Friday, January 27, 2012

Phlegethontia.

Phlegethontia is a snake-like amphibian that lived from the Carboniferous to the Permian period. It lived in swamps and probably, unlike most snakes today, spent most of its time swimming in water, like a frog or a newt. Phlegethontia was about one meter long and it ate small animals and insects.


Phlegethontia was found in the Mazon Creek, in Illinois, among other places. The skull had holes in it, and this made it light. My hypothesis is that Phlegethontia evolved this way because a lighter skull would be easier to lift, and therefore it would be easier for Phlegethontia to snatch a flying insect from the air, much like this adaptation makes it easy for a snake to strike quickly. The skull of Phlegethontia is similar to that of a snake.




Phlegethontia looked very much like a snake, suggesting a similar lifestyle, except more in the water than on land. Amphibians like Phlegethontia cannot permanently live on land without getting wet because they would dry out and die.

At one time there was something called Dolichosoma longissima. But this was an incorrect description and paleontologists realized that it was actually a member of the genus Phlegethontia. Now it is called Phlegethontia longissima.




References:

http://en.wikipedia.org/wiki/Phlegethontia

http://dinosaurs.about.com/od/tetrapodsandamphibians/p/phlegethontia.htm

Wednesday, January 18, 2012

Siphusauctum.

Siphusauctum is a newly discovered animal from the Burgess Shale. It is one of the weirdest animals from the Burgess Shale ever found. Siphusauctum was described by Jean-Bernard Caron, Curator of Invertebrate Paleontology at the Royal Ontario Museum, and Lorna J. O'Brien from the Department of Ecology and Evolutionary Biology at the University of Toronto, and was just announced.

One of the most obvious things about Siphusauctum is how enigmatic it is. It looked like a ctenophore on a stalk. Some scientists believe that it is related to the mysterious Dinomischus. Siphusauctum and Dinomischus both have a stem and a round calyx, but they are actually very different. Dinomischus's calyx is more like a flower than a ctenophore.

© Marianne Collins

Siphusauctum had a two-layered stem and a holdfast at one end, which was probably used to anchor it to the sea floor. It presumably could draw its holdfast into the stem and move along the sea floor to find a new place to anchor itself.

Siphusauctum had a very simple gut, which was just a tube with a round part at the end, which was the stomach. It just sucked in water along with tiny creatures and plants, which were its food.

The size range for Siphusauctum is 19 mm to 223 mm. There are variable sizes for stems, holdfasts, and calyxes on different individuals of the species. One thing that stands out about it are the comb rows on its calyx, which resemble those of ctenophores. Although the two are unrelated, Siphusauctum has noticeable similarities with the ctenophores.


Siphusauctum are sometimes found in large clusters, suggesting that the animal lived in groups, like the possibly related Herpetogaster, also from the Burgess Shale. Its species name is S. gregarium because it was gregarious, meaning it lived in groups. Siphusauctum also resembles some crinoids, except crinoids had tentacles and Siphusauctum did not.



References:

http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0029233

http://news.utoronto.ca/university-torontoroyal-ontario-museum-scientists-discover-unusual-tulip-creature

Tuesday, January 17, 2012

Protopriapulites.

Protopriapulites (pro-toe-pry-uh-pew-LITE-ees) was a priapulid worm that I think looked more like a peanut than a worm. It was about one centimeter long. Some fossils showing the gut full of mud indicate that Protopriapulites may have fed on detritus from the sea floor in the same way that the spiny Burgess Shale worm Fieldia did.

© Life Before the Dinosaurs 2012

Protopriapulites is known from the Chengjiang in China. It had a ball-shaped posterior, a head similar to that of Ottoia, and a proboscis similar to that of Fieldia. I believe that the ball-shaped posterior of Protopriapulites may have helped anchor it in its burrow, and if a predator tried to grab its head, it would not be able to pull the worm out of its burrow. So the predator would probably be discouraged and look for something else to eat. 

Protopriapulites was noticeably similar to Paleopriapulites, another peanut-shaped worm from the Chengjiang, except Protopriapulites had a spiral gut and Paleopriapulites did not.

Protopriapulites is a common species of priapulid worm in the Chengjiang.

Image from Fossil Mall

Protopriapulites is mentioned in the book The Cambrian Fossils of Chengjiang, China, which I received from Kamakanui, one of my readers. It is an amazing book mentioning some of the weirdest animals in the Chenjiang. It also has many obscure creatures which are hard to find on the internet, such as Protopriapulites. There is a whole section full of the enigmas of the Chengjiang, such as Facivermis. Each section has a certain phylum that the creatures mentioned in it belong to, in this case Protopriapulites would be listed under "priapulida." This book has tons of information on all these mysterious and obscure creatures.





References:

The Cambrian Fossils of Chengjiang, China: The Flowering of Early Animal Life, Blackwell Publishing, pg. 66 & 67.


http://www.fossilmall.com/EDCOPE_Enterprises/Chengjiang/chengjiangfossils91/chengjiangfossils-91.htm

Saturday, January 14, 2012

Helicoprion (Part 2).

