Rhino Horns Explained

Structure of white rhinoceros (Ceratotherium simum) horn investigated by X-ray computed tomography and histology with implications for growth and external form. 2006. Tobin L. Hieronymus et al. Journal of Morphology 267: 1172 – 1176.

New research from the Witmer Lab explains how the horn gets its distinctive curve and sharply pointed tip.

From the Ohio U press release:

The horns of most animals have a bony core covered by a thin sheath of keratin, the same substance as hair and nails. Rhino horns are unique, however, because they are composed entirely of keratin. Scientists had been puzzled by the difference, but the new study has revealed an interesting clue: dark patches running through the center of the horns.

Researchers conducted CT scans on the horns and found dense mineral deposits made of calcium and melanin in the middle.



The calcium deposits make the horn core harder and stronger, and the melanin protects the core from breakdown by the sun’s UV rays, the scientists report. The softer outer portion of the horn weakens with sun exposure and is worn into its distinctive shape through horn clashing and by being rubbed on the ground and vegetation.

The study also ends speculation that the horn was simply a clump of modified hair.

“The horns most closely resemble the structure of horses’ hoofs, turtle beaks and cockatoo bills” said Tobin Hieronymus, lead author on the study.

Download the PDF HERE

Visit the Witmer Lab page for more info on Rhinoceros Horn Growth & Form.

Rhino Statue from Bowen Designs

Died This Day: Henry Fairfield Osborn

August 8, 1857 - November 6, 1935

Osborn graduated at Princeton in 1877 and pursued his interest in the biological sciences and paleontology through additional study at several New York City medical schools and with Thomas Henry Huxley in Britain. Returning to the United States, Osborn accepted a position at Princeton, teaching natural sciences from 1881 until 1891, when he moved to Columbia University to organize the Biology Department there, and in 1891, he also helped to organize the Department of Vertebrate Paleontology at the American Museum of Natural History acting as it’s first curator. Osborn's close association with American Museum continued for over 45 years, and included a long tenure as its President, 1908-1933. During these years the museum's collections expanded enormously and it became one of the preeminent research institutions for natural history in the world.

Osborn is noted for describing and naming both Tyrannosaurus rex and Albertosaurus in 1905, Pentaceratops in 1923, and Velociraptor in 1924. One of Osborn's favorite groups for study was the brontotheres, and he was the first to carry out comprehensive research on them. He also wrote an influential textbook, The Age of Mammals (1910).

Apart from his own research, Osborn is perhaps best remembered for the sponsorship of the five immensely successful Central Asiatic Expeditions during the 1920's and 30's led by Roy Chapman Andrews.

Entry from HERE and HERE.

Rethinking Archaeopteryx Flight

Structure and function of hindlimb feathers in Archaeopteryx lithographica. 2006. Nick Longrich. Paleobiology 32: 417–431.


Artistic rendering of Archaeopteryx © Nick Longrich

From the Quirks & Quarks web page:

When Archaeopteryx was first discovered, it quickly became one of the most important fossils ever found. With the skeleton of a dinosaur and the feathers of a bird, it provided the first solid link between the two groups of animals. Today, the line from dinosaurs to birds is well accepted, but it doesn't mean the skeletons don't have secrets still to be revealed. Nick Longrich, a PhD student at the University of Calgary, recently uncovered one of these secrets: that Archaeopteryx had flight feathers on its back legs. This changes our picture of how these birds flew, although exactly how the back legs were involved in flight isn't clear. It does suggest, however, that birds probably developed flight coming down from the trees, rather than by jumping into the air.

I missed this when it came out so I’m getting caught up now…

Here’s the link to the Quirks & Quarks page with an audio link to Nick’s interview, or click HERE to go directly to the MP3 interview.

Visit Nick’s excellent page on Archaeopteryx and his research HERE

Evolution of Genome in Near-Real Time

Comparative genome sequencing of Escherichia coli allows observation of bacterial evolution on a laboratory timescale. 2006. C. D. Herring et al. Nature Genetics, published online: 5 November 2006

"Paleontologists look at the fossil record to study how evolution of dinosaurs and other animals occurred over millions of years, but in the case of the E. coli bacterium, new technology has given us the ability to observe evolution as it is occurring over a matter of days," said Bernhard Ø. Palsson, professor of bioengineering at UCSD. "The published genomic sequences of bacteria are like a fossil record and our experiments confirm that these genomes can change quickly as bacteria adapt to new conditions."

