Dinosaurs: Perfect Predators (DVD Review)

This is another Discovery channel DVD with a range of production dates. Although the DVD is dated 2011, the three programs contained are from 1997 through 2009.

The first, Dinosaurs: Perfect Predators, came out originally in 2009, so it is not too dated. However, it is totally unclear from the DVD that the three predators featured did not all live at the same time. T-Rex lived at the end of the Cretaceous, around 67 to 65.5 million years ago. Quetzalcoatius arrived a little earlier, though both were caught by the K-T extinction event 65.5 million years ago. Deinochychus, however, lived from 115-108 million ears ago in the early Cretaceous.

It is also worth pointing out that though Deinochychus (terrible claw) was 3 meters long, its back was less than a meter high, its weight was about that of a man, and it quite possibly had feathers. That does not mean it was other than a terrifying predator, especially in a pack.

The second program, Monsters Resurrected: The Great American Predator, deals heavily with trace fossils: a dinosaur trackway in Texas which has been interpreted as a two-legged predatory dinosaur, an Acocanthosaurus, taking down a large sauropod, a Paluxysaurus. Again, these are early Cretaceous dinosaurs, and would not have been alive at the same time as T-Rex. This program also dates to 2009. Both of the 2009 programs are a mix of paleontology and computer animation, but the science strikes me as superficial. (The footprint casting is of some interest.)

The third program, Beyond T-Rex, is quite old by dinosaur program standards and is focused mainly on paleontology. The “theme,” whether or not the discoveries of two large predators in the southern hemisphere “dethrone” T-Rex, struck me as rather silly. Yet in spite of its age (1997) this is probably the best of the three programs as far as paleontology is concerned.

The two dinosaurs discussed are Carcharodontosaurus (sharp-toothed lizard, apparently native to Africa)) and Giganonosaurus (giant southern lizard, Patagonia.) The two are very similar, and are much more closely related to Allosaurus and each other than they are to Tyrannosaurus. In fact, they are so similar that their distribution has been used to argue that there was still a land bridge between South America and Africa in the early Cretaceous, when these giants were alive. No mention is made of feathers, which is hardly surprising given the date of the programs, well before the feathered dinosaurs of Mongolia were discovered.

The history of Carcharodontosaurus is intriguing. The first specimens were found by German paleontologists before WWII, but were lost to allied bombing. More fossils were discovered in Morocco in 1995, and this material is the subject of the program. The casting of the skull is of considerable interest, as is the part of the DVD dealing with the rediscovery.

The discovery of Giganonosaurus in Patgonia is covered as well. Here a better idea of the live animal can be obtained from the BBC DVD, Chased by Dinosaurs, as one of the episodes involves a pack hut of Argentinosaurus by Giganonosaurus.

As a discussion of dinosaurs as predators the DVD is rather incomplete, especially the first two episodes. It may be worth getting if you want a complete collection of dinosaur videos.

Arctic Dinosaurs: DVD Review.

Dinosaurs in the Arctic? I live in Alaska and know several geologists, so I heard about the dinosaur bones on the North Slope almost as soon as they were rediscovered. My first reaction, years before this DVD was made, was, “what was the latitude at the time the dinosaurs lived there?” After all, the fossils were about seventy million years old, and plate tectonics has reshaped the continents and oceans considerably since that time. At first, the answer was “it hasn’t been checked yet,” but when it was checked, it turned out that the fossil location was even closer to the pole that it is now: probably at around latitude 80°.

Rediscovered? Turns out the bones were discovered clear back in 1961 by a Shell Oil geologist named Robert Liscomb. He sent them back to Shell, but when he was killed in a rockslide the following year, the bones were forgotten in the Shell archives. It was not until well into the 1980s and renewed interest in petroleum on the North Slope that the bones were sent to the Geological Survey, where they were first identified as being from a dinosaur.

None of which answers the question of how dinosaurs managed to live at a latitude where there was no sunlight for four months of the year, and no night for another four.

This DVD focuses on two questions. First, it examines the digging of a tunnel into the permafrost along the banks of the Colville River in an effort to find bones that were not broken up by freeze-thaw cycles. Second, it speculates on how dinosaurs managed to survive so near the pole. Were they migratory? What did they eat, especially in the winter? What ate them? What was the climate like? What does the discovery of dinosaurs at such a high latitude suggest about whether dinosaurs, like their bird descendants, were warm-blooded?

