Basal theropod phylogeny

•October 6, 2007 • Leave a Comment

The base of the theropod tree has been shaky despite major advances in understanding avian origins and the evolution of coelurosaurs. A part of the problem has been the poor Triassic and early Jurassic record of the theropods. A key to unlocking the phylogeny of early theropods was a spectacular find from the Early Jurassic fossil beds of Antartica, Cryolophosaurus. Finally, a long needed osteological study of Cryolophosaurus was conducted by ND Smith et al which offers and extraordinary view of theropod evolution. The early phylogenetics studies of theropods hinted suggested that there were two major clades within them the ceratosaurs and the tetanurans. Further, staurikosaurids and Eoraptor were considered basal-most clades of theropods. But this has been questioned over the years with newer analysis of the “ceratosaurs” and the discovery of new fossils like the well-preserved Zupaysaurus from South America and the fragmentary Dracovenator from South Africa. The new analysis by Smith et al incorporates data from Cryolophosaurus and improves the picture vastly.

In a nutshell it makes the following points:
Eoraptor and the staurikosaurids are basal saurischians rather than theropods.
– The basal-most theropod clade is a coelophysoid clade comprised of forms like Liliensternus, Coelophysis, Syntarsus and Segisaurus.
Zupaysaurus is a sister group of all other remain theropod groups.
-Of the remaining theropods the basal-most clade is the dilophosaurid clade formed by Dilophosaurus, Dracovenator, Cryolophosaurus, and “Dilophosaurus” sinensis from the Lufeng formation.
-The next clade which forms a sister group of the tetanurans is the neoceratosaurid clade which includes within it Ceratosaurus, Elaphrosaurus and the abelisauroids.
-The basal-most tetanuran clade unifies the two south American forms Condorraptor and Piatnitzkysaurus.
-The major clades within tetanurae are: spinosauroids (including spinosaurids proper and Eustreptospondylus, Torvosaurus and Afrovenator); allosauroids (including sinraptorids, carcharodontosaurids and Megaraptor, which emerges as a carcharodontosaurid); coelurosauria.

Examining the Chandodarshana

•October 4, 2007 • Leave a Comment

We had earlier alluded to the Neo-vedic composition attributed daivarAta gajAnana sharma aka daivarAta, a student of the great Sanskrit poet kAvyakaNTha gaNapati shAstrI. A student of Sanskrit poetry will be definitely benefited by reading his masterly work on indrANI or umA devI, the umA-sahasraM, a 1000 verse composition in which each 25 verses are in different Chandas. Some of them bring out the wonders of dhvani in the classical meters. While I had heard of this neo-Vedic composition for long it took a while before I finally laid my hands on the Chandodarshana in nAgarI script along with its anvaya bhAShya to examine it.

