GONE BUT NOT FORGOTTEN
Welcome to The Deep science and technology column where we cover topics from the deep sea to deep space and beyond.
Greetings everyone! Well, the animal file is beginning to bulge and we’ve got several stories of animals both living and dead in strange and unexpected places.
WHAT’S UNDER YOUR PARKING LOT?
When most of us think about animal research, we think about it happening in far-distant and inhospitable places like jungles. When most of us think about animal fossils, we get the same mental pictures, but this time, it’s wind-blown deserts that spring to mind. We don’t associate either endeavor with big cities.
But that certainly doesn’t include one of the world’s richest fossil fields; smack in the middle of one of the world’s biggest cities; Los Angeles California. In addition to being famous for movies stars and huge brush fires and earthquakes, the city of angels is also home to the La Brea Tar Pits.
The Page Museum at the La Brea Tar Pits, has recently made a discovery so huge it could potentially rewrite the scientific account of the La Brea Tar Pits and their surrounding area—one of the richest sources of information about life in the last Ice Age.
The La Brea Tar Pits are located in the heart of downtown Los Angeles. (If Los Angeles can be said to have a ‘downtown’. Dorothy Parker once said that Los Angeles was 72 suburbs in search of a city.) I’ve been there and it’s an astounding place; a park surrounded by tall buildings.
The new project has uncovered over 700 specimens including a large pre-historic American Lion skull, lion bones, dire wolves, saber-toothed cats, juvenile horse and bison, teratorns (a huge fossil bird), coyotes, lynx, and ground sloths. The most exciting find is a well-preserved male Columbian mammoth fossil, about 80% complete, with 10-feet long intact tusks. This is the first complete individual mammoth to be found in Rancho La Brea. The paleontologists at the Page Museum have nicknamed the mammoth “Zed.”
The Page Museum at the La Brea Tar Pits is famous for one of the world’s largest and most diverse collections of Late Pleistocene fossils—objects so important that the last 300,000 years of the Pleistocene is known to scientists as the Rancholabrean Land Mammal Age. Paleontologists at the Page Museum now estimate that the new research project (called Project 23) could increase the collection by three to four million specimens.
So, where did this astounding raft of discoveries come from? Well, when the Los Angeles County Museum of Art began construction of some new buildings they discovered some interesting things. They were so interesting that under the guidance of Page Museum scientists, 23 enormous intact blocks were lifted out of the ground. They were encased in wooden boxes that ranged in size from 5×5x5 feet (weighing 3 tons) to 12×15x10 feet (weighing 56 tons). Project 23: gets its name from the reference to the number of extracted crates—with each box bearing its own number (1-23).
Rather than beginning at ground level and digging into the asphalt ooze or “tar pits” to expose trapped specimens as they’ve done for the last century, Page Museum paleontologists will begin their Project 23 excavations at the top of each block. In addition to the many mammal fossils, the researchers have also discovered turtles, snails, mollusks, lots of tree trunks and complete insect and leaf mats, all of which are expected to provide important environmental data.
Exposed left acetabulum of Zed’s pelvis. The fossil is from the first complete individual mammoth to have been found in Rancho La Brea. (Credit: Photo courtesy of the Natural History Museum of Los Angeles County)
Just goes to show you that there could be anything lurking beneath your feet. Although we don’t have traditional fossils here on Guam (no dinosaurs: Guam didn’t come out of the water until millions of years after they were gone (maybe, more on that later!) you can certainly make the argument that all of northern Guam is, in fact, one gigantic fossil because northern Guam is all the remnants of massive coral reefs.
You expect coral reefs here, we are in the tropics and that’s where all the corals live? Right? Well, apparently not. Read on!
WE TOOK A WRONG TURN AT THE CANARY ISLANDS!
In a stunning new discovery, researchers from the University of Galway have recently confirmed the existence of a major new coral reef on the southern end of the Porcupine Bank off the west coast of . . . (wait for it!) . . Ireland. The surveyed area is about 80 square miles and contains at least 40 carbonate mounds covered with coral. These underwater hills rise as high as 300 feet above the seafloor.
Now in case your geography is a little rusty, Ireland lies at 53 degrees north, which is a serious distance beyond the 20 degrees north to 20 degrees south span that’s called the ‘tropics’.