Palsson's team used comparative genome sequencing technology to identify evolutionary changes that occurred during the experiment in the bacterium's complete set of genes.

The researchers report that they grew E. coli in an environment that favored the emergence of mutants: the organism was fed a poorly metabolized carbon and energy source called glycerol.

After six days of growth, mutations appeared in the gene for an enzyme that initiates the process of enzymatically breaking down glycerol. Cells with mutations in the so-called glycerol kinase gene grew 20 to 60 percent faster than those without the mutation.

"This straightforward approach to the study of experimental evolution can be used as a tool for discovery and analysis, and could even be used to discover bacterial capabilities that would benefit humankind in a variety of ways," said Herring.

Darwin In The Gobi

Another stamp sheet that I picked up in Ulaanbaatar. Click the image to enlarge.

New Elasmosaur Found In Montana

Our old buddy and fellow U Calgary grad makes the news!

Pat Druckenmiller, in the collection room of MSU's Museum of the Rockies, displays the skull and lower jaw of an ancient sea monster found in central Montana. (MSU photo by Jay Thane).

From the press release:

Ken Olson of Lewistown and his son, Garrett, found the fossils in mid-August about 75 miles northeast of Lewistown. Since Horner was in Mongolia, Olson said he prepared the fossils himself and delivered them to Horner about three weeks later. Olson, a retired Lutheran pastor, has long collected fossils for the museum. Two of his best finds are the large Torosaurus skulls displayed there.

"It's a very important specimen," MSU paleontologist Jack Horner said at the Museum of the Rockies where the fossil rests in boxes. "We have been looking for it for a long, long time."

Believed to be approximately 70 million years old, its skull and lower jaw represent the first complete skull of a long-necked plesiosaur found in Montana, according to Montana State University experts. The skull is said to be one of the best specimens of its kind in North America.


A long-necked elasmosaur. (Illo courtesy of Dr. Druckenmiller).

"This critter is one of the long, ridiculously long-necked plesiosaurs," said Pat Druckenmiller, an MSU expert in marine reptile fossils. Druckenmiller, who described a new plesiosaur called Edgarosaurus from southern Montana in 2002, was part of a Norwegian expedition in August that mapped the location of several giant fossils in the Arctic. He is now an adjunct instructor in the Department of Earth Sciences at MSU.

"If the skull is 40 cm long, the neck could be seven to 10 times that length," he said.

"This is basically the first good elasmosaur (long-necked plesiosaur) skull found in Montana," Druckenmiller said. "That, of course, is really neat. In fact, I would say this is one of the top five skulls of an elasmosaur in North America."

Ebay Dino Posters

Atomic Surgery points out that www.emovieposter.com has a lot of dinosaur and related movie posters up for auction this week.

Dinosaur Park Bites The Dust

Wairarapa, New Zealand is set to lose a $30 million dinosaur theme park originally planned for the Martinborough countryside. Dinosaurs Rock owner Jackie Bush said interest is very strong from another council "further up the North Island" and they will take the park where there is most support.

In July, Dinosaurs Rock announced the "world-class" park would be situated just outside Martinborough with life-sized dinosaurs created by the special effects supremos at Weta workshop. Weta workshop will still create the dinosaurs, but now Dinosaurs Rock, owned jointly by Mrs Bush and her husband Darren, is in the early stages of talks with another council. Link

Thanks to the Digital Dream Machine Blog for the head’s up on this.

Flamingo Oddity

Cephalic vascular anatomy in flamingos (Phoenicopterus ruber) based on novel vascular injection and computed tomographic imaging analyses. 2006. Casey M. Holliday, Ryan C. Ridgely, Amy M. Balanoff, Lawrence M. Witmer. The Anatomical Record 288A: 1031-1041

With their spindly legs, long necks and bright plumage, flamingos are a curiosity of nature. Now a new discovery by a team of Ohio University researchers reveals an anatomical oddity that helps flamingos eat: erectile tissue.

From the Ohio U press release:

Flamingos are known for their peculiar feeding behavior. While standing in shallow water, they bend their necks, tilt their bills upside down in the water and swish their heads from side-to-side. Their large tongue acts like a piston, sucking water into the front of the bill and then pushing it out the sides. Fringed plates on the tongue trap algae and crustaceans in the circulating water.