shrI gaNapati curiously comments that at the time of the production of the Chandodarshana the young daivarAta was not particularly well-versed in saMskR^ita composition. He says these mantra-s came out of his mouth while he was meditating near the reNukAMbA temple and he [gaNapati muni] collected and recorded the full and clear ones. To me the whole piece seems to be gaNapati muni’s work with daivarAta apparently a mere instrument. He gives this away by cryptically alluding to his ancestor in the opening phrase “vasiShTho giraH” Now the big question is it really a simulation of vedic? Below are the conclusions of my analysis:
-svAra rules: largely follow R^ig vedic pattern, with kaMpa svarita-s and basic udAtta accents generally similar to their vedic counterparts.
-mythology and history: Very low mythological content compared to the real veda- vR^itra saMgrAma, vala, namuchi etc receive little attention. Vedic heroes like divodAsa athitigva, trasadasyu, sudAsa etc receive no mention.
-ritual: Limited references to ritual in general. References to the soma ritual are very few in comparison to the actual vedic corpus. The shrauta fire ritual too is minimally alluded to. Instead a ritual of drinking and offering pa~ncha gavya is presented. Ritual words : e.g. juhomi, havAmahe, yajAmahe are minimally used.
-devatA-s: marut-s, ashvinA and mitrAvaruNa have a relatively limited presence compared to the real veda. The devatA dvandva-s are also conspicuous by their absence or rarity. There is an enormous emphasis on sarasvati, way beyond what is seen in the RV – in fact she is the most hymned deity in this collection. viShNu is identified with the puruSha, something which is absent in the RV or the earlier vedic texts. sarasvatI is mainly hymned in her aspect as vAk rather than as the deity of the water cycle and rivers, which is the dominant theme in the RV. rudra’s wife is named as gaurI rather than pR^iShNi, which is the name in the RV. brahmaNaspati is prominently connected with sarasvati- something which is typical of later hindu thought rather than in the RV.
-influence of the nirukta: The nirukta scheme of ordering deities, and the terms and synonyms used by the nirukta play a dominant role in the refrains and organization of the hymns.
-language: While there are archaisms that resemble the vedic language rather than classical saMskR^ita, there are many features distinguishing it from the real RV language e.g. : use of classical dvandva i.e. ashvinau instead of RV ashvinA; use of the term puruSha throughout the corpus in the sense of person. puruSha is a late RV word coming to fore only in the maNDala 10 in the puruSha hymn; use of the particle IM (usually meaning “now” or “indeed” – like in ya IM shR^iNotyuktam) in an excess and implying its tAntric sense as a bIja of the devI. In essence, different layers of RV dialects are homogenized. Use of vyAhR^iti-s in RV-styled verse is again not typical of the original. vyAhR^itis are typical of yajushes.
-philosophy: several upaniShadic elements seem to dominate. e.g.: prANa-s being compared to marut-s, Atman, puruSha etc.

So in short Chandodarshana is a modern author’s emulation of the R^ig, conditioned by the subsequent interpretive tradition and developments. Nevertheless, it is one of those rare modern examples of vedic-styled poetry that bears many features of the original. It does illustrate gaNapati muni’s tremendous poetic abilities both in the classical and vedic realm — he would have truly been a R^iShi had he lived in the vedic period.

Philosophizing on magnetic sight

•October 1, 2007 • Leave a Comment

I wanted to document the great victory of the Hindu armies in the land of Karroo. After the memories of 1983 which are faint, almost going back to our infancy, this is the only time we have displayed any notable valor in battle with the two Rajput warriors on the helm putting to sword the Anglo-Saxons, the peerless pirates from down under, the Voortrekkers and finally the bloody-eyed al-ghazis. But then I was talking to people who make little sense of cricket. But R and I had a long talk that starting from Steve Irwin’s crocodiles, passed through a three part BBC documentary on reptiles, then through cryptochromes whose ancient origins we had nailed, and finally took a philosophical turn on to consciousness. I would have liked to capture the various elements of it, both scientific and philosophical, but for now just a few points for we are like the haunted man chased by a vetAla.

“vedA yo vInAm padam antarikSheNa patatAm |” (shunaHshepa Ajigarti in RV 1.25.7a)
[varuNa] knows the migratory path of the birds through the atmosphere

“sarvA vA iyaM vayobhyo naktaM dR^iShe dIpyate | tasmAd imAM vayAMsi naktaM nAdhy Asate | ya evaM vidvAn agniM chinute praty eva tiShTya abhi disho jayati |” TS 5.6.4
A
All this (earth) in the eyes of the birds shines at night, therefore at night birds do not rest here. He who knowing this piles a fire finds support, and conquers all the quarters.

How do the birds manage their great feats of navigation, which need no further dilation ? How do they manage to home so accurately?

