable movement of fluids through the sediment in order to bring the carbonate together.
Both fluid movement and oxidation are bad for preservation of organic material in general, including DNA. I very much doubt that they'd get any ancient DNA out of this material. (They're not excavating in sterile garments, so modern DNA is a near certainty.)
Personally, I'd blame the BBC's science journalists for that. Using too short a timescale is something that gets my geological ire up too, and many of my colleagues.
People have been claiming that giant sauropods must have been semi-aquatic (or fully aquatic) because of their huge size for centuries, and this was the prevailing paradigm until the last 50 years or so. There's quite a lot of evidence now showing that they were at least mainly terrestrial.
Someone who doesn't use "must" when they mean "possibly,maybe,perhaps"! Excellent!
TFA describes the environment as "forest". Which is not incompatible with an elephantine lifestyle, since they live in forests - and also on savannahs, and are known to enjoy a good wallow in the mud from time to time, and to swim across rivers too.
Using the elephantine parallel, I'd anticipate that like many other animals on the planet, they had a quite broad behavioural repertoire, and since they'd have gone through quite a lot of food, they probably had to be moving frequently. Which would mean moving into differing environments regularly.
Speaking as a geologist, I keep the word "must" locked up in a drawer, the handle of which is wired to the mains to deliver an electric shock every time I touch it, and a loudspeaker booms out "Are you sure? 'MUST??' Are you really absolutely sure?" But then again, my pay cheque depends on being confident of the correctness of what I say, because back-tracking harms my client's confidence in what I say.
Otherwise it is difficult to believe it could actually walk on the earth without some help from the buoyancy provided by water.
The published accounts describe it's environment as "forest". Not "swamp". Nor "lake". Nor even "riparian" (which means river side). Since that's the opinion of a team of geologist who've been vworking this bed for some months, and would have been doing detailed sedimentology logs across the bed, microfossil analysis, grains size tracking, examination of ichnofossils associated with the remains as well as studying the regional context for kilometres around. So I suspect that what they really mean is "a forest environment . Not "swamp". Nor "lake". Nor even "riparian" (which still means river side)."
Contrary to what you may have been taught in school, people do not go around pulling these phrases out of their arses - they look for evidence of the environment, then describe it and publish it with references to the curated samples locations (museum, acquisition number), so that people who disagree can go and look at the rocks for themselves.
Since it still has a fully developed femur, it is not totally aquatic like the cetaceans. Must be similar to the hippopotami.
Elephants also have fully developed femurs and are occasionally aquatic (and also occasionally forest-dwelling,and occasionally savannah-dewlling ; in fact, they're quite flexible!). But they don't look like hippopotami. There's that "must" word in there again. Do you have some really good reason for using that word?
That may still be it's proper name, with Megalosaurus a junior synonym. There was a petition to suppress Scrotum humanum in favour of Megalosaurus bucklandii on the grounds that the former name hadn't been used in published work since 1899, but that petition was turned down. So the possibility remains for Megalosaurus to be suppressed in favour of a senior synonym.
I doubt that it'll happen though. It might cause as much of a stink as suppression of Brontosaurus.
There is however considerable grounds for thinking that a revision of Megalosaurus in general is on the cards - there are reports of bimodality in previously published material, which might indicate that the material comes from two species (or from two sexual dimorphs of one species). Someone is looking at it, but I'm not going to spend $40 to read their papers.
Jack explains how he has proven than many differently named dinosaurs are acutally the same
Horner has described a well-known problem in systematics - not just in palaeontology. Colloquially, it is known as the "lumpers versus splitters" problem (lumping multiple specimens into one "bucket" taxon versus splitting up your finds on the basis of small differences) ; it's a genuine problem throughout systematics. Unfortunately, when you've got living specimens you can go back to the field, find more, look at genes, look at biochemistry, observe changes in form and shape with development from infant to maturity... you can do a lot of things with living species. With palaeontology, you've got the bones. That's it ; end of evidence.
Horner's work on Torosaurus versus Triceratops is interesting. He makes a good case that they form a bimodal distribution of both size and form. However you can get that sort of distribution from EITHER one species that changes form with growth OR from two species which are closely related. Horner hasn't convinced the palaeontological establishment that his proposition is correct (though he has made a strong case).
When you did your early training in palaeontology, did you do the exercise of taking a bucket of cockles (Cardium sp., or whatever is convenient to your country) from the beach and trying to sort them to determine how many species there are? It's surprisingly difficult - if you haven't done it before. Which is why it would have been an exercise in one of your early palaeontology (or zoology) labs.
Give Horner a decade or two and he might win his argument - he's certainly made a good strong case to start with. Unfortunately, with just a hundred or so specimens to work from, he's not in a good position to get to a significance of 0.95, let alone 0.99. So it's going to take time and a lot more fossils to really make his case. "proven" is a big word. Horner hasn't proven his proposition.
I refer the honourable gentleman to the comments I made up-thread to the millions of fossils examined in a typical oil well (such as I drill for my living) : the numbers of microfossils we can acquire and examine is why we use these fossils instead of fossils which can exceed a millimetre in dimension.
There is no reported evidence for horns on this fossil. In fact, in the whole Sauropodomorpha, there's only moderate evidence for skull crests and the like, but no horns at all, I'm afraid (as far as I can remember ; IANA sauropod palaeontologist).
quit using synonyms for very big. it's getting tedious.
Firstly, "titan" is only a synonym for "very big" if you're ignorant of any culture other than modern American culture. There's a seam of both ancestors and descendants of the Titan pantheon to be explored if you want some different-sounding synonyms.
Secondly, the ICZN rules (you do know who the ICZN are, and what their relevance to this is, don't you? Of course you do - you raised the subject.) express a preference for Greek or Latin roots for names. Though, you do have a point in that they're much more welcoming of names based on other languages these decades, because all the Greek and Latin is getting a bit repetitive. So if you find a new, very large dinosaur completely unrelated to all other dinosaurs, then you're free to use a synonym for "very big" from Navajho, Nahuatl, or Nincompoopese.
But there you come to the "thirdly" : if re-analysis of your new fossil shows (in the opinion of other palaeontologists or zoologists, not in your opinion) that your Nuahuatal-biggie-o-saurus is actually a member of, say, the titanosaur clade, or even of a member of a previously named species or genus, then the overriding rule of nomenclature, precedence, comes into play and your new species gets re-assigned to the previously defined group. You can continue to call it whatever you want, but if other people have won the argument and call it something different, your papers may be rejected ("does not use generally accepted nomenclature"), and eventually you'll die and your folly will barely rate a line in an unpublished obituary.
The genus "Titanosaurus" was erected in 1877 to include the newly-described species Titanosaurus indicus. So good luck with preceding that. If you can do it, I would suggest that your time machine might just possibly earn you more, and longer-lasting fame then the revision of sauropod taxonomy which inspired it - in the same way that Teflon frying pans are more important than the Moon-landing programme that inspired them.
Your ignorance of the rules of taxonomic nomenclature aside (since most non-life-scientists don't have to deal with these, you're by no means alone in your ignorance), there is a valid point that the taxonomy of the Titanosauridae in particular and the Sauropodomorpha in general is a bit of a mess. That's the result, unfortunately, of a long history of incomplete and fragmentary fossils being described and published as "new species" when there's only really one (rarely two) specimens of this alleged new species. So we may well have many dubious taxa (though taxonomically valid) where the holotype material is actually just (say) a juvenile of a different species, or the other gender of another species (changes in form with age and differentiation between genders being pretty common in vertebrates in general - humans are relatively un-differentiated compared to even our closest relatives, so general experience isn't a good guide here). Unfortunately, with the quality and quantity of fossil material available, that's not a situation which is likely to improve much - largely because you can get dozens or hundreds of complete (e.g.) Compsognathus specimens from the same tonnage of preserved bone as produces one (insufficiently informative) sauropod femur.
But, if the situation really offends you, you can do something about it : learn your taxonomy ; apply yourself to the anatomy of sauropods (and other megafauna, if you want, and have time) ; do a thorough, convincing and compelling re-analysis of every sauropod fossil you can find (the first, IIRC, was reported during the Civil War. 1640 or so.) ; then work out a convincing, comprehensive and correct re-classification of the whole group. And don't publish a word of it until you've got your whole monograph ready to publish - otherwise you'll find yourself hoist on your own petard of having published on inadequate data and
I have guppy fish in a 30 gallon tank. They almost never live past 2 years in captivity. In nature however, guppies live 5 years or more.
And have you reconsidered if you should actually be keeping guppies, since it's obviously so harmful to them? Should you be continuing to replace them as they die (whether it be by purchase, or by not separating out the sexes and letting your population die out)?
Let's put that in a better known pet context. Say that you have been keeping dogs for years, and that dogs live on average to 10 years old (I've never had a dog ; this is just a guess). But you dogs mostly die before they're 4.
How long ago do you think you'd have been investigated for animal cruelty? Do you think you'd have deserved the jail time for your obvious abuse of the pets?
You could achieve that by climbing Everest in the evening. Or any of the other 8000m+ mountains, for appreciably lower risk of altitude sickness. You could even, briefly, experience weightlessness at the same time.
The shortest sea route from Eurasia to North America is considerably (some hundreds of kilometres) to the north of the Aleutian Islands, which is where the major seismic activity is.
The Bering Strait isn't "in the middle of fucking nowhere", it's the least water between two distinct and useful somewheres.
What is the "useful somewhere" on the Western side of the Bering Strait? Come to think of it, what of great use is there on the Eastern side of the Strait? Nome's last contribution to history was a diphtheria epidemic and the origin of the Iditarod race. By that point it was a failed gold rush town.
Yes, there is oil in Alaska. A long, long way away from the proposed line for this railway. And there's already a pipeline in place, which it will remain much cheaper to mainain and keep in use than to replace with tank cars on a railway. There's fair prospectivity of gas in the Chukchi sea... which will require cross-country pipelines to bring it to this route too. At which point you really do have to look at the costs of pumping directly into a LNG tanker, and sailing that to Japan as an alternative.
It's not an impossible project. It doesn't strike me as being particularly useful though.
Incidentally, someone muttered about "plate tectonics. That's obviously one of those people who don't carry maps of plate boundaries around in their head. Which I do. no problem there.
Slashdot Mirror
It's the thorium as a contaminant in the cerium oxide of the mantle.
We should be able to do that with the granite walls round here (when I'm at home ; I'm about 7000km away at work now.)
It's (to a close approximation) the same age as the Earth. And the most recent estimate for that which I've committed to memory is a rather convenient number : 4567 million years. No, seriously.
Since assembly of the Earth (and it's probable giant impact and the formation of the Moon from the impact debris) is modelled to have taken several millions of years, that numerical coincidence is pretty likely to have been within the duration of that assembly, to the timescale of the events themselves.
Pierson's Puppeteer anyone? Do you want one to be your bar tender? After you realise that they prepare your drink with their mouth?
That, I would hope to see change as producers and artists explore the capabilities of CGI. Particularly "live action" CGI.
Ganymede, the largest, is 2634 km in radius ; Earth is 6371 km in radius. Ganymede has 0.41 of the radius of Earth and a smidgin over 7% of the volume. Since the Earth has considerable compression of it's interior due to it's size and density, the mass ratio is greater : just 2.5% (1/40th) of Earth's.
But yes, an Earth-like object (if you could find a spare one ; I'd be reluctant to use Venus, because moving it is likely to make an unholy mess for us and Mercury) would certainly make a big bang. but since it'd be about 0.3% of the mass of Jupiter, I don't think it would really do a lot of long-term harm to Jupiter. After a million years or so, you probably wouldn't be able to tell it had been there.
Could you blow the atmosphere off? No, I don't think that is remotely credible. You could create a mess in the top 50,000km or so (~4 Earth diameters) of the atmosphere, but the rest would probably not notice directly. The messed-up region would be sheared into the rest of the atmosphere on a pretty short timescale - a few thousand revolutions, a terrestrial year or so. But the internal heat engine would resume domination pretty quickly once the energy had been distributed more-or-less evenly.
Transiting an Earth-sized object through the plane of Jupiter's satellites would make a big mess though. You might strip out several of them, depending on the exact trajectory.
To the standard Slashdot-isms of RTFA and RTFS, I think we can add RTFB or WTFF too.
"Popcorn" and "enjoy" in the same sentence?
Bowfing shite. Fit for horses and ... well I'd even hesitate to feed it to an American. Unless the waterboard was broken.
He's released a series on "How to fail at tax evasion and go to jail for it", has he?
They discovered, in a restricted area, around 150 bones from at least 7 individuals.
Which dispenses with your last phrase as well.
A very small number of specimens have been found with collagen and traces of not-incompatible-with-dinosaur DNA. But they were in very fine-grained rocks (silt to clay grade), which tends to inhibit the drying of the material and it's access to oxygen.
From the photos in TFA (which you evidently didn't R), the sediment is reddish and contains white fragments to several centimetres in size ; I interpret that (wearing my hard hat as a professional geologist) as suggesting a well oxidised sediment (from the generally red colour) with granules of carbonate which probably grew in the soil contemporaneously with the deposition and early taphonomy of the bones as they gradually fossilised - a caliche-like deposit. That requires reasonable movement of fluids through the sediment in order to bring the carbonate together.
Both fluid movement and oxidation are bad for preservation of organic material in general, including DNA. I very much doubt that they'd get any ancient DNA out of this material. (They're not excavating in sterile garments, so modern DNA is a near certainty.)
Personally, I'd blame the BBC's science journalists for that. Using too short a timescale is something that gets my geological ire up too, and many of my colleagues.
Someone who doesn't use "must" when they mean "possibly,maybe,perhaps"! Excellent!
TFA describes the environment as "forest". Which is not incompatible with an elephantine lifestyle, since they live in forests - and also on savannahs, and are known to enjoy a good wallow in the mud from time to time, and to swim across rivers too.
Using the elephantine parallel, I'd anticipate that like many other animals on the planet, they had a quite broad behavioural repertoire, and since they'd have gone through quite a lot of food, they probably had to be moving frequently. Which would mean moving into differing environments regularly.
Speaking as a geologist, I keep the word "must" locked up in a drawer, the handle of which is wired to the mains to deliver an electric shock every time I touch it, and a loudspeaker booms out "Are you sure? 'MUST??' Are you really absolutely sure?" But then again, my pay cheque depends on being confident of the correctness of what I say, because back-tracking harms my client's confidence in what I say.
The published accounts describe it's environment as "forest". Not "swamp". Nor "lake". Nor even "riparian" (which means river side). Since that's the opinion of a team of geologist who've been vworking this bed for some months, and would have been doing detailed sedimentology logs across the bed, microfossil analysis, grains size tracking, examination of ichnofossils associated with the remains as well as studying the regional context for kilometres around. So I suspect that what they really mean is "a forest environment . Not "swamp". Nor "lake". Nor even "riparian" (which still means river side)."
Contrary to what you may have been taught in school, people do not go around pulling these phrases out of their arses - they look for evidence of the environment, then describe it and publish it with references to the curated samples locations (museum, acquisition number), so that people who disagree can go and look at the rocks for themselves.
Elephants also have fully developed femurs and are occasionally aquatic (and also occasionally forest-dwelling ,and occasionally savannah-dewlling ; in fact, they're quite flexible!). But they don't look like hippopotami. There's that "must" word in there again. Do you have some really good reason for using that word?
I think that you've been figuratively breathing too much vacuum recently.
It's as heavy as a very light truck carrying 13 African international standard elephants.
Correct - good Christians don't exist.
I doubt that it'll happen though. It might cause as much of a stink as suppression of Brontosaurus.
There is however considerable grounds for thinking that a revision of Megalosaurus in general is on the cards - there are reports of bimodality in previously published material, which might indicate that the material comes from two species (or from two sexual dimorphs of one species). Someone is looking at it, but I'm not going to spend $40 to read their papers.
Horner has described a well-known problem in systematics - not just in palaeontology. Colloquially, it is known as the "lumpers versus splitters" problem (lumping multiple specimens into one "bucket" taxon versus splitting up your finds on the basis of small differences) ; it's a genuine problem throughout systematics. Unfortunately, when you've got living specimens you can go back to the field, find more, look at genes, look at biochemistry, observe changes in form and shape with development from infant to maturity ... you can do a lot of things with living species. With palaeontology, you've got the bones. That's it ; end of evidence.
Horner's work on Torosaurus versus Triceratops is interesting. He makes a good case that they form a bimodal distribution of both size and form. However you can get that sort of distribution from EITHER one species that changes form with growth OR from two species which are closely related. Horner hasn't convinced the palaeontological establishment that his proposition is correct (though he has made a strong case).
When you did your early training in palaeontology, did you do the exercise of taking a bucket of cockles (Cardium sp., or whatever is convenient to your country) from the beach and trying to sort them to determine how many species there are? It's surprisingly difficult - if you haven't done it before. Which is why it would have been an exercise in one of your early palaeontology (or zoology) labs.
Give Horner a decade or two and he might win his argument - he's certainly made a good strong case to start with. Unfortunately, with just a hundred or so specimens to work from, he's not in a good position to get to a significance of 0.95, let alone 0.99. So it's going to take time and a lot more fossils to really make his case. "proven" is a big word. Horner hasn't proven his proposition.
I refer the honourable gentleman to the comments I made up-thread to the millions of fossils examined in a typical oil well (such as I drill for my living) : the numbers of microfossils we can acquire and examine is why we use these fossils instead of fossils which can exceed a millimetre in dimension.
There is no reported evidence for horns on this fossil. In fact, in the whole Sauropodomorpha, there's only moderate evidence for skull crests and the like, but no horns at all, I'm afraid (as far as I can remember ; IANA sauropod palaeontologist).
Do you think people just make this stuff up?
Firstly, "titan" is only a synonym for "very big" if you're ignorant of any culture other than modern American culture. There's a seam of both ancestors and descendants of the Titan pantheon to be explored if you want some different-sounding synonyms.
Secondly, the ICZN rules (you do know who the ICZN are, and what their relevance to this is, don't you? Of course you do - you raised the subject.) express a preference for Greek or Latin roots for names. Though, you do have a point in that they're much more welcoming of names based on other languages these decades, because all the Greek and Latin is getting a bit repetitive. So if you find a new, very large dinosaur completely unrelated to all other dinosaurs, then you're free to use a synonym for "very big" from Navajho, Nahuatl, or Nincompoopese.
But there you come to the "thirdly" : if re-analysis of your new fossil shows (in the opinion of other palaeontologists or zoologists, not in your opinion) that your Nuahuatal-biggie-o-saurus is actually a member of, say, the titanosaur clade, or even of a member of a previously named species or genus, then the overriding rule of nomenclature, precedence, comes into play and your new species gets re-assigned to the previously defined group. You can continue to call it whatever you want, but if other people have won the argument and call it something different, your papers may be rejected ("does not use generally accepted nomenclature"), and eventually you'll die and your folly will barely rate a line in an unpublished obituary.
The genus "Titanosaurus" was erected in 1877 to include the newly-described species Titanosaurus indicus. So good luck with preceding that. If you can do it, I would suggest that your time machine might just possibly earn you more, and longer-lasting fame then the revision of sauropod taxonomy which inspired it - in the same way that Teflon frying pans are more important than the Moon-landing programme that inspired them.
Your ignorance of the rules of taxonomic nomenclature aside (since most non-life-scientists don't have to deal with these, you're by no means alone in your ignorance), there is a valid point that the taxonomy of the Titanosauridae in particular and the Sauropodomorpha in general is a bit of a mess. That's the result, unfortunately, of a long history of incomplete and fragmentary fossils being described and published as "new species" when there's only really one (rarely two) specimens of this alleged new species. So we may well have many dubious taxa (though taxonomically valid) where the holotype material is actually just (say) a juvenile of a different species, or the other gender of another species (changes in form with age and differentiation between genders being pretty common in vertebrates in general - humans are relatively un-differentiated compared to even our closest relatives, so general experience isn't a good guide here). Unfortunately, with the quality and quantity of fossil material available, that's not a situation which is likely to improve much - largely because you can get dozens or hundreds of complete (e.g.) Compsognathus specimens from the same tonnage of preserved bone as produces one (insufficiently informative) sauropod femur.
But, if the situation really offends you, you can do something about it : learn your taxonomy ; apply yourself to the anatomy of sauropods (and other megafauna, if you want, and have time) ; do a thorough, convincing and compelling re-analysis of every sauropod fossil you can find (the first, IIRC, was reported during the Civil War. 1640 or so.) ; then work out a convincing, comprehensive and correct re-classification of the whole group. And don't publish a word of it until you've got your whole monograph ready to publish - otherwise you'll find yourself hoist on your own petard of having published on inadequate data and
And have you reconsidered if you should actually be keeping guppies, since it's obviously so harmful to them? Should you be continuing to replace them as they die (whether it be by purchase, or by not separating out the sexes and letting your population die out)?
Let's put that in a better known pet context. Say that you have been keeping dogs for years, and that dogs live on average to 10 years old (I've never had a dog ; this is just a guess). But you dogs mostly die before they're 4.
How long ago do you think you'd have been investigated for animal cruelty? Do you think you'd have deserved the jail time for your obvious abuse of the pets?
Not so comfortable thinking that way, is it?
John Herbert, of Spooner Street, Quahog
Don't forget the phosphate - the end of which element's cheap supply is looming on the horizon.
You could achieve that by climbing Everest in the evening. Or any of the other 8000m+ mountains, for appreciably lower risk of altitude sickness. You could even, briefly, experience weightlessness at the same time.
Just because lots of people do it doesn't mean that it's a sensible thing to do.
See, for example, http://www.iris.edu/seismon/zo...
What is the "useful somewhere" on the Western side of the Bering Strait? Come to think of it, what of great use is there on the Eastern side of the Strait? Nome's last contribution to history was a diphtheria epidemic and the origin of the Iditarod race. By that point it was a failed gold rush town.
Yes, there is oil in Alaska. A long, long way away from the proposed line for this railway. And there's already a pipeline in place, which it will remain much cheaper to mainain and keep in use than to replace with tank cars on a railway. There's fair prospectivity of gas in the Chukchi sea ... which will require cross-country pipelines to bring it to this route too. At which point you really do have to look at the costs of pumping directly into a LNG tanker, and sailing that to Japan as an alternative.
It's not an impossible project. It doesn't strike me as being particularly useful though.
Incidentally, someone muttered about "plate tectonics. That's obviously one of those people who don't carry maps of plate boundaries around in their head. Which I do. no problem there.