STL Science Center

STL Science Center

31 December 2015

Special Bird

(C) Lia Booysen
As everyone the world over celebrates the New Year (in the Julian calendar anyway), a few people want to see some things about Aepyornis. I think that David Attenborough and the BBC have taken care of how popular this bird is. If that was not enough to prove its popularity, look at the admiration still held by the people of Madagascar for the giant birds. World mythology sometimes attributes the myth of the Roc, a giant bird of prey, to the eggs of Aepyornis as well as the idea that it may have only been a baby for an even larger bird; ratites remain quite juvenile in appearance in many ways. These birds even provided inspiration for an H. G. Wells short story: Aepyornis Island. Please read the short story and enjoy the interpretative artwork from Lia Booysen related to the story. Their appearance in video games, while not entirely novel, also attests to their popularity. I certainly like the look of these birds in Zoo Tycoon 2 myself, though subsequent public modifications have made them appear less "majestic".

30 December 2015

Extinction Hypotheses

Happy Madagascan children with an Aepyornis egg, (C) Madagascar-tribune
There are many hypotheses as to how Aepyornis went extinct. Many of those hypotheses center on human interaction because post-settlement by what we would now consider the indigenous people (those are the Malagasy people, a healthy melting pot of groups from places like Borneo and southeastern Africa). Considering that Madagascar was the last large landmass on the planet to be settled by humans, the wildlife had a very good long run of evolving with little to no human disturbance; evidence exists for foraging groups spending short periods of time on the island prior to permanent settlement. The question with Aepyornis becomes what kind of human interaction could have caused a 400 kg bird to go extinct? Hunting seems to be a natural answer to that question, but the bird was so enormous that a sustained "farming" of the bird would have been able to feed the population of the entire island quite well for an extended period without causing the extinction of the birds. This may have been the neither goal of the population nor within their scope of worry. However, consider the implications of a "farmable" 400 kg bird and how that might change holiday dinners! Another possibility was the hunting of the young or unborn birds. Due to their size it is unlikely that Aepyornis ever laid large clutches of eggs; extant ratites are capable of laying a small amount of eggs in each breeding season but are considerably smaller. As each egg was large enough to feed multiple people it is feasible to assume that they were taken entire nests at a time, allowing for either multiple meals or a village sized egg feast. Assuming communal nesting sites, the breeding season for these birds alone could have sustained the island and more. This path to extinction is straightforward of course; the ingestion of one's offspring eventually leads to the downfall of one's population and subsequent eradication of the species over time. The third hypothesis is concerned with a combination of the other two hypotheses coupled with habitat loss as a major factor in the extinction of the birds.

29 December 2015

Papers for Eggs

Aepyornis papers, as with many aspects of the history that has been documented about these birds, are mostly about eggs. Constituting the most readily available fossil evidence of the birds, these eggs are easily studied because of their abundance. Not all of these egg papers are really about the eggs though. They have to be more specific than many studies because studies that simply describe eggs only really need to be done once. However, describing the calcite orientation in one study and isotope chemistry of the shell in another. Despite a lesser abundance of skeletal remains studies of estimated weight have been published as well. A combination of studying the eggs and the skeleton of Aepyornis culminated, at least once, in a great study of the osteology of embryos that were preserved with eggs. Because we have embryos as well as adults we have a strong line of ontogenetic evidence concerning the bird. Having a great deal of studies from egg to adult is great for any extinct animal and we are extremely lucky to have this much for this animal.

28 December 2015

Young Attenborough

Yesterday's BBC television clips were, when put together, a great short documentary definitely worthy of movie Monday. Instead of searching for a great deal of new documentaries, and there are not all that many that exist, I have decided to share a pair of videos that show just how much David Attenborough loves Aepyornis. There are many reasons that Attenborough has discussed this bird in documentaries decades apart, but he really must have some love for the birds as it has been reported that he kept one of those fossil eggs he had rebuilt while in Madagascar and, as far as the story goes, still has it some 54 years later. In the Zoo Quest to Madagascar show that these come from he also searches for lemurs and other Madagascan animals. However, the important thing is that David Attenborough discusses an egg and shows just how large those eggs were. Also of note is the fact that locals know of egg fragments despite the birds being extinct for a significant amount of time.