I believe the main reason why we fail to understand this well is because we apparently lack the magnetic sense. We have sight so we recognize an eye when we see it another animal or for that matter even in an alga like Chlamydomonas. We smell and taste so we can recognize the chemoreception in other organisms, we hear and we feel various stimuli via skin and sense stretch thus we are able to recognize auditory and tactile receptors elsewhere in the living world. These senses tend to dominant our conscious experience. There are two other senses that are less obtrusive on the consciousness — being filtered out most of the time. One of them strongly impinges on the consciousness, when altered — the balance sense. The other one, proprioception, while apparently filtered out does seem to contribute to the sense of I, an important part of conscious experience. But when it comes to magnetic sense most of us do not know what that is, and hence lack that experience to easily recognize its receptors in other animals.

Yet we have come to realize over the ages that it is one of the primary forces behind avian migration and homing.
continued …

sarvatobhadra maNDala

•September 30, 2007 • Leave a Comment

The saiddhAntika-s and the kaumara-s

•September 24, 2007 • Leave a Comment

I was examining a kaumAra manual used by priests from Kilmangalam (a village near the town of Periyakulam) for the worship at the aruLmigu bAlAsubrahmaNya temple. The temple is itself was built around 1020 CE by one of the greatest Indian emperors, choLa rAjendra-I. The temple has an apocryphal legend associated with it: rAjendra was hunting boars and at this spot killed a boar sow which was feeding its piglets. He had a vision of kumAra feeding the orphaned piglets and keeping them alive. Struck by the vision rAjendra built a temple to honor kumAra. The kaumAra manual used by the Kilmangalam priests to conduct rituals at this temple is from the 1500s of CE composed by a certain hAlAsya. In its opening it has a salutation to great saiddhAntika tantriks of yore. It names durvAsa as the founder of the lineage and then lists the following historical tantriks:
1) sadyojyotis son of kheTaka 2) bR^ihaspati 3) nArAyaNakaNTha 4) his son rAmakaNTha-II 5) aghora-shiva deshika.

The South Indian Urdhvasrotas (saiddhAntika ) commentarial tradition remembers many great prior Acharya-s and siddha-s, but like its Kashmirian counterpart its memory starts with sadyojyotis and bR^ihaspati, both of whom are termed siddha-s. After this it shifts to the great Kashmirian lineage which opens with bhaTTa rAmakaNTha-I:
rAmakaNTha-I -> vidyAkaNTha-I -> nArAyaNakaNTha ->rAmakaNTha-II -> vidyAkaNTha-II and shrikaNTha (probably).

Then it remembers the Tantrik-s of the mattamayUra lineage and its great patron, the Rajput king bhoja, from northern and central India (outside of Kashmir): brahmashambhu, mahArAja bhojadeva paramAra, somashambhu and ishAna-shiva.

In south India itself it remembers the great Tantriks-s of the greater Tamil country like:
aghora-shiva, his student vaktra-shambhu, j~nAna-shiva and trilochana-shiva associated with Chidambaram and Mysore.

An even earlier lineage of saiddhAntika Tantrik teachers in the south is recorded in the inscriptions of the chAlukya king vikramAditya-I of bAdAmI. The rAja himself was initiated into the Urdhvasrotas mantras by sudarshanAchArya and his school included the shaiva brAhmaNa scholars: rudra-shiva, gAyatrI-shiva and parama-shiva. Similarly, the pallava king narasimhavarman-II also mentions attaining dIkSha into the saiddhAntika mantras in an inscription on the rAjasimheshvara temple in Kanchi (~700 CE), but we know little of his lineage beyond this. No scholarly works on the tantras from any these early South Indian lineages are currently known.

There is no evidence that the earlier saiddhAntika-s from the pallava and chAlukya courts contributed directly to the medieval siddhAnta tradition. The illustrious South Indian Acharya aghora-shiva deshika of Chidambaram carried out a major synthesis with the saiddhAntika tradition by unifying the ritual prescriptions of mahArAja bhoja and somashambhu, with the Kashmirian commentaries of bhaTTa nArAyaNakaNTha and bhaTTa rAmakaNTha on the core tantra-s of the Urdhvasrotas. It is fairly reliably known that aghorashiva was active around 1150 CE and he expresses tremendous veneration for his Kashmirian predecessors. This suggests that there was a new influx of the siddhAnta traditions from Kashmir and Malava (e.g. king bhoja’s work) to the Tamil country prior to aghora-shiva. After he wrote his synthetic paddhati this became the standard tradition in the Tamil country with the Kashmirian Acharya-s providing theoretical base. One notable late change was the subtle transformation of the saiddhanta tradition with vedantic elements by the smArta appayya dIkShita.