Certainly there is evidence for a climate far warmer than today’s on the North Slope, even though the latitude was higher. There is no evidence for sea ice that far back, and an open ocean would have made for a much warmer climate. But plants could not have grown without sunlight, so what did the herbivores eat? Moose today winter on bark and twigs – they certainly nipped all the buds off of my Amur maple last winter, and when I had a crab apple tree, it got smaller every year as the moose nibbled its twigs over the winter. Could dinosaurs have done the same?

Although this video does have some dinosaur animation of reasonable quality, it is of interest primarily for what it reveals about dinosaurs and their fossils. It was originally a TV program, from PBS on Nova. Get it for information, rather than entertainment.

The Essential Dinosaur Pack Disc 2: DVD Review

This disc, although it has a copyright date of 2008, is a collection of TV programs originally aired between 2003 and 2008. Thus none are really up to date.

“The Mystery Dinosaur,” from 2006, deals with the discovery of  “Jane.” This fossil has been variously identified as a Nanotyrannus and a juvenile Tyrannosaurus Rex. The program is primarily about the argument, which could date it, but as far as I can tell, the argument has never been resolved. Thus the program is still fairly current, though it is more science than entertainment.

“Dinosaurs: Return to Life” deals with the observations that the differences between dinosaurs and birds appear to be due to a relatively small number of mutations. Could birds be “reverse bioengineered” to produce something like dinosaurs? Would we really want to?

The four-program series “Dinosaur Planet” first aired in 2003, and unlike the rest of the programs in this set, it is definitely intended to be entertainment. Each of the four episodes focuses on one or two individual dinosaurs and follows them through a period of their lives. Each episode also covers something that is important or intriguing in the fossil record, and links back to that record. Thus “White Tip’s Journey,” featuring a Velociraptor,  suggests one explanation for the famed (real) fossil of a Velociraptor locked in a death struggle with a Protoceratops.

“Alpha’s Egg,” featuring the large sauropod Saltasaurus and the medium-sized predator Aucasaurus,  is based on the discovery of  a Saltasaurus nesting ground,  fossilized in Patagonia.

Pod of “Pod’s Travels” is based on a Pyroraptor,  a European raptor genus. The episode includes the natural hazards (earthquake, tsunami) that made occasional travel between the islands that made up Europe 80 million years ago possible. The focus of the program is on the dwarfing effect that islands tend to have on species. Pod is a Gulliver among Lilliputians when a tidal wave sweeps him to a much smaller island.

“Little Das’ Hunt” follows a juvenile Daspletosaurus  (an earlier close relative of Tyrannosaurus Rex) learning to hunt, and a herd of Maiasaura. The episode is based on a group of Daspletosaurus and Maiasaura found fossilized together in Montana, but the evidence for the kind of pack behavior shown in the episode is scanty and controversial.

Obviously there is a good deal of imagination going into the behavior, color, feathers or lack of them, musculature and behavior of all of these dinosaurs. Here I want to mention three, because they struck me so strongly.

The first is the underline of the creatures portrayed.  Theropod dinosaurs did indeed have a bone jutting back from the pelvis. However, the velociraptors are shown as having this bone stick out of the body, covered by a narrow wedge of tissue. It seems to me that this arrangement would be very susceptible to breakage, and that evolution would have reduced the length of the bone fairly fast. It makes much more sense that the tail and the posterior part of the belly were much deeper, with the projection buried in muscle. In fact a mummified hadrosaur had exactly this conformation, with a tail much deeper than anyone expected. Why not Velociraptor?

Second is the behavior of prey dinosaurs. Granted they didn’t have much brain, but instinct is also guided by evolution. Threatening a predator with teeth adapted to munching relatively soft leaves, and exposing the vulnerable neck in the process, does not make sense. Kicking (recent work has shown sauropods had vicious kicks) or tail swipes are far more reasonable for the big plant-eaters. This bothered me as far back as the Disney dinosaurs in Fantasia, when the stegosaurus turns to try to threaten T. Rex with its tiny mouth, instead of lashing out with its spiked tail. Now Disney may be forgiven – after all, Fantasia came out in 1940. Between making his dinosaurs animatable by artists drawing each cel by hand and the paleontological knowledge of the day, he did a respectable job even if his sauropods did have necks like snakes and his characters never actually lived at the same time. But that stegosaurus is pure theater, and Discovery Channel should have known better.