27 December 2015

Average Facts, Giant Bird

Elephant Birds appear to be quite popular on the internet. About, Encyclopedia Brittanica, and the BBC all weigh in concisely and with some good images of the bird in question. Many other independent sites also have fact sheets, paragraphs, and even short but detailed descriptions of Aepyornis. The real wealth of Elephant Bird information may be in the short clips below:

On the disappearance of Aepyornis:

On the height of Aepyornis:

On the egg of Aepyornis:

On the extinction of Aepyornis:

26 December 2015

Forgetting Feathers

Image courtesy of Museon; Den Haag, Nederland
Instead of looking at different feather patterns in different illustrations of Aepyornis the art for Saturday focuses much more on the morphological characteristics of the Elephant Birds. A bird weighing as much as a Polar Bear is an interesting animal no matter what shape it may be presented in. However, Aepyornis is shaped in a very familiar way to other large terrestrial birds; not surprisingly Aepyornis looks very much like other ratites, especially ostriches. Like ostriches, Elephant Birds possess large feet that are mostly held flat on the ground and atrophied wings. The wings are not entirely absent from the giant birds, but at almost 3 m (10 ft) tall, the wings would not be of much use in getting off the ground unless they were significantly larger than they are. The large feet compensate by providing significant thrust and allowing the bird to move briskly along the ground. Aepyornis possessed legs far too robust to be as gracile as other ratites and an ostrich or an emu could easily outpace the large bird despite having slightly shorter legs. Instead, the Elephant Bird was much more likely to use its legs like those of cassowaries; kicking another animal with force and standing their ground would be more likely occurrences than outrunning predators. A 3 m bird would not have many predators, especially on Madagascar, once full grown. However, like most ratites, it also would not likely have been a predator, even though it could have easily been an apex predator on Madagascar. There were other birds that may have taken on that duty in their stead.

25 December 2015

Christmas Dinner

I skipped yesterday's post because we know most of the reasons that Gastornis is popular and it felt as though it was a post that did not need to be made. Regardless, Happy Christmas (if that is your thing) and Happy Holidays of various other sorts that exist.

This week will be the final fossil bird week to close out the year. I had contemplated discussing one of the oldest extant species of birds, the Magpie Goose (Anseranas semipalmata), but decided to be entirely fossil oriented to close out the bird topic. The fossil bird this week is the genus Aepyornis, a group of extinct ratites endemic to Madagascar. Known colloquially as Elephant Birds, the genus consisted of four species (A. gracilis Monnier 1913; A. hildebrandti Burckhardt 1893; A. maximus I. Geoffroy Saint-Hilaire 1851; and A. medius Milne-Edwards and Grandidier 1866) and is touted as the heaviest group of birds to have ever lived. The largest, A. maximus, is known to have weighed up to 400 kg (880 lbs). This is a known number because Elephant Birds have only been extinct for approximately 1000 years. Being a ratite, and weighing 400 kg, Aepyornis species were not capable of flight, no matter how much they may have wanted to escape Madagascar. Ratites tend to look vaguely like chicks throughout ontogeny, and such "youthful" appearances may have caused early explorers to assume that Aepyornis was not fully grown, even at 400 kilograms. However, use of the name Elephant Bird by many, including Marco Polo, may have actually referenced raptors living on or near Madagascar more than the giant ratites. Despite a confused nomenclature, Elephant Birds are enormous recently extinct ratites, like Moas, that went extinct partially because of human interaction (i.e. hunting). Considering an Aepyornis egg was large enough to feed a small family hunting the animals to extinction does not seem very far-fetched at all.
Left to right: Aepyornis maximus, Struthio camelus, Homo sapiens

23 December 2015

More Anatomy

Compiled by Adam Pritchard and Matt Borths of the Past Time podcast
This week we have discussed the legs, feeding apparatus and likely diet, and general familial history of Gastornis. One of the only other anatomical features we have not discussed in detail are the wings of this animal I noted before that the wings appear to be more developed than those of the true terror birds. This lends itself to a more well developed keeled sternum that is often associated with flight muscles. These muscles appear to be weakly developed in Gastornis; however, their existence and the development of the keeled sternum, regardless of how slight that keeling is, allow some insight into the evolutionary position of Gastornis in Anseriformes in relation to the capability of flight within the family. There is a reason that ducks and geese are high fat, heavily muscled birds; that in turn has led to their inclusion in our diet. Ducks and geese have low aspect wing ratios and less than desirable aerodynamically shaped bodies. They tend to be a little rotund, but most herbivorous animals are as they require more gut to process vegetation. Gastornis was also probably a fairly rotund bird as it would have also required significantly more digestive tract than the carnivorous contemporary birds around them. Gastornis was not flying though, so the fact that its family tree members have a lot of muscle to power themselves through the air definitely influenced its keeled sternum and possibly causing Gastornis to also have enormous muscles in the chest. One conclusion we can draw from this is that Anseriformes were flying both before and after the terrestrially confined Gastornis was running around the forests of the northern hemisphere.

22 December 2015

Use It To Crunch Seeds

Evidence has mounted that Gastornis was not a carnivore a great deal since it was originally covered in this blog. Back in 2012 when we originally discussed the diet of the giant bird and share all kinds of illustrations and clips from the Walking With series, meat was the only thing considered to be on the menu for Gastornis. Since that time biomechanical studies from earlier have been countered by evidence from chemical analyses that show that the diets of these birds were most likely highlighted by vegetable matter. When we look at the beak both possibilities obviously make sense. The Witmer and Rose biomechanical study asserted that the beak was strong enough to break bones and certainly to kill small animals like Eohippus. They are not incorrect and the implications that they made regarding diet are logical, especially for a bird that appears to be extremely convergent with South American terror birds. However, that power could have also been used to break open tough seeds and their meat inside. The large beak appears to have been mostly flattened in the oral cavity (the roof of the oral cavity or the ventral shelf of the premaxilla and maxilla), which is good for crushing, but not entirely ideal for breaking seeds open in the most efficient manner. What could be more efficient for this purpose may be considered coincidental or may have been lost in fossilization. The anatomical character that we are considering here could be a ridge or sharp edge to the beak that was keratinized for added strength. Assuming that this was not lost and may not have existed (I have not seen the fossils first hand and cannot therefore assert to its existence or loss) another option to make the breaking open of seeds more efficient, is occlusion of the upper beak that we have discussed many times with the lower beak or mandible (dentary, splenial, angular, and surangular). This occlusion can be seen, but is minimal between the beak and mandibles. It can be assumed from these bones that the keratin ramphotheca covering the beak would not have occluded differently, but we cannot say that they did not have sharp edges capable of shearing seeds. Given all of the papers and anatomical evidence, it seems that we could consider Gastornis more of a terror to seeds, than other animals.

21 December 2015

The Proposed Diet

Many reasons exist as to why the giant Anseriform Gastornis is hypothesized to have eaten many little horses daily, or weekly. Chief among these reasons is, of course, that the enormous solid and akinetic bill of Gastornis was a perfectly suitable weapon for concussing or otherwise subduing the earliest forms of horses. When we say early horses or small horses we are talking about the dog-sized (think somewhere between beagle and cocker spaniel if that helps) Eohippus that was still able to navigate the forests and enclosed areas of the Eocene. Later horses could not manage forests as well due to their larger sizes. Eohippus was still hypothesized to have a small amount, at least, of speed associated with its locomotion. Gastornis' slower speed led to the hypothesis that the giant bird was an ambush predator, surprising the small horses and using its solid beak as a sledgehammer to know the horses down and disabling them. There are representations of this all over the internet. The most notable and memorable is probably the one that the most people have seen. View the hunt below and bear in mind that this is a reasonable hypothesis for this bill, but there may be another viable hypothesis which we will attempt to explore tomorrow, granted that there are enough papers to discuss diet well. The strangest thing about this video is actually that the killing stroke has been edited out a bit.

20 December 2015

Giant Facts, Giant Bird

The revelation from yesterday that Gastornis is an enormous duck should have sunk in quite well by now. If it has not, here are some interesting facts about that giant duck. The first fact pages come from the BBC which chose Gastornis as a key figure in the Walking With Prehistoric Beasts series that appeared after the dinosaur series. That version of Gastornis was well done; however, they did imply that the hatchet-like movement of the beak was basically the same mechanism used by other large birds that lived, rather than noting the lack of a known hook on the premaxilla. The page hosted by Dinosaur Jungle does not worry about this hook-and-hatchet conundrum and instead simply discusses the facts that are know about Gastornis. Intriguingly, the image used on the page makes Gastornis look much more like a giant walking eagle and a great deal less like a duck relative; we do not expect it to look like a duck exactly, despite how much we have mentioned that it is related to ducks and geese. Of perhaps the most interest today, is an entry in Brian Switek's National Geographic blog Laelaps which introduces the idea that the bill of Gastornis was constructed for a more herbivorous diet than a fleshy diet. I must highly recommend reading this as an introduction to the topic of diet that we will discuss in the next couple of days. The last time Gastornis appeared in this blog we accepted the predatory role, and it was mentioned heavily in yesterday's entry also, but we will explore other uses of the morphology of the bill that we have been very actively discussing this weekend so far.

19 December 2015

Well Known Birds

Gastornis with Titanis inset
The terror birds of the northern hemisphere are not all terror birds in their own right. The term terror bird is usually used in reference to the group of birds belonging to the family Phorusrhacidae, to which Gastornis does not belong. The family of Gastornis is actually Gastornithidae, but the order is Anseriformes, meaning that Gastornis is in fact a giant duck (or goose if you like those better). The order of the true terror birds is Cariamiformes, a group that includes the extant Seriemas; predatory South American terrestrial birds much like the African Secretary Bird. What all of this means is that the lineage of Gastornis evolved to look, act, and dominate its landscape convergently rather than as an offshoot genus of the true terror birds. This convergent evolution is seen throughout the anatomy of the bird (the fossil anatomy that we can look at that is of course). The true terror birds, represented by Titanis, have a hooked, stout bill consisting of the premaxilla and maxilla. The bill is highly akinetic and was likely used as a hatchet-like weapon in prey acquisition. The bills of Gastornis were also highly akinetic and composed of the premaxilla and maxilla. However, they lack the premaxillary hook seen in terror birds and, while they may have also been used as a hatchet-like weapon, the lack of a hook means that the bill could not be used to pierce prey. Instead the bill would have acted more as a hammer, bludgeoning prey. The synsacrum (fused sacral and sometimes lumbar vertebrae) of Gastornis was longer than that of the Titanis; however, this does not mean that Gastornis was more agile or that it used this elongated tail to run with better balance. The legs of Gastornis are actually more robust and less likely to have allowed for bursts of speed than the agile but powerful lower limbs of Titanis. These traits lead to the hypothesis that Gastornis may have been an ambush predator rather than an actively stalking and chasing predator. Gastornis also possessed traits that are reminiscent of their closest relatives in that it had fully formed, but reduced and weakened, wings and a sternum that was mostly flat. An extremely reduced ridge is somewhat present in the midline that is homologous to the fully keeled sternum of flying Anseriformes. Titanis and other Phorusrhacids have an absent keeling of the sternum or a completely flat (rounded as encloses the thorax) sternum.

18 December 2015

Previously Viewed Gaston's Bird

From a paper by Matthew, W. D.,  Granger, W.,and
Stein, W. 1917.
Once in the not too recent past we discussed what is basically a giant terror turkey of the northern hemisphere. Discovered in Europe and described under the name Gastornis by Hebert at the same time (a pair of decades later) as it was discovered in North America and described as Diatryma by E. D. Cope and Barornis by O. C. Marsh. Diatryma and Barornis, being named 21 and 49 years after Gastornis respectively, have fallen to the level of junior synonym. However, regardless of the level at which these particular species may reside in hierarchical taxonomy, the discovery of multiple members of the genus on multiple continents is of great importance to understanding how "in charge" birds were in the early Cenozoic. Enormous birds were clearly the apex predators of South America, and likely much of Australasia as well with potential large predatory birds spreading to Africa as well. Gastornis is known only from Europe, Asia, and North America, but the fact that apex predators in northern and southern hemispheres both were avian is astounding. Gastornis consists of 3 - 4 species from Europe (G. parisiensis H├ębert, 1855;G. sarasini Schaub, 1929;G. geiselensis Fischer, 1978; and G. russeli Martin 1992), a minimally known Chinese species (G. xichuanensis Hou, 1980), and the extremely (comparatively) well known North American species (G. gigantea Cope, 1876).

