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A reconstruction of Tyrannosaurus rex on display at the National Museum of Natural History. Photo by the author.

I can’t help feel bad for Tyrannosaurus. The dinosaur’s relatively minuscule arms are a near-constant source of ridicule. It doesn’t matter that there were other fearsome predatory dinosaurs with even smaller and apparently useless arms—the short arms of the “tyrant king” are a cruel evolutionary joke.

All the same, the tumblr blog T-Rex Trying… is a whimsical line-drawing catalog of all the things Tyrannosaurus couldn’t do with those small arms. Everything from cross-country skiing to simply counting to five would have posed a challenge, although I think my personal favorite is Tyrannosaurus trying to navigate the sneeze-guard at a buffet. Although such a scenario assumes that Tyrannosaurus would have had the manners to stand in line for the steam-tray fare and would not have gobbled up the bacon- and potato-stuffed clientele….

About 110 million years ago, an ankylosaur settled on the bottom of a Cretaceous sea. This was no place for a dinosaur. No dinosaurs were adapted to a marine lifestyle, and the heavily armored ankylosaurs were probably the least suited to paddling around in the water. Yet, almost a year ago, shovel operator Shawn Funk found an ankylosaur in the marine, Early Cretaceous sediments at a Suncor mine in northern Alberta. How did the dinosaur get there?

Donald Henderson, curator of dinosaurs at the Royal Tyrrell Museum, explained how this dinosaur died, was preserved and was discovered in a recent lecture for the Royal Tyrrell Museum Speaker Series. Almost everything about the discovery was lucky. The dinosaur just happened to settle in a place where sediment quickly covered its body; the carcass was not torn apart by scavengers; the shovel operator who stumbled across the ankylosaur recognized that he found something potentially significant and the discovery of the dinosaur in the mine meant that paleontologists had lots of heavy machinery on hand to help excavate the skeleton.

But the strangest aspect of the find is the ecological context of the dinosaur. This ankylosaur must have lived along the coastline of the great Western Interior Seaway which once split North America into two. But that was many, many miles away from where the skeleton was found. Exactly how the dinosaur died is unknown, but as Henderson notes, the carcass undoubtedly floated upside-down through the sea. The gases from decomposition gave the body enough buoyancy to travel—what paleontologists commonly refer to as a “bloat and float” scenario.

Dinosaur, Colorado's bizarre, long-snouted Triceratops. Photo by author.

Last week I asked you submit your favorite atrocious roadside dinosaurs. While the sculptures along the main drag of Dinosaur, Colorado come close to the top of the list, my vote last week went to the ugly, ugly dinosaurs outside Stewart’s Petrified Wood near Arizona’s Petrified Forest National Park. Readers sent in a few additional contenders for the title.

Photo by Mark Ryan.

Reader Mark Ryan sent in this sad, decaying dinosaur that stands near Interstate 15 in the vicinity of Victorville, California. No wonder the dinosaur needs those metal rods to support itself—its legs look like they’re made of cooked noodles.

Cowboys and dinosaurs, spotted in Natural Bridge, Virginia. Photo courtesy Kathy Krein.

A regular favorite of Dinosaur Tracking readers is the truly strange Dinosaur Kingdom in Natural Bridge, Virginia. Suggested as a top choice for weird dinosaurs by reader Laura Wilson, this tourist trap features a peculiar southern mash-up of dinosaurs and the Civil War—Union Soldiers are chomped on and terrorized by Mesozoic monstrosities. This particular shot, sent in last year by Kathy Krein, features a rather surprised looking cowboy who looks as if he’s only just begun to realize that riding a deinonychosaur was a horrible decision.

Photo by Kelly Enright.

Reader Kelly Enright sent in a set of several dinosaurian abominations from around the country. This one, complete with glowing eyes, stands guard over Goony Golf in New York.

Photo by Kelly Enright.

While not actually a dinosaur, this boxy mosasaur outside Big Mike’s Rocks & Gifts in Kentucky deserves an honorable mention, especially since the poor thing is stranded hundreds of miles from the nearest ocean.

Photo by Kelly Enright.

While not the absolute worst dinosaur I have ever seen, this Tyrannosaurus at the entrance to Kentucky’s Dinosaur World is one of the creepiest. So if the head is up there, and the legs are on either side, what part of the dinosaur am I walking into, exactly?

Photo by Kelly Enright.

We may have a new winner! While this automotive Triceratops—I think?—from Hanksville, Utah does win some bonus points for recycling, my first thought when I opened the image was “Oh geez! Kill it with fire!” This dinosaur is a junkyard nightmare, and surely a top contender for the worst roadside dinosaur ever.

There’s no shortage of dinosaur encyclopedias. From technical volumes to children’s picture books, dinosaur catalogs have proliferated in both dead-tree and e-book formats. Among the slew of titles, though, the newly-released Inside the World of Dinosaurs for the iPad looks to be one of the prettiest offerings.