“The flamingos’ feeding habits have captured people’s curiosity for ages, but that wasn’t the original focus of our research,” said Casey Holliday, who recently earned a doctorate in biological sciences from Ohio University and served as lead author on the study. “We were investigating the evolution of jaw muscles in lizards, birds and dinosaurs. By sheer luck we discovered something new about flamingos.”

A 3-D view of the bird’s head was created using a new computed tomography (CT) scanning technique developed by the Ohio U team that highlights blood vessel anatomy. The researchers noticed large oval masses of erectile tissue located on the floor of the mouth on either side of the tongue.

“No one ever anticipated finding something like this, and now we’re scratching our heads trying to understand the role these tissues play,” said Lawrence Witmer, a professor of anatomy in Ohio U’s College of Osteopathic Medicine who directed the study.

Larry has this to add, "The project was done as part of a routine vascular injection study to provide information that feeds into several of our fossil archosaur projects. It also has other paleo tie-ins because we found osteological correlates that might inform us about evolution of similar structure in other animals."

Click HERE to go to the Witmer Lab’s “Vascular Anatomy In Flamingos” page for more information and some cool CT animation video.

Readers up in Canada will be able to see a piece next week on “Daily Planet” (Discovery Channel Canada) all about this story.

New Phylum Discovered; Brains Paraphyletic?

Deuterostome phylogeny reveals monophyletic chordates and the new phylum Xenoturbellida. 2006. Sarah J. Bourlat et al. Nature 444 85-88.

Genetic analysis of an obscure, worm-like creature retrieved from the depths of the North Atlantic has led to the discovery of a new phylum.

From the U Florida press release:

Scientists have long been puzzled by the half-inch-long Xenoturbella first retrieved from the Baltic Sea more than 50 years ago. Early genetic research identified it as a type of mollusk but more precise genomic sequencing showed that Xenoturbella belongs to its own phylum.

It is one of only about 32 such phyla in the animal kingdom. "During the last 50 to 60 years, only a few new phyla have been established," Moroz said.

Perhaps more significant, the analysis of Xenoturbella seems to confirm that human beings and other chordates share a common ancestor. Its extreme characteristics suggest that this common ancestor – one the creature shares with its sister phyla, echinoderms and hemichordates, as well as chordates -- did not have a brain or central nervous system.

A reconstructed genetic record reported in the article also implies that the brain might have been independently evolved more than twice in different animal lineages, Moroz said. This conclusion sharply contrasts the widely accepted view that the centralized brain has a single origin.

SVP 2006 Photos

Do you recognize these characters? I do!

The photos were taken by ReBecca Hunt who has a large assortment of pictures from the 2006 Society of Vertebrate Paleontology conference in Ottawa up at www.dinochick.com. Go check 'em out now!

The Elephant's Missing Link

A pig-sized, tusked creature that roamed the earth some 27 million years ago represents a missing link between the oldest known relatives of elephants and the more recent group from which modern elephants descended.

The teeth of the newly described Eritreum melakeghebrekristosi.

From the U of Michigan press release:

The group's findings, to be published this week in the Proceedings of the National Academy of Sciences, suggest that mastodons and the ancestors of elephants originated in Africa, in contrast to mammals such as rhinos, giraffes and antelopes, which had their origins in Europe and Asia and migrated into Africa. The dating of the new fossil, discovered in the East African country of Eritrea, also pushes the origins of elephants and mastodons five million years farther into the past than previous records, said Martin Sanders, lead author.


Image Link

After 25 million years ago, larger proboscideans such as mastodons and gomphotheres—the ancestors of modern elephants—dominated the scene. Elephant-sized, with long tusks and trunks, these advanced proboscidans had more complex teeth that emerged more slowly, so that each quadrant of the mouth had only one or two functional teeth in place at a time.

"The new fossil from Eritrea is important because it shows aspects of dental anatomy in common with the advanced group, including molars with more cusps and complex crowns and the delayed maturation and emergence of molars," said Sanders. But the new fossil also has characteristics in common with palaeomastodonts, namely smaller body size and a jaw structure that suggests shorter tusks and trunk.

Whay Are There More Species In The Tropics?

Evolutionary and Ecological Causes of the Latitudinal Diversity Gradient in Hylid Frogs: Treefrog Trees Unearth the Roots of High Tropical Diversity. 2006. John J. Wiens et al. The American Naturalist 168: 579-596.