17 December 2015

Sometimes It Is

Popularity because of popularity sounds funny, but it is a theme that has been addressed here many times before. Perhaps too many time in fact. The fact with fossil animals, though, is that sometimes they are famous just for being famous. The penguins discussed this week fall into that exact category as nothing makes them exceptionally famous except that they are well known for being giant fossil penguins. To anatomists and ornithologists they are amazing specimens of the early radiation and specialization of the penguin family. They are testaments to the anatomical organization of penguins in that they provide us with a first indication of anatomy that is still readily employed by extant penguins; adaptations that have changed little in 36 million years are obviously well situated to working in the role and environments in which they are employed. Regardless of how they are touted, both of these animals were indeed kings of the water in their day, in the bird world. They remain important and amazing in our view today.

16 December 2015

Fossil Collections

Icadyptes montage. A) Icadyptes and a Humboldt penguin (D. Ksepka);
B) Wings of (L-R) Short-tailed Shearwater, Waimanu, Icadyptes, Emperor Penguin
(Ksepka and  Ando 2011); C) Illustrator's interpretation of Icadyptes
The collected fossils of both Inkayacu and Icadyptes are fairly similar, as we would expect with contemporaneous and similarly sized penguins. What exists, however, to tell them apart from one another? The answer, as in any fossil animal, is in the bones. No one knows these fossil penguins better than Daniel Ksepka, now with the Bruce Museum in Greenwich, CT and it is thanks to his tireless study and description of both taxa that we know the key characters of each animal. He had help now and again and the description of Inkayacu was spearheaded by the University of Texas, overall, but much of what has been written about penguins in the past decade or so has been written by Ksepka and his collaborators. In the case of Inkayacu some of the evidence of difference from Icadyptes is actually found in the feathers of the animal. The precise imprints that were made in both the matrix material around the bones is so well preserved that the shapes and sizes of the pigment containing melanosomes has been preserved as well as the shape and size of the contour feathers that covered the body below the flight feathers. An important note of distinction ought to be mentioned here for the less avian-inclined. Despite not flying in the traditional sense, the feathers of the wing that are used in locomotion in penguins are considered flight feathers as they still perform the same role and the style of swimming of penguins is very much like a submarine flight. What is very interesting about the bones of Icadyptes shown here is their fairly obvious resemblance to those of other fossil penguins (Waimanu tuatahi) and extant penguins here represented by an Emperor Penguin (Aptenodytes forsteri). The flipper of Inkayacu is absent some elements, but it also very close in resemblance to extant and other fossil penguins. The skulls are morphologically similar as well, but the flippers are more important in showing that penguins were highly specialized as long ago as these 36 million year old animals. The skull shape had developed multiple times in other waterbirds, making their convergent shape less important for defining what makes a penguin.

From Clarke, et al. 2008
References:

15 December 2015

Black and White Print, Not Feathers

The most important thing to remember about these fossil penguins is that they are very much like modern penguins. That fact born in mind, reading the papers detailing studies of these penguins makes the papers easier to feel okay about. Not understanding that these penguins are like modern penguins in many regards make the papers seem very odd, as they discuss the animals in ways that make them seem quite modern in respect to the "oddness" of other fossil animals in comparison to their extant descendants. After reading the papers this logic makes sense, I promise. Those papers detail the evolutionary history of penguins as well as detailing individual aspects of both penguins. Those include osteology and the colors of feathers. Fossil feathers and coloration is a fantastic topic actually, and I definitely recommend reading that last paper on Inkayacu.
From Clarke, et al. 2010.