I've already posted Helicoprion before on my blog, as my very first post. But I have learned so much since then that I would like to write about some new information.

Helicoprion had a buzzsaw-shaped tooth whorl on its lower jaw, which is what it's famous for. The most up-to-date reconstruction suggests it being a shark-like fish with a long upper jaw and a long lower jaw. At the end of the lower jaw was where the tooth whorl was.

© Life Before the Dinosaurs 2012

Although it is sometimes reconstructed eating ammonites, the absence of broken teeth on most specimens of its tooth whorl suggests that instead of eating ammonites, it fed on animals such as squid, fish, and other animals without shells. 

Although most specimens of Helicoprion's tooth whorl are about 10 inches in diameter, one specimen has a diameter of about 2 feet, suggesting that this odd shark-like cartilaginous fish might have grown more than 32 feet long, which makes Helicoprion one of the largest cartilaginous fish of all time. Only Megaladon, which didn't appear until the Tertiary period, was larger.

© Shark Trust
Fossils of Helicoprion have been found all over the world, as far apart as Australia and North America. The first remains were found in Russia and were named Helicoprion bessonovi. Other fossils of Helicoprion bessonovi have been found in China, which is not surprising to me because they were nearby. At the time that Helicoprion lived, all the continents were together, which probably explains why it has been found in so many places. In the United States, fossils of Helicoprion are found mostly in the western states, near where fossils of the related Edestus have been found. 


Helicoprion lived from the Carboniferous to the Triassic, which is quite a long time for a single genus to be around.

© Oleg Lebedev 2009


References:

http://www.wired.com/wiredscience/2011/03/unraveling-the-nature-of-the-whorl-toothed-shark/

http://www.paleospot.com/galerie_rubrique.php?rub=2 (lots of amazing illustrations of prehistoric sharks)

http://gsa.confex.com/gsa/2011RM/finalprogram/abstract_187593.htm

http://en.wikipedia.org/wiki/Helicoprion

Monday, January 9, 2012

Helmetia.

Helmetia was an unusual trilobite-like arthropod with eyes on the bottom of its head, and a broad, flat body. Having eyes on the bottom of its head would have blinded it if it crawled across the ocean floor, and its broad, flat body would have been buoyant and made it hard for Helmetia to get down to the sea floor in the first place, just like something flat will not sink in quicksand. Helmetia could reach lengths of about 19 cm, which was quite large for a Cambrian animal.

© SMITHSONIAN INSTITUTION – NATIONAL MUSEUM OF NATURAL HISTORY. PHOTO: JEAN-BERNARD CARON

Helmetia is obviously well-armored and large, so it probably didn't have too many predators. Large anomalocarids were the only animals big enough to even try to eat Helmetia. Helmetia had hard spines on the edges of its armor and its flat shape also would have made it hard for an anomalocarid to grip it. All its armor probably would have made Helmetia a slow swimmer, but this probably did not make it vulnerable.


Helmetia was presumably a filter feeder, feeding on plankton, bacteria, and other microscopic living things that floated around in the water column.


Fossils of Helmetia are extremely rare. They have been found in the Burgess Shale and were discovered by Charles Doolittle Walcott.

© Life Before the Dinosaurs 2012


References:

http://www.trilobites.info/triloclass.htm

http://burgess-shale.rom.on.ca/en/fossil-gallery/view-species.php?id=65&m=4&&ref=i#description

Monday, January 2, 2012

Field Museum birthday trip. [Update: goal reached!]

Many thanks to PZ Myers for supporting the cause. Art has already received many generous contributions for his trip to Chicago to see the Field Museum. Thanks to everybody who supports his work on this blog.

If you click the "ChipIn" button here or in the right margin, you can help fund the trip! The ChipIn widget takes a while to update, so contributions don't show up right away. They will, though. They will!

Update! Art has raised 100% of the funds needed to help him get to the Field Museum for his eighth birthday. 100%! Thanks to PZ Myers and everybody who chipped in. You people are the best!

Odaraia.

Odaraia (oh-duh-RAY-uh) was a bizarre-looking creature that has been found only in the Burgess Shale. Charles Doolittle Walcott described this animal in 1912. The species name is Odaria alata, which is the only known species, except for a possible member of the genus from the Chengjiang in China, Odaraia? eurypetala. Although Odaraia  may have had four eyes, this is still disputed because the other two eyes on the fossils may have been something else.


Odaraia was first described as a crustacean, although it is now believed to have been a stem group arthropod. Odaraia presumably lived by swimming upside down in the water column as it searched for prey, which it sifted out of the water with its legs and ate. One of its most notable features was its three tail fins, which helped it stabilize in the water.


Odaraia had a large carapace that covered a fair amount of its body, including its legs. This meant that it would be impossible for Odaraia to walk on the bottom of the ocean, but it would be easy for it to swim.


References:

The Cambrian Fossils of Chengjiang, China: The Flowering of Early Animal Life, Blackwell Publishing, pg. 142. Many thanks to LBtD fan Kamakanui for this generous gift!

http://burgess-shale.rom.on.ca/en/fossil-gallery/view-species.php?id=89&ref=i&

http://en.wikipedia.org/wiki/Odaraia