From thr U Chicago press release:

In a paper appearing in the November issue of The American Naturalist, John Wiens and a group of researchers have shown that, contrary to expectations, species seem to evolve at similar rates in tropical and temperate regions. What causes the difference in species numbers between tropical and temperate regions is not something special about the tropics that leads to more rapid speciation, but rather that the temperate areas were colonized more recently, leaving less time for species to originate and accumulate in these regions.

The researchers studied the causes of high tropical species richness in treefrogs in the Americas. Combining analyses of evolutionary trees based on DNA sequences with GIS-based methods for analyzing the effects of climate on species distributions, the researchers found no relationship between how quickly species originate within a group and whether that group is tropical or temperate.

However, they did find a strong relationship between when each region was colonized and the number of species there today. Thus, the high species richness of tropical regions seems to be explained by the ancient origin of many groups in the tropics, more recent colonization of temperate regions, and by the inability of most tropical species to tolerate the variable temperatures of temperate areas. Image Link

5 Million Year Old Retrovirus Reanimated

A team of scientists has reconstructed the DNA sequence of a 5-million-year-old retrovirus and shown that it is able to produce infectious particles.

From the press release:

The retrovirus--named Phoenix--is the ancestor of a large family of mobile DNA elements, some of which may play a role in cancer. The study, which is the first to generate an infectious retrovirus from a mobile element in the human genome, is considered a breakthrough for the field of retrovirus research. The findings are reported in Genome Research.

"Phoenix became frozen in time after it integrated into the human genome about 5 million years ago," explains Dr. Thierry Heidmann, lead investigator on the project. "In our study, we've recovered this ancestral state and shown that it has the potential for infectivity."

Retroviruses, whose genomes consist of RNA, can create DNA "copies" of the RNA genomes and incorporate them into the genomes of their hosts. Phoenix belongs to a sub-category of retroviruses--known as HERVs (human endogenous retroviruses)--which inserted copies into the human germline millions of years ago. Remnants of HERVs now comprise nearly 8% of the human genome, but most were rendered inactive long ago by mutations.

Mongolian Stamps

Here are some Mongolian stamp sheets I picked up last summer. Click on each image to enlarge.




Those are Triceratops? Quite a wacky combination of dinos.

Cave Bear Claw Marks

The bear that left a 3-foot-long claw mark in an Ice Age clay bank was the largest bear species ever to walk the Earth, about 6 feet tall at the shoulder and capable of moving its 1,800 pounds up to 45 mph in a snarling dash for prey.

Art © Frank Frazetta from HERE.

From the Cleveland Plain Dealer:

The claw mark by the extinct giant short-faced bear still looks fresh today in a southwest Missouri cave that some scientists are calling a national treasure - an Ice Age time capsule sealed for thousands of years.

Riverbluff Cave, discovered accidentally five years ago on the outskirts of Springfield, is slowly yielding its fossil treasures as a small team of scientists and volunteers gingerly explores it while trying to preserve a rich bed of remains, from bones to tracks and dung.

"Remains in the cave date back at least 830,000 years and possibly over 1 million years. At some point at least 55,000 years ago, it was sealed by rocks and mud until a construction crew blasted a hole in one end while building a road on Sept. 11, 2001.

Fossil Footprints Found In Mexico

A trail of 13 fossilized footprints running through a valley in a desert in northern Mexico could be among the oldest in the Americas, Mexican archeologists said.

From Yahoo! News:

The footprints were made by hunter gatherers who are believed to have lived thousands of years ago in the Coahuila valley (photo) of Cuatro Cienegas, 190 miles (306 kms) south of Eagle Pass, Texas, said archaeologist Yuri de la Rosa Gutierrez of Mexico's National Institute of Anthropology and History.

"We believe (the footprints) are between 10,000 and 15,000 years old," De la Rosa said. "We have evidence of the presence of hunter gatherers in the Coahuila desert more than 10,000 years ago."

The oldest discovered footprints in the Western hemisphere are in Chile, and are believed to be 13,000 years old. There 6,000-year old footprints in the U.S. state of California, in Brazil and in Nicaragua.