14 December 2015

Penguins in History

Yesterday I shared videos for both Inkayacu and Icadyptes. Somehow, despite the fact that penguins are probably the neatest flightless birds, there are not more stories and videos devoted to these two ancient penguins. It is both sad and great that we do not really need a video concerning these two penguins directly to know how they fed, their mode of locomotion, or what they looked like. The two penguins were both penguin-like in appearance and most likely swam the same way that extant modern penguins swim. The feeding done while swimming, of course, was probably also similar if not identical. The depth at which that feeding was done in each genus was probably much different though. Due to the fact that extant penguins provide a good hypothetical proxy for these fossil penguins, please enjoy this wonderful ballet of penguins swimming, doing dopey things, and generally being penguins.

13 December 2015

Penguin Facts

Sharing facts for two animals today is best done in a list format. Therefore, please attend to the following lists!

Inkayacu:
About: http://dinosaurs.about.com/od/prehistoricbirds/p/Inkayacu.htm
Interview with Dr. Julia Clarke:


Icadyptes:
About: http://dinosaurs.about.com/od/prehistoricbirds/p/giant-penguin.htm
Animal A Day: http://animaladay.blogspot.com/2012/11/icadyptes-salasi.html
Dr. Rodolfo Salas showing fossils and an interview with Dr. Mario Urbina:

12 December 2015

Penguins Competing for Space

Icadyptes; (C) Nobu Tamura
The two fossil penguins Inkayacu and Icadyptes were actually quite different despite living in similar areas and having similar ecologies.The pigments of the feathers of the penguins have been identified, tentatively but with few caveats, and this allows us to differentiate between the animals when feather impressions and melanosomes are present to identify the colors of the feathers. Icadyptes is similar to extant king and emperor penguins as far as we can tell in plumage. They appear to have had a few areas of yellow and black feathering but were mostly covered in white feathers Darker back feathers make deeper diving a realistic ecological impact on the way of life of Icadyptes. The darker black would allow for the penguins to be camouflaged from above when at deeper depths and their white feathers would have added to their camouflage from below as they would have blended in better with the lighter water nearer the surface. Drawing these conclusions we can say that it is likely that Icadyptes dove deeper than Inkayacu to feed. Sharks and contemporary mammals (I cannot seem to find an evolutionary appearance of Leopard Seals, but we can assume that they would have loved giant penguins given how much they love extant penguins) of the deeper waters would have preyed upon the penguins, making that camouflage necessary. Inkayacu, on the other hand, has been hypothesized to have been a brown to rusty red color below and black or a dark grey above. Again, the black or dark grey color would camouflage the penguins against the deeper waters, but the rusty color would not provide much camouflage against many backdrops. This line of evidence is used to argue that Inkayacu
Unattributed
is a shallow swimming penguin; there are melanosome related reasons as to why this is a possibility, but we can leave these at rest for the time being. At the moment, simply appreciate that there are two colorations hypothesized for the two penguins and that each color scheme denotes attributes of each species. The two disparate ecological niches would mean that the two penguins could live in the same area and feed on different prey without destroying the food sources of one another. It is an interesting system with two interesting and differently colored taxa represented.

11 December 2015

Dueling Penguins

Icadyptes (top) and Inkayacu (bottom)
I have decided this week that we really need to look at two animals at the same time. Distinctly different but interesting and similar, the two giant penguins of South America, Icadyptes salasi and Inkayacu paracasensis were both approximately 1.5 m (5 ft) tall and were amazingly developed 36 million years ago such that they resemble modern penguins in shape and function from their bills to their feathers. The fact that they were enormous and built for swimming, like their descendants, means that the ocean ballet we see with the much smaller modern penguins was happening 36 million years ago with birds as tall as an adult human (using myself as scale because I am short). As now, these penguins ate fish while they darted about in the ocean and, with their larger bodies and heads, were definitely capable of grabbing larger fish than current penguins. Assuming that fish were also somewhat larger in their time that is. We know that even now some adult fish can reach astounding size, but do not always because of commercial fishing. Human over-fishing did not cause the demise of these penguins, however. Due to the fact that the two penguins were discovered in Late Eocene rocks of Peru, they must have been contemporaries and should be considered together to discuss the ecology of each as they would have interacted in life.

10 December 2015

How Does One Become Famous?

The greatest toys I have seen (toys always relate to popularity in, I am sure, some mathematical way) of Jeholornis are actually quite interesting in their own right. These range from stuffed animals (see below) to styrofoam flyers to full on sculpture. I have to admit that the sculpture is amazing. There is a great deal of painstaking detail in that piece and I am quite impressed with it; I would own it if I could and I had a place for it. Jeholornis has occupied our imaginations and entertained our fancies about the origin of birds, and that is probably, in part, why it is such a popular early bird. The fact that it is an early bird has a lot to do with its popularity in the realm of paleontology. There is even a book (dedicated to all Jehol fossils really) that deals extensively with little dino-bird. It may be worth picking up, but as with any scientific book, it is difficult to find for a reasonable price.


09 December 2015

Forgotten Yesterday

(C) Matt Martyniuk
I lost track of time yesterday and have to backdate this post. That is all well and good though on the internet. The first anatomical thing worth mentioning about Jeholornis is the long tail. The tail of this small bird is very dinosaur-like in its anatomy. It is a long slender tail that appears to have been covered in small(ish) feathers down the length of the appendage. The end of the tail is covered in fan shaped brush like set of retrices that look something like a cat-tail (the plant not the mammal) in silhouette. Long tails like this are not unheard of in the bird world as birds such as magpies often have long tails that are as much for display as they are for controlling flight. Perhaps the reason for this long tail was for display, but it could have also been used to steer an otherwise somewhat unwieldy bird through the air during powered flight. Barring that, and assuming that Jeholornis was a good flyer, it may be the simplest explanation and the tail may have been for display purposes only.

The claws on the wings of Jeholornis are also of great interest. One of the age old questions surrounding birds is when did the hands change such that they no longer ended in claws, but only phalanges supporting feathers? As more and more fossil birds come to light the timeline of clawlessness becomes slightly clearer. It may not ever be definitively known when clawed wings gave way completely to feather only wings, but it would be interesting to discover. The claws of Jeholornis are fairly small and appear almost as an afterthought of development, but even this appearance does not make the phylogeny of clawed wings distinctly clearer. Regardless, Jeholornis is a small bird that still resembles a dinosaur in many ways and has, through a bit of luck, been preserved in significant numbers in the fine sediments of the Hebei Province.

08 December 2015

Slabs for Writing

The preservation of exquisitely fragile animals like birds (and pterosaurs, silly flying animals) is usually done with such fine sediments that the fossils are often found and removed as slabs of material. After those slabs are opened there is typically a slab, holding the actual fossil, and a counterslab that holds an impression of the fossil; this is where our wonderful feather impressions are most often found, though they have been known to come from the slab containing the fossil as well. Many of the remains of Jeholornis that have been procured, and certainly the ones that have been described, are found in this kind of arrangement. This is the reason also that so many of those papers are wonderfully descriptive and have such beautiful, for a crushed fossil bird, images of the fossil remains that are being described at the time. These include comparison papers between birds (Archaeopteryx vs. Jeholornis) as well as the straight descriptions of Jeholornis.

07 December 2015

Using up the Documentaries

Yesterday I shared a video that was probably the best video that is easy to get to online featuring Jeholornis; it was a clip from Dinosaur Train which may make it seem a little sad. However, there is also a hybrid edited video that an internet denizen put together on Jeholornis. It may actually feature another animal in some parts of it, but that is okay, as it is done fairly well and shows a very similar animal if nothing else. Watch it and let us know what you think about it:
The animal that comes from the BBC clips is undoubtedly a different early/near bird, but I cannot place it for one reason or another and it would be wonderful to get a memory boost!

06 December 2015

Too Much Fame

Jeholornis is so well known in the public domain that finding simple fact files or short essays describing the small primitive bird is actually quite difficult. The problem is that there are just too many links online. Some of the quick and simple pages that stand out right away come from About and the Encyclopedia of Life. The article from the EoL is not much edited from the original Wikipedia article, but it is still worth reading. Jeholornis has even shown up everywhere in videos, meaning that we can look to videos as well to learn about this bird. There are not any that I recommend above others, but there is a good episode of Dinosaur Train in which Jeholornis features prominently. I would certainly recommend watching it with the little paleontologists in your life today! You can find that video at this link.

05 December 2015

Flying and Chasing

(C) Emily Willoughby
Jeholornis is hypothesized to have been a seed eating bird with a long tail and claws on its wings. The long tail and the claws on the wings are more than a hypothesis, of course, as they are present on many of the slab fossils that have been described and published. The other 93 plus unpublished specimens could have wonderful claws and tails, but we may not know for a very long time. The nicest fossils are published on first, which we should expect, and those beautiful fossils have painted a wonderful picture of an active little early bird. As stated at the start of this entry, the hypothesized diet of Jeholornis included seeds with a potential ability to ingest the leaves of plants like gingko themselves. In this image our favorite little bird (for this week) is actively eating gingko leaves off a small branch. Not knowing that that plant was gingko, it may also appear as though this Jeholornis is staring down the dragonflies on the tree it is standing near. Regardless, the long tail with its short caudal retrices and the claws on its wings are well represented here. The images of these traits could be slightly different depending on the illustrator, but I chose this image because I think it does a great job of representing the anatomy.

04 December 2015

Long Tails and Little Teeth

The bird from Jehol, a region in China (now Hebei Province), was turkey sized and capable of powered flight. Despite having teeth Jeholornis had a diet consisting of mostly seeds. Their long tails, however, were used for flight, and were therefore much more bird-like than their teeth. Regardless, the main attraction of Jeholornis was neither its long tail nor its mouth that contained small teeth. Their claim to fame was is their clear flight abilities and the fact that that powered flight was achieved with well preserved feathers. Those feathers are asymmetrical, an important adaptation in powered flight.The other important characteristic associated with Jeholornis is the shear number of specimens and the variety that may (only seven have been described) be preserved in those specimens is a very intriguing and important for the history of birds. This week's bird is also quite beautiful, as far as delicate bird fossils go.
From O'Connor, et al. 2013

03 December 2015

Like an Ostrich of Doom

Whenever a bird is popular, or any fossil animal for that matter, it is always fun to look at extant birds to see what kind of similarities there are in the two popular taxa. Terror birds in general are most reminiscent of ostriches and other ratites. What we really care about on Thursday is the popularity of the animal and whether or not there is evidence of that popularity out in the wide world. We know, with the television, improvised cards for games like YuGi-oh, and even the creation of video game characters (we have not seen a good Spore creature in a while). Titanis is a very popular bird and, being the only terror bird from North America, it is quite unique. Also, look at this hypothetical baby, he is adorable:

02 December 2015

Strange Ideas

There was a hypothesis once that Titanis, and other Phorusrhacids, may have had a theropod-like claws at the end of their wings. This hypothesis came to light because the writs was considered to be extremely rigid and supposedly lacked the ability to fold against the body like a traditional wing. However, extant "terror birds", the seriemas of South America, do not possess a clawed manus at the end of their wings despite a largely unchanged wing and wrist. In fact, looking at a seriema is in a way looking at a scaled down, though no less vicious, version of their ancestors of the past. These living birds possess short wings and elect to fly-hop when they do leave the ground, which is rare. The idea that Titanis may have had wings weak enough to restrict flight but strong enough to allow for fly-hopping to slightly higher structures makes the speedy predator slightly more frightening as it adds a vertical component to its domain. Aside from obstacle avoidance, such an ability would have probably been most useful in nesting habits and, though its weight would have likely been too much for a typical branch, the bird could have built enormous nests that required fly-hopping to gain the apex of. The idea of a bird that large flying even an insignificant distance vertically is nearly preposterous though, and in all likelihood Titanis never left the ground on purpose. Regardless, the North American terror bird was more than capable of inflicting damage on prey items without clawed hands or the ability to chase other animals into trees.

01 December 2015

Titanic Research

A great deal of research has been conducted regarding Titanis walleri over the years. The bird's body has been discussed many times over for many different reasons, but mostly for descriptions of the known skeleton and its relationship to other Phorusrhacids. Beyond descriptions many have studied the age of the birds and their genus. Some of the most cursory treatments of the bird are actually references in papers on the "Great American Interchange" that occurred when South American and North America came into contact with one another for the first time.