The third is grass. There is now some controversy over whether dinosaurs and grass coexisted, but the amount of grass shown is almost certainly incorrect.

Overall evaluation? Watch, but don’t believe everything you see. This DVD has a lot of creative interpretation, some of it almost certainly wrong.

The Essential Dinosaur Pack Disc 1 (DVD Review)

This set of two DVDs, although the cover has a date of 2008, in fact combines episodes originally aired on the Discovery Channel from 2001 to 2008. The first disc contains four episodes:  Valley of the T. Rex (2001), T-Rex: New Science, New Beast (2006), When Dinosaurs Roamed America (2001) and Utah’s Dino Graveyard (2005). Keep the true dates straight, because our interpretation of dinosaurs is changing rapidly, and the episodes at times seem to contradict each other. None of the interpretations are truly currant, or represent today’s ongoing controversies.

This DVD focuses on the processes of finding, unearthing and interpreting fossils, with only minor clips of computer generation of the living animals. It will be of more interest to budding paleontologists than to those looking for entertainment.

Valley of the T-Rex looks at the idea put forward by Jack Horner that T-Rex was primarily a scavenger, not a predator. The idea is hardly new, and is far earlier than the discovery of T-Rex’s tiny arms – Wiley Ley proposed it as a science article in the April 1943 issue of Astounding Science Fiction. I really doubt that there is any such thing as a pure predator or a pure scavenger. Any predator will scavenge a fresh kill, and any scavenger will kill an animal down and helpless, if only by eating it. Like the short-faced bear, T-Rex may have used its impressive size to intimidate other predators off their kills, but that doesn’t mean it never killed.

T-Rex: New Science, New Beast is more balanced, mentioning that how T-Rex fed is controversial but not getting into the controversy. Rather, it summarized new (as of 2006) methods of investigating dinosaur fossils. This included learning how to tell how old fossil dinosaurs were at death (which led to the discovery of the fantastic teenaged growth spurt of T-Rex and the relatively young age (29) of Sue, the largest T-Rex found.) At least one dinosaur was sexed, though the technique only works with pregnant (with eggs) females. Study of locomotion in modern animals has been applied to dinosaur skeletons, suggesting a lower top speed for full-grown T-Rex than was previously estimated. The episode also mentioned the discovery that some fossil bone had collagen, study of T-Rex bite strength, and the discovery of feathered theropods, leading to the possibility that T-Rex juveniles, at least, had downy feathers.

When Dinosaurs Roamed America goes through the history of dinosaurs, using an American location to spotlight each time period. Remember this segment, and the computer animated clips included, is eleven years old in 2012.

The video starts with New York (Permian-Jurassic, first dinosaurs, early opening of the Atlantic.) It then moves on to Exeter Township, PA (Triassic-Jurassic boundary, theropod-sauropod split.) Utah was a savannah 150 million years ago, wandered over by giant sauropods, their predators, and the smaller herbivorous dinosaurs that survived at their side. New Mexico 90 million years ago was a tropical swamp, with an explosion of flowering plants and broadleafed trees. The notorious K-T (Cretaceous-Triassic) boundary and the final extinction of the dinosaurs is investigated in South Dakota. The video is not bad, but dated.

The final program, Utah’s Dino Graveyard, covers a single location with a huge number of dinosaur fossils of a single species. Falcarius Utahensis was a strange beast even by dinosaur standards, as are most of its Therizinosaurian relatives. It is one of the earliest of a group that evolved from raptor-like carnivores to big-bellied but still relatively upright herbivores. This does happen – all dinosaurs, even the huge sauropods such as Apatosaurus evolved from early ancestors that ran on two legs and preyed on insects. More recently, the giant panda seems to be a bear that has embraced a diet of bamboo.

The real question is, what killed large numbers of the same species? Their preservation seems to be due to the fact that they all died near ancient springs, with rock from the spring deposits forming a cap that preserved their bones, but could the spring also have played a role in their deaths?

In general the computer graphics are adequate but not inspired, and at times show behavior I have doubts about — but I’ll save that critique for the second disc.

Dinosaurs Inside and Out: DVD Review

This is actually a reissue of programs aired on the Discovery Channel in 1997, though the DVD has a 2009 date. The package date is very misleading, as both the facts given and the computer animation are 15 years old – before the first airing of Walking With Dinosaurs. The computer animation, in particular, is very poor, and I would certainly not buy this DVD to watch the dinosaurs!

The DVD includes four 1-hour programs: Renaissance of the Dinosaurs, Land of the Giants, The Killer Elite, and And Then There Were None. In order, they deal with the public fascination with dinosaurs, the large herbivores, the two-legged killers such as T-Rex and raptors, and the extinction of the dinosaurs.

Luckily, the program concentrates not on the videos, but on the science of paleontology. Even that is a bit dated in describing what is known about dinosaurs, though the finding, excavating, packing and cleaning of specimens is worth watching for budding paleontologists. So is the history of our fascination with dinosaurs, including more than the usual information about how our views about dinosaurs have changed since the Crystal Palace reconstruction and the dinosaur wars between Cope and Marsh.

If you are looking for a video to entertain children, this is not it. On the other hand, the DVD does have a number of airings of scientific controversies and field operations.

One point I would disagree with. The question of whether dinosaurs resembled birds or reptiles in care of young is addressed by using fossil bone cross sections to determine whether newly hatched dinosaurs had strong enough legs to stand. I strongly suspect that some dinosaurs could stand and some couldn’t, and the same is true of modern birds. Certainly chicks and ducklings are on their legs and finding their own food almost at once, and I suspect at least some dinosaurs may have been the same. I have seen arguments in later DVDs that some pterosaurs (which admittedly are not dinosaurs) were able to fly shortly after hatching.

All in all, this is not a DVD I would consider entertainment, but it could be of interest to a budding paleontologist.

IMAX T-Rex: DVD Review

Back when IMAX theaters were rare and found mostly in museums I went to a 3-D IMAX show – T-Rex – at the Smithsonian Natural History Museum. Even then I found it a peculiar amalgam of three-dimensional animation, paleontology, and not-very-good science fiction. (OK, it’s pretending to be science fiction, but it’s closer to bad fantasy.)

I got the DVD a while back, when I was getting most of the dinosaur videos available.

It’s a 1998 movie, and of course a lot has been learned about T-Rex in the intervening 14 years. Not enough, however, to make me feel like trying to pet one, or think it was capable of gratitude to another species!

Both the animation and the sequences of paleontologists in the field are fascinating, and so is the information about museum displays and Charles Knight. If the producers had stuck to the informational part, and perhaps used the idea of T-Rex as a nurturing mother in a more reasonable way, this could have been an excellent film, though a short one (44 minutes.) However, they insisted on adding a plot which involved something that left the audience guessing whether dreams, hallucinations, or time travel was involved. The supposed resolution, with a paleontologist finding a 20^th century watch, was totally ridiculous. Complex metal objects like watches simply do not fossilize.

Further, neither the big-screen of IMAX nor the 3-D were available in the DVD I have. This was a movie which depended on these effects.

Interestingly, there is considerable current research on the extent to which tyrannosaurs might have lived and hunted in family groups, and it is generally recognized today that birds are fundamentally modern dinosaurs, descended from the same bipedal group to which T-Rex belonged. The DVD, watched with the production date in mind, does give some interesting information on the history of how we think about dinosaurs. Just forget the plot!

p.s: As an update on last week’s post about ice jam floods, there is still a flood warning out for the Salcha River area, and the ice went out at Nenana at 7:39 yesterday evening. This can happen from April 20 to May 20, so breakup this year was early.

Allosaurus: DVD Review

This is a Walking With Dinosaurs program, and like most of that group the animation is excellent, even though the narration tends to present guesswork as fact. Case in point: the red color above the eyes, mentioned as a sign of sexual maturity. To the best of my knowledge (and it was certainly true in 2000, the copyright date) both color and possible significance are pure speculation.

The story follows the life of an Allosaurus, “Big Al,” as reconstructed by forensic analysis of the bones of one of the most complete Allosaurus fossil skeletons ever discovered. I found the second half of the video, which deals with the actual forensic analysis, even more interesting than the fictionalized video of Al himself.

Al was certainly a “live fast and die young” dinosaur. His bones are remarkable not only for being found relatively complete, but for the number of healed injuries they show. How did he get those injuries? The main program gives possible reasons, though of course things may not have happened exactly as shown. But we know he survived broken bones that had time to heal completely and a toe infection that must have lasted for months before his death.

I would like to make two points about dinosaur DVDs in general. First, our knowledge of dinosaurs is changing so fast that is essential to know the dates at which the videos were made! Dates on the cover of DVDs made up from programs originally broadcast on television can vary widely from dates of the original broadcasts. This one’s from 2000; I’ll go back as I find the actual copyright dates on the individual programs and add them to earlier reviews.

Second, for some reason animators feel compelled to have their dinosaurs roaring (or making other sounds) at every opportunity. Now animals do make sounds, and we certainly expect dinosaurs did. But predators, in particular, make sounds at particular times for particular reasons. They may communicate with sounds. They may warn off rivals, or try to intimidate them. They may call to attract mates. They may make sounds to deliberately panic prey. They try very hard not to make a sound when they are trying to stalk prey! Certainly they do not hiss, growl, or roar while setting up an ambush!

All in all, this DVD is worth watching if you want to watch dinosaurs in action, or see what the state of dinosaur science was in the 20^th century. Just keep in mind when it was made.

Bizarre Dinosaurs DVD Review #IAN1

All dinosaurs are bizarre, by mammalian standards. Some, however, are bizarre even to paleontologists, and the title program of this DVD is devoted to them. There is, however, a secondary program, not even mentioned on the cover, which to me was of considerably more interest.

Most of these animals are considered bizarre because they have appendages, preserved in the fossil record, that leave paleontologists wondering just why these animals have that appendage. Take the 33 foot-long Anargasaurus, for instance. Why on earth did this plant-eater have a double row of bony spines down its back? Reconstructions tend to show it with skin forming a double crest supported by those spines, but why? The only answer anyone had come up with is some kind of display crest, like the peacock’s tail.

Display organs are common, especially in today’s birds (which after all are modern dinosaurs) so I suppose it’s as good an explanation as any for such things as the plates of a Stegosaurus (which would have been potato chips to a large carnivore) or for the fanciful neck frills, often richly supplied with blood, of the Ceratopsids. Were horns used to fend off predators, of for fighting off rivals within the species? Or just for display?

In some cases the peculiarities might be associated with feeding. Take the Epidendrosaurus, for instance, a sparrow-sized dinosaur with an incredibly long third finger. Did it use its long finger as the aye-aye in Madagascar today does, to find insects in the bark of trees? Then there’s Nigersaurus, with a broad, flat head with a very wide muzzle resembling a vacuum-cleaner nozzle. Did it stand in one place and hoover up the vegetation?

This DVD is less interesting than most of the National Geographic programs scientifically, but it does show some interesting dinosaurs. If you want information on some of the animals shown, National Geographic has both an interactive site and a magazine article by John Updike.

The secondary program, which was a total surprise, should have been part of the Prehistoric Predators DVD I reviewed earlier. It was concerned with a much more recent animal, one I’d met before in Prehistoric Park—a predatory, flightless bird that could almost hold its own with sabertoothed cats and dire wolves. Certainly it seems to have taken down the same kind of prey.

These terror birds were not what you want to attract to your backyard bird feeder! Imagine an oversized ostrich with the hooked beak of a raptor, that beak (and head) enlarged to the size of a rather large war axe. With ostrich speed and taller than a man, they evolved to be the top predators on the South American continent, for many millions of years an island continent. Then a few million years ago, the isthmus of Panama joined it to North America, ending the isolation in which the terror birds had evolved. Animals crossed the new isthmus both ways. Opossums, armadillos, and porcupines moved north, but a far greater number of placental mammals moved south.

Surprisingly, a few terror birds did move north, as their fossils have been found in Florida. Did they meet with the earliest humans to colonize North America? Or were they simply unable to compete with the mega-predators already here? They did seem to survive for a long time in North America, but the jury is still out on just how long they lasted.

Tomorrow’s the day to look at quotes from Lewis Carroll, but I’ll also have a guest appearance on another blog, Christine’s Words. Stop by!