The major hook for the new app is a wealth of computer-animated dinosaurs. A total of 60 prehistoric creatures—mostly dinosaurs with a few non-dinosaurian Mesozoic favorites among the lot—are put through their paces in animated walk cycles and re-enacted battles. Aside from common paleo quibbles—the Deinonychus have “bunny hands” and their feathers are not well realized—the artwork seems to be on par with any dinosaur documentary you’re likely to see on television today. And you can browse through this prehistoric menagerie in different ways, including a timeline which places dinosaurs in their chronological order (a nice feature since the “Age of Dinosaurs” is too often viewed as block of time where Triassic, Jurassic and Cretaceous periods are smashed together.) A bonus is narration by Stephen Fry, the British actor who recently narrated March of the Dinosaurs.

Sadly, though, the app is only available to those with an iPad. I don’t think I could justify the purchase another piece of expensive hardware just to play with dinosaurs. If you have tried out this app, though, let us know what you think in the comments.

A parent Massospondylus attends to its hatchlings. Art by Julius Csotonyi.

Two years ago, paleontologist Robert Reisz and colleagues revealed that the Early Jurassic dinosaur Massospondylus started off life as an awkward little thing. An exceptional set of eggs recovered from South Africa in 1976 contained the well-preserved skeletons of these baby dinosaurs, and the infants did not look very much like their parents. A roughly 20-foot-long adult Massospondylus had an extended neck and a long, low skull and it walked on two legs. But a baby of the same dinosaur had a short neck, a big head for its body, and it walked on all fours. The change between baby and adult was fantastic, and now, in a new PNAS paper, Reisz and colleagues provide an even more detailed look at how Massospondylus started life.

In 2006, Reisz and collaborators located the site where the Massospondylus eggs had been discovered in South Africa’s Golden Gate Highlands National Park. They found more eggs and baby dinosaurs, but not just that. About 190 million years ago, this place was a nesting ground that multiple Massospondylus used from one season to the next.

The paleontologists have discovered bones, eggshell fragments and ten egg clutches—the largest has 34 eggs—within a six-and-a-half-foot swath of siltstone. These nest sites were not all found in the same level, demonstrating that this particular place was used multiple times by Massospondylus moms. Despite the fact that this place was a nesting ground, however, there does not appear to be any evidence that the parent dinosaurs made special accommodations for the eggs—no clear sign of bowl-shaped depressions or other hints of nest construction were found.

Exactly how much parental care adult Massospondylus offered their babies is unknown. Crocodylians and many birds—the closest living relatives of dinosaurs—often attend their nests from the time the eggs are laid and guard their offspring for at least a short interval after their babies hatch. Massospondylus may have done the same, and small tracks found in siltstone blocks indicate that hatchling dinosaurs remained in the nesting site after emerging from their eggs. The tiny hind- and fore-foot tracks are about twice the size of what would be expected for a newly-hatched Massospondylus, and so it seems that the babies stayed at the site until they doubled in size, at least.

The setting of the nesting site allowed all these intricate details to be preserved. In the time of Massospondylus, the site was a relatively dry habitat near the margin of a prehistoric lake. Relatively gentle flooding events covered up the nest site with fine-grained sediment, and afterwards the area dried out. This was a regular, seasonal cycle, and the bad timing of some expectant dinosaur parents resulted in the good fortune of the paleontologists.

With this new data point, Reisz, Evans, and co-authors looked at the big picture of dinosaur reproduction to see which traits might be widely shared and which might be specializations. It seems that communal nesting sites that were used over and over again was an old, common aspect of dinosaur behavior. And, regarding sauropodomorphs specifically, the Massospondylus site may provide some insight into the evolution of different reproductive behavior among its larger sauropod cousins. Evidence from some sauropod nesting sites has been taken to suggest that exceptionally large long-necked dinosaurs did little more than lay eggs and leave their offspring to fend for themselves. What the Massospondylus site might indicate is that the “lay ‘em and leave ‘em” strategy was not the ancestral state for these dinosaurs, but instead was a reproductive specialization related to increasing body size.

So far, this is the oldest known dinosaur group nesting site. Similar sites created by hadrosaurs and sauropods are about 100 million years younger—a vast expanse of time. Potentially earlier nest site finds have not been well studied. One such Late Triassic site in Argentina has yielded multiple infant and juvenile specimens of the sauropodomorph Mussaurus. I asked David Evans, a paleontologist at the Royal Ontario Museum and one of the co-authors of the new study, about the possibility that the Mussaurus locality is an even older nesting ground. “[E]vidence of any form of extensive nesting site [at the Mussaurus localities] is very scant,” he said, but noted that “given our luck in South Africa, I would not at all be surprised if there are a bunch of nests similar to what we have [found] at the Mussaurus localities too—someone just needs to look and document.”

References:

Pol, D., & Powell, J. (2007). Skull anatomy of Mussaurus patagonicus (Dinosauria: Sauropodomorpha) from the Late Triassic of Patagonia Historical Biology, 19 (1), 125-144 DOI: 10.1080/08912960601140085

Reisz, R., Evans, D., Roberts, E., Sues, H., & Yates, A. (2012). Oldest known dinosaurian nesting site and reproductive biology of the Early Jurassic sauropodomorph Massospondylus Proceedings of the National Academy of Sciences DOI: 10.1073/pnas.1109385109