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.

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.

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.