The deep-water expedition took place aboard the research vessel, the RV Celtic Explorer. The scientists used the remotely operated vehicle (ROV) Holland I to survey the seafloor and capture unique video footage.
One of the researchers, Dr Anthony Grehan said: “These are by far the most pristine, thriving and hence spectacular examples of cold-water coral reefs that I’ve encountered in almost ten years of study in Irish waters.
The expedition began in French waters with a series of ROV dives in previously unexplored canyons in the Bay of Biscay which confirmed the presence of coral reefs in that location in the Atlantic. When the ship moved into Irish waters the researchers used high resolution bathymetry charts, provided by the Irish National Seabed Survey to identify new areas likely to support coral reefs. The Holland I was then used to dive on one of these areas, the Archipelagos Mounds (or Arc Mounds), where it revealed a seascape of spectacular coral reefs.
Dr Grehan also noted that vulnerable marine ecosystems such as coral reefs represent one of the last untapped reservoirs of potentially useful bio-compounds that might support the development of new anti-viral or anti-bacterial pharmaceuticals.
A large Phycis sp. feeding on a smaller fish with ROV arm visible in bottom right of shot. (Credit: Dr Anthony Grehan, Earth and Ocean Sciences, NUI Galway)
And whoda thunk they’d have found one of these untapped reservoirs off the coast of Ireland??
So, I said earlier, Guam came up out of the water millions of years after the dinosaurs were all gone. That’s probably still true but there’s increasing evidence that perhaps the dinosaurs weren’t all gone exactly when we thought they were!
HANGING ON
The Lost World, Sir Arthur Conan Doyle’s account of an isolated community of dinosaurs that survived the catastrophic extinction event 65 million years ago, is still as appealing now as it was when it was written a century ago. Various Hollywood versions have tried to recreate the lost world of dinosaurs, but today the fiction seems just a little closer to reality.
New scientific evidence suggests that dinosaur bones found in the Ojo Alamo Sandstone in the San Juan Basin date from after the extinction, and that din
osaurs may have survived in a remote area of what is now New Mexico and Colorado for up to half a million years after their counterparts disappeared. This controversial new research is based on detailed chemical investigations of the dinosaur bones, and evidence for the age of the rocks in which they are found.
"The great difficulty with this hypothesis — that these are the remains of dinosaurs that survived — is ruling out the possibility that the bones date from before the extinction," says Jim Fassett, author of the research.
It is possible for fossilized bones to be excavated by rivers and then incorporated into younger rocks. That’s not the usual way fossil deposits form, but it’s been shown to explain some other ‘post-extinction’ dinosaur bones. However, Fassett has amassed evidence that indicates these fossils from the Ojo Alamo Sandstone were not excavated and redeposited and that these dinosaurs really did live after the Cretaceous extinction event.
To amass this evidence you must first demonstrate the rocks containing the bones are younger than the extinction event. Fassett has analyzed the magnetic polarity of the rocks, and the pollen grains they contain, different approaches to dating rocks from which he concludes that both indicate the rocks are younger than the extinction.
Fassett also found that the dinosaur bones from the Ojo Alamo Sandstone have distinctly different concentrations of rare earth metal elements than bones found in the underlying Cretaceous rocks. He argues that these concentration differences make it unlikely that the post-extinction bones were exhumed from the underlying sediments. This is also supported by a find of 34 hadrosaur bones. Although they weren’t an articulated skeleton, they are doubtless from a single animal. Fassett maintains that if the bones had been exhumed by a river, they would have been scattered.
So does this provide proof that dinosaurs survived the Cretaceous extinctions? Finding conclusive evidence is a difficult matter when the crime scene is 65 million years old. One thing is certain, if dinosaurs did survive, they weren’t as widespread as they were before the end of the Cretaceous and they didn’t persist for long. The ‘Lost World scenario’ of humans and dinosaurs existing at the same time (or dinosaurs on Guam) still belongs firmly in the realms of pure fantasy.
View eastward from divide between Ojo Alamo and Barrel Spring arroyos, Kirtland shale in foreground. (Credit: Plate 71-A in U.S. Geological Survey / Bauer, C.M. 251)