The age of the Mexican footprints is dwarfed by those found in Africa. The oldest known hominid foot marks are in Laetoli, in Tanzania, and are believed to have been made 3.5 million years ago.
Photo from Reuters

See Jane. See Jane Come to Cleveland Pt. 1

Last Wednesday, David Chapman, the CMNH Casting Technician, and I drove up to Beamsville, Ontario to pick up the ‘Jane’ mount that Research Casting International (RCI) produced for us. The CMNH acquired this mount through an exchange of cast material with the Burpee Museum who have the original skeleton.

Jane will go on display with Sue the T. rex from the Field Museum when that touring exhibit opens up at the CMNH Nov. 11, 2006. After that Jane will find a permanent place among our museum’s displays.


Photo © M. Ryan
To bring back our new dinosaur we rented a 17ft. U-haul van. Alas, this was not the one we took but ours did have an illo of some giant mushrooms reminiscent of the scene in the 1960 Version of The Lost World.


Photo © M. Ryan
Here’s a shot of part of their work area. That’s a bronze T. rex in the background and our unpainted Jane mount is in the lower left.


Photo © M. Ryan
David Chapman checks out another Jane mount that RCI was building they day we arrived.


Photo © M. Ryan
A close up of the bronze T. rex skull for comparison.


Photo © M. Ryan
Another shot of the bronze T. rex mount.


Photo © M. Ryan
Jane gets loaded in the van.


Photo © M. Ryan
Outside of the RCI building is a cast of the AMNH’s ‘Turtle Stone’.


Photo © M. Ryan
Another side of the stone.

See Jane. See Jane Come to Cleveland Pt.2

Our Wednesday started at 7:30am at the CMNH and David Chapman and I arrived back and unloaded the dinosaur about 9:30pm that evening. Aside from the problem caused by the Loading Dock being higher than the floor of the van, the two of us managed to get the mount out and into the loading bay in about 30 min. The next day we moved the mount (four ‘easy’ to assemble pieces) into the museum’s Kahn Hall where we (the VP and Exhibits Depts.) set it up the next day.


Photo © M. Ryan
That's VP volunteer Nicole helping David wheel the legs into the hall.


Photo © M. Ryan
Bolting the legs to their base.


Photo © Liz Russell/CMNH
Wiggling the body assembly into place. This was the only piece that gave us any real problems. That’s Arky Webber (top left), Gary Jackson, Nicole, Carl and me wrestling with the body rod.


Photo © Liz Russell/CMNH
Carl Jara gives the body assembly a shot of lube to help slide it into place.


Photo © M. Ryan
Half finished!


Photo © M. Ryan
Carl, Steve Green (long time VP volunteer) and David Chapman add the tail to the mount.


Photo © Liz Russell/CMNH
Nichole gets the honor of putting the head on.


Photo © Liz Russell/CMNH
All done!


Photo © M. Ryan
What’s the final mount look like? Well, I’ll hold that photo back until the show opens. Here’s a picture of the mount back in RCI before it was painted.

So, what is Jane? The Burpee Museum refers to it as a juvenile T. rex but there has been a lot of discussion about whether it is a Nanotyrannus (CMNH has the holotype) or whether Nanotyrannus is actually a T. rex. Mike Henderson of the Burpee is convinced of Jane’s status as T. rex, but his research has not been completed or published so for now the CMNH will be calling the mount a ‘juvenile tyrannosaur’.

Lucy Not Coming To the Smithsonian

The famous fossil of Lucy is scheduled to tour the United States, but one place it won't be on display is the Smithsonian's National Museum of Natural History.

From Yahoo! News:

"Not only is it not going to come to the Smithsonian Natural History Museum, it is our position that we don't think it should leave Ethiopia," museum spokesman Randall Kremer said Wednesday.

Smithsonian scientists feel certain objects, such as Lucy, are too valuable to travel and should remain in their homes, he said.

In announcing the plans to display the artifact, Ethiopian officials had listed Washington as a stop on Lucy's tour, though they didn't specify where in Washington the skeleton would go. The tour arrangements are being made by the Houston Museum of Natural Science and not all locations have been finalized.

The fossilized remains were discovered in 1974 in the remote, desert-like Afar region in northeastern Ethiopia. Lucy is classified as an Australopithecus afarensis, which lived in Africa between about 4 million and 3 million years ago, and is the earliest known hominid.

Most scientists believe afarensis stood upright and walked on two feet, but they argue about whether it had ape-like agility in trees. The loss of that ability would suggest crossing a threshold toward a more human existence.
Image Link.