In the Kashmirian tradition bhaTTa vidyAkaNTha-II was a contemporary of abhinavagupta, while rAmakaNTha-I was possibly closer to utpaladeva or just before him. sadyojyotis and bR^ihaspati might have also been from Kashmir but we have little information about their lives. sadyojyotis was definitely pre-sha~nkara. In his polemics against advaitin-s he clearly attacks the pre-sha~nkara advaita like that of bhartR^i-prapa~ncha who expounds pariNati-vedAnta in his bR^ihadAraNyakopaniShad commentary. One can imagine how sha~nkara having transformed vedAnta into mAyAvAda must have retaliated against these shaiva-s and demolished them in the debates that are supposed to have occurred in Kashmir and other places. The fightback against the mAyAvAda form of advaita is seen only later amongst the saiddhAntika-s in the works of rAmakaNTha-II.

-The main works of sadyojyotis that survive are : 1) the triad of works comprising the commentary on the raurava-sutra-saMgraha, namely the bhoga-kArikA, mokSha-kArikA and paramokShanirAsa-kArikA: collectively the raurava-vR^itti. 2) The commentary on the svAyambhuva-sUtra saMgraha named svAyambhuva-vR^itti. 3) Two works on the nature of existence according to these two sUtra collections: tattva-saMgraha and the tattva-traya-nirNaya. 4) nareshvara-parIkShA- a polemical work laying the siddhAnta shaiva position in contradistinction to the AstIka darshana-s, earlier pAshupata shaiva-s and pA~ncharAtric vaiShNava.
-The siddhAnta Tantrik bR^ihaspati-s works are poorly known and are :1) the raurava vArtika on the raurava-sutra saMgraha and 2) the shiva-tanu.
-bhaTTa nArAyaNa-kaNTha wrote the once famous sharan-nishA that is supposed to have clarified the tattva saMgraha of sadyojyotis like the moon shining on an autumn night. This work is remembered in both Kashmirian and Tamil tradition but does not seem to survive. He also composed new commentaries on the mR^igendra tantra.
-His son rAmakaNTha-II not only commented on the works of sadyojyotis but also on the mata~NgapArameshvara tantra.
-aghora-shiva in Tamil Nad composed commentaries building precisely on the works of nArAyaNa-kaNTha and rAmakaNTha and appears to follow their conservative path. This is quite clear from his epitome of the siddhAnta worship presented in the 100 verse stotra known as the pa~nchAvarNa-stava. Similarly, his student vaktra-shambhu also from TN seems to build on nArAyaNa-kaNTha’s work on the mR^igendra.

rAmakaNTha-II makes an interesting statement in the beginning of his commentary on the mata~NgapArameshvara that the siddhAnta tantras have been interpreted according to the theories of the nyAya atomists, vedantins and kaula Tantriks. rAmakaNTha-II then seeks to restore what he calls the correct saiddhAntika interpretation as per the path originally laid by sadyojyotis. Even the non-siddhAnta trika-kaula tantrics like abhinavagupta and the shrIvidyA tantric jayaratha cite these siddhAnta tantra-s and use them as authoritative works. They also try to accommodate bR^ihaspati and sadyojyotis within their scholarly framework. This shows that the siddhAnta tantra (and other such Agamic scriptures) had an independent position of respect (even if not on par with the shruti). This was probably in no small part due the prominent role they played in the domain of sthApana (=temple establishment), prayoga (=goal-oