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The Mini Dinosaurs from the Harz Mountains 60

Posted by samzenpus
from the still-bigger-than-a-baby's-arm dept.
FiReaNGeL writes "When unusually small dinosaur fossils were found in a quarry on the northern edge of the Harz Mountains in 1998, it was initially assumed that these were the remains of a group of young dinosaurs. This was a fallacy, as the Bonn palaeontologist, Dr. Martin Sander, recently discovered. At a maximum estimated weight of one tonne, they were only a fiftieth the weight of their closest relatives, the brachiosaurs, and thus by far the smallest of the giant dinosaurs which have ever been found."
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The Mini Dinosaurs from the Harz Mountains

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  • by crazyjeremy (857410) * on Thursday June 08, 2006 @12:51AM (#15492534) Homepage Journal
    Heh heh... he said "smallest of the giant dinosaurs"
  • Interestingly...

    This all fits in with the discovery which the scientific journal Nature reported on last year: on Flores also the 18,000-year-old bones of a 'dwarf' human. This 'Flores hobbit' was only one metre tall.

    This may fit in elegantly, but last I heard (maybe even on slashdot) this discovery was now believed to be a normal human with a disease of some sort.
    • Re:Mini-people (Score:3, Informative)

      by afaik_ianal (918433)

      This may fit in elegantly, but last I heard (maybe even on slashdot) this discovery was now believed to be a normal human with a disease of some sort.

      It's still disputed. Wikipedia has a short summary of the 2 opinions here: http://en.wikipedia.org/wiki/Homo_floresiensis#A_n ew_species.3F [wikipedia.org]

      The thing I don't understand about the hypothesis that the fossil is actually a diseased human, is that they found partial fossils of 8 other individuals, which I assume were consistent with the near-complete fossil being

      • Wait. Did you just ask what the chances were that a genetic defect would become prevalent in a tiny isolated group of individuals? After just a few generations it's near-100%. That's why inbreeding is bad. This is what created the pygmies and various other dwarf and midget populations throughout the world.

        Granted it's not nessecarily the same defect, but the idea that a small group of people is somehow immune to disease strikes me as silly.
        • That's why inbreeding is bad. This is what created the pygmies and various other dwarf and midget populations throughout the world.

          I wouldn't mind seeing a reference on a claim like that. I call BS. See http://www.discover.com/issues/may-92/features/aqu estionofsize42/ [discover.com]

          In summary, it is believed to have been a slow evolutionary process. Some of the factors they believe select a smaller size are: temperature (pygmy populations have evolved almost exclusively around the equator - being smaller makes it easi
          • I wouldn't mind seeing a reference on a claim like that. I call BS. See http://www.discover.com/issues/may-92/features/aq u [discover.com] estionofsize42/

            You should read the article you cited, where it begins to discuss the endocrinological differences between pygmies and average people, their extremely low birth size, their lack of an adolescent growth spurt, and so on. It seems your article actually supports me. Actually, essentially every reference I find which is newer than 1980 supports me. Mercedes de Onis is res
      • The thing I don't understand about the hypothesis that the fossil is actually a diseased human, is that they found partial fossils of 8 other individuals, which I assume were consistent with the near-complete fossil being debated. What are the chances of them all having this extremely rare defect, given that it shortens life expectancy, and severely limits normal brain function?

        First, as pointed out in the other reply to your post, it's not unlikely in small populations for this to occur. Second, neither

        • Second, neither shortened life expectancy nor severely limited brain function precludes survival.

          This is not the average run-of-the-mill genetic deformity. People with severe microcephaly are extremely unlikely to survive beyond childhood without care. As children, they are unable to feed. As they begin to grow, they experience seizures, fail to develop motor skills, are unable to learn, and can become paralysed. (Basically, the brain continues to try and grow as normal, but the head doesn't). I can ha
          • This is not the average run-of-the-mill genetic deformity. People with severe microcephaly are extremely unlikely to survive beyond childhood without care. As children, they are unable to feed. As they begin to grow, they experience seizures, fail to develop motor skills, are unable to learn, and can become paralysed. (Basically, the brain continues to try and grow as normal, but the head doesn't). I can handle a microcephalic child surviving to adulthood even tens of thousands of years ago. I don't buy th

    • They've since uncovered several more skeletons, all of the same stature.
    • by jd (1658) <imipak AT yahoo DOT com> on Thursday June 08, 2006 @02:11AM (#15492754) Homepage Journal
      Near the site of the "hobbits", they have found fairly advanced stone tools and stone arrowheads. People so acutely affected by the suggested dwarfing disorder would have inhibited brain function and certainly could not have developed an advanced technology or operated it. This makes it somewhere between unlikely to impossible for all of the people on the island to have been mentally afflicted. This leaves only two options - either these remains are of extremely unusual people, and were in a community of more typical hominids, and it's pure chance that no remains of these typical hominids have been found, OR they genuinely were a miniaturized subcategory of hominid that were not impaired at all, so there is no contradiction involved with there being an advanced technology.


      The debate has likely intensified even further with recent genetic studies of Neanderthals, using mtDNA extracted from the teeth. This is because the mtDNA shows vastly greater variation in early Neanderthal genetic makeup than had ever been expected. So much so that all prior studies are now considered grossly inadequate, as they only examined a hundred or so base pairs, considering the rest to be essentially identical. If genetic diversity in early hominids in general was as great as genetic diversity in early Neanderthals is believed to have been, then the probability of there having been a natural experiment in hobbits is considerably greater.


      There is, however, one outstanding problem that has NOT been resolved. Dwarfism on islands is common with reptiles. Reptiles do NOT do islands well. However, mammals on islands tend towards giantism - Amblyrhiza Inundata (a giant rat the size of a grizzly) being an excellent example. Birds, although descended from reptiles, also seem to do well on islands - the Moa (a flightless bird that was 13 feet tall) and the Haast Eagle (the largest eagle that ever lived, with a wingspan of 14 feet), both from New Zealand, being good examples. This is because mammals scale well and therefore lose very little by being large, even when resources are scarce. Reptiles don't scale so well, so there is a loss of efficiency in being large. No big deal on a large enough land mass, but on an island, it's a major problem.


      Humans, because they are potentially much better at cooperating, are capable of planning and storing, and are able to access a much wider range of foods over a much greater range of environments, should (based on knowledge of other island-based mammals) scale up on islands extremely well, and should only shrink where conflict is greatest, which would typically be a continent. It's hard to say if this is the case, as humans have always been amazingly mobile, but my gut feeling is that you'll find more very tall people on or around islands than you will in the middle of continents. This creates a problem for the hobbits, though. Mammals shrink when being able to run is a far greater survival trait than being able to gather more. On an island, there is very little to run from and almost nowhere to run to. There should, therefore, be no advantage to them being that small and therefore no reason for such a trait to be selected.


      I think it likely that the hobbits are indeed a new branch of hominids, but without a good, solid explanation for why they would be small, the theory will never be acceptable to any evolutionary scientist worth a damn, no matter how much they want it to be true, simply because it runs counter to what we know about mammals on islands. Answering that one question will probably quell a lot of the more skeptical scientists, too. A mechanism that ties things together and presents a coherent picture is more acceptable than an extrapolation, no matter how many fossils it is from.

      • by sumdumass (711423) on Thursday June 08, 2006 @03:36AM (#15492932) Journal
        How do we explain pigme people in africa? And what is to say these hobbit people originated on the island. It could be very well be that they came ot the island after fleeing from somewere else. As evolution placed the genes in pigmes, it could be the same with the hobbit people. Once it is there, it stays until watered down by outside influences just like the pigme people in africa.

        Could it be that we just don't have enough fossil or other records to even prove our current theories as fact. Sure everything points to it being this or that but what if we are missing a very large portion of the story.
        • The pygmies of Africa are relatively easy, using the conventional wisdom (ie: that mammals shrink on continents) - it's much harder to explain why there are so many taller people in Africa. Africa's a big place, with land ranging from deserts to thick jungle. Food is not a problem there, but avoiding becoming food is. The problem with a continent is that you have massive biodiversity, which means that there is a much higher likelihood of there being something capable of consuming, say, a human. Mammals have
      • by Anonymous Coward
        Also don't forget the dwarf woolly mammoths that inhabited Wrangel island until a few thousand years ago (well in to the current interglacial).

        http://en.wikipedia.org/wiki/Dwarf_mammoths [wikipedia.org]

        Clearly there are multiple factors at work that affect dwarfism or gigantism. It's not possible to predict the effects of living on an island for any particular kind of animal without a lot more information. This other information might include, size of island, nutritional requirements, habitat, population dynamics, behavior
        • "Pygmy" or dwarf mammoths have been found on islands from all over [nps.gov]:

          Pygmy populations derived from elephants or mammoths are known from several locations throughout the world, including the islands of Malta and Sicily in the Mediterranean, several islands in southeast Asia, and Wrangel Island in the Arctic.

          Nova did a nice little show about the Wrangel ones, if I remember right.

      • and things do not always go as typical - komodo monitors are from an island.
      • There are many theories running rampant about the so-called Hobbits, from misidentification to the reduced brain hypothesis. Many pressures in an isolated environment can create enough genetic pressure to lead to odd physical changes. Examples are twin studies of Andes Mountains dwelling children. When separated, one twin staying in the higher elevations and the other growing up at sea level researchers have noted drastic differences in the physical morphology. These observations hold true even though th
      • by Anonymous Coward
        Interestingly enough an Adam Brumm from the Australian National University has a different take than you. He says that the tools are actually very simple and the skills to make such tools had been developed on the island for over 800,000 years.

        It is amazing how many different opinions there are on the same facts:-)

        reference: http://news.bbc.co.uk/1/hi/sci/tech/5021214.stm [bbc.co.uk]
        • If he didn't say something else, it would hardly be hotly contested, would it? :) Besides, even when I was at University, Professors were forever disagreeing with me. Maybe it's something they're paid to do. :)

          I would point out an obvious flaw in his logic, though - in order for something to be under development for 800,000 years (as opposed to merely being used for 800,000 years), you should see signs of progress. That's obvious, right? Well, typically what constitutes progress with a stone tool is the abi

      • "Advanced stone tools" - isn't that right up there with 'huge midgets'?
        • Definitely maybe, but only always sometimes.

          Ok, ok, I'll be serious for a second - it depends on what you define "advanced" as being relative to. If you're talking in the context of stone tools, then your lowest level is a lump of rock picked up from the ground, and your highest level is the finest the stone will fracture repeatably combined with the best possible shaping for the purpose of the tool. If you picture this as an X-Y graph, where (0,0) is the lump of rock and the ideal is (M,N), draw two diagon

      • There is, however, one outstanding problem that has NOT been resolved. Dwarfism on islands is common with reptiles. Reptiles do NOT do islands well. However, mammals on islands tend towards giantism - Amblyrhiza Inundata (a giant rat the size of a grizzly) being an excellent example. Birds, although descended from reptiles, also seem to do well on islands - the Moa (a flightless bird that was 13 feet tall) and the Haast Eagle (the largest eagle that ever lived, with a wingspan of 14 feet), both from New Zea
        • Sounds right to me. Take the rocky Shetland Islands between the Scottish mainland and Norway - They seem to be a natural miniaturization lab, due to scarce resources - In TFA, they mention the miniaturization of deer brought over from the mainland to the Shetlands, and Shetland ponies, and Shetland sheep, herded by Shetland Sheepdogs (my breed of choice) are all well-known smaller variants of larger animals from elsewhere.
      • This is a common misunderstanding in the mechanisms underlying natural selection. It is not the case that there's just one direction that things inevitably go, or even in fact that there's a definitive pressure applied by a given type of environment. It is often the case that several contradictory pressures are applied at once, and in many cases a species branches to fulfill both of them.

        In fact, it's worth noting that all five of Earth's five biggest reptiles are in the setting that you suggest that they
  • by Bob Cat - NYMPHS (313647) on Thursday June 08, 2006 @02:31AM (#15492780) Homepage
    Someone was going to say it. Get it? Hartz Mountain Inc. sells bird seed? Little dinosaurs? No? I'll go back to Digg now...
    • Bravo! I was looking for the joke that you found. You ciphered it.

      But didn't you mean Canarydactyl?
      • No, if I were going to MINE the joke further, I would have referred to the "Pollydactyl". How about that? A cat + bird pun! (for people not from around here - a polydactyl cat is one with extra toes. Common in New England and some other places. Mrow.)
    • Lady, I'm going to tell you the same thing I told everybody else: I'm sorry if your dog went blind, but your beef is with Harz Mountain, not with me.
  • Let's get that cloning going and get some dinosaur racing going on! C'mon, what's cooler -- betting the ponies or betting the 'saurs?
  • Instead of the oxymoron "smallest giant", they should have said "smallest member of a family of dinosaurs whose other members are known to be giants, like the Brachiosaurus".
  • I like the image of an elephant the size of a St. Bernard as the article referred to (Komodo Dragon food, it said).
  • ObUnits (Score:4, Funny)

    by Scarblac (122480) <slashdot@gerlich.nl> on Thursday June 08, 2006 @04:17AM (#15493036) Homepage

    From TFA: "Their cousins, by contrast, were up to 45 metres long and weighed in at 80 tonnes - as much as a small town of over 1,000 inhabitants."

    I don't understand. How many Volkswagen Beetles is that?

  • Anyone ever notice how as you go further and further back in history animals get bigger and bigger compared to their present day counterparts? Like, you go back a little while and you have stuff like mastodons, saber tooth tigers, etc... Then you go back farther and you have stuff like dinosaurs... Trilobites are just like huge bugs... Doesn't anyone else find it weird, like maybe the bones are expanding as time passes or something? Anyways, I don't actually think this is true, I'm just randomly rambling,
    • by Anonymous Coward
      Not all trilobites are particularly large. Most, in fact, are about the size of today's arthropods. The main reason arthropods never get particularly big is that if they were much bigger than they are, their bodies wouldn't be able to hold their own weight. (When size doubles, strength increases by a square, but mass increases by a cube)
    • by MichaelSmith (789609) on Thursday June 08, 2006 @05:41AM (#15493224) Homepage Journal
      Anyone ever notice how as you go further and further back in history animals get bigger and bigger compared to their present day counterparts?
      • Big stuff lasts longer in the ground and is easier to see when you go digging
      • Human beings kill the biggest animals around for food, this being the most efficent way to get dinner. Over time big things become extinct.
    • My take is that a lot of it depended on the dominant plant life and carbon dioxide levels. Modern plants are more resistant to large herbivores. They also efficiently extract CO2 from the atmosphere (grasses in particular use a particularly efficient photosynthesis cycle). In addition, we're in the midst of a long period of ice ages (warm periods like now are infrequent).

      What I think this means, is that the modern environment is more hostile to huge plant growth and large herbivores than the eras of the d

    • That doesn't hold up for much of history. The Triassic era didn't have large dinosaurs, but the following eras (Jurrasic and Cretaceous) did. The dinosaurs got bigger as time went on, not smaller - Tyranosaurs were the last and largest of their line. There are plenty of examples of the reverse happening (large dinosaurs getting smaller, see Utah Raptors shrinking down to Deinonocus (Sp?) and Trodon), but there isn't a strong trend in that direction. It was the mass extinction at the end that got all the
    • There are lots of well known reasons for this. Most notably the size of animals, especially insects, varies depending upon the amount of O2 in the atmosphere. The composition of the earth's atmosphere has varied significantly over time.

      BTW, this is the real flaw with all time travel movies. If you bopped back to the age of the dinosours, you'd probably be dead within minutes as you might as well have jumped to a different planet. And dinosours's cloned back to like today would have to live in big bubb
  • Scientist's speculation of what the mini dinosaur might have looked like - picture [tvacres.com]
  • Small enough to have been a pet it seems.

    Did they note the suspicious remains of a Father-son-daughter "routine expedition" nearby? Any three fingered lizard men? Strange pylon with crysatls inside?
  • by J.R. Random (801334) on Thursday June 08, 2006 @03:25PM (#15496860)
    The article was slashdotted so I couldn't read it and this post is the usual Slashdot speculation. The smallest dinosaurs known were about the size of chicken. So I presume they meant this beast is the smallest known sauropod http://en.wikipedia.org/wiki/Sauropod [wikipedia.org]. Most sauropods were humungous, so a one ton adult would be very small.

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