Dinosaurs Unearthed: DVD Review

This is the first of a number of reviews of National Geographic’s DVDs on prehistoric animals, so I will start out by saying something that applies to all. They are very good in interviews with actual paleontologists. The computer graphics of the extinct animals are of moderate quality, and there are only a few clips repeated over and over again. These videos are excellent for budding paleontologists or those actually interested in the science of how we know about extinct animals, and are better than series like “Walking With Dinosaurs” in that they allow scientific arguments to be heard. They are not in the same league when it comes to the re-creation of the extinct animals.

This DVD contains two programs originally shown on the National Geographic channel: Dino Autopsy and Dino Death Trap. The first is about a rare fossilized mummy of a hadrosaur, nicknamed “Dakota,” found in the badlands of North Dakota. The fossil was found in 1999 by a teenaged paleontologist, and has supplied information on skin texture and musculature of hadrosaurs. The science is fascinating. The quality of the animation is somewhat less so.

The second program involves the excavation of a site in China. This site produced a number of near-complete skeletons from a period, the Late Jurassic, very poorly represented until now. Most of the attention is given to Guanlong, a very early form of tyrannosaurid. The skeletons are in three dimensions rather than flattened, which has been interpreted as evidence that they were trapped in soft sediments, and lie above each other in a vertical column.

There is speculation about how they died included in the video. Was a volcanic eruption to blame? Was the mud in which they were trapped due to volcanic ash falling into a marsh? Also, while these animals are the early forms of species known from the Cretaceous, the Cretaceous forms were giants, and these animals are relatively small. Guanlong’s back would about reach the waist on a standing human, yet it is an early relative of Tyrannosaurus Rex. What caused the increase in size? Did guanlong really have feathers as part of its crest? They are in the computer animation, and a relative, Dilong, is known to have had primitive feathers. The crest does appear to be a display organ (relatively thin and brittle) and feathers would have made it more conspicuous.

Overall the DVD is worth watching if you are really interested in dinosaurs. If you are looking primarily for entertainment, others are better.

DVD Reviews

Here, all in one place, are links to my reviews of some of my favorite DVDs.
This list will be linked from the Index page, and I’ll be adding to it as new DVDs are reviewed.

Understanding the Human Factor (Great Courses) 6/12/10
Beauty and the Beast 3/24/11
Chased by Dinosaurs 4/26/11
Prehistoric Park 5/3/11
Before the Dinosaurs 5/10/11
Walking with Dinosaurs 5/24/11
Walking with Prehistoric Beasts 5/31/11
Inside Planet Earth 6/7/11
Dinosaurs: Extreme Survivors 6/14/11
Madagascar (Attenborough) 6/21/11
How the Earth was Made Season 1 7/5/11
Brigadoon 8/23/11
Singin’ in the Rain 9/27/11
Cats 10/11/11
How the Grinch Stole Christmas 11/29/11
Tchaikovsky’s Nutcracker Ballet 12/6/11
A Christmas Carol (Disney) 12/13/11
Hogfather 12/20/11
The Future is Wild 12/27/11
Dinosaurs Unearthed 1/10/12
Prehistoric Predators 1/17/12
Skywatching (Great Courses) 1/24/12
Sky Monsters 1/31/12
Bizarre Dinosaurs 2/7/12
Oceanography (great Courses) 2/14/12
Cinderella 2/21/12
The Four-Winged Dinosaur 4/3/12
Allosaurus 4/10/12
Pride and Prejudice 4/17/12
IMAX T-Rex 4/24/12
Dinosaurs Inside and Out 5/8/12
Essential Dinosaur Collection, Disc 1 5/15/12
Essential Dinosaur Collection Disc 2 5/22/12
Arctic Dinosaurs 5/29/12
Dinosaurs: Perfect Predators 6/5/12
Waking the Baby Mammoth 6/12/12
Frozen Planet 6/19/12
Those Magnificent Men in their Flying Machines 6/26/12
Those Daring Young Men in their Jaunty Jalopies 7/3/12
The Great Race 7/31/12
Invitation to the Dance 8/21/12
Pride and Prejudice with Kiera Knightly 2/12/13
Mansfield Park (BBC 1986) 2/11/14
Mansfield Park 4/15/14
Birth and Death of Stars 4/22/14
Mansfield Park (2007) 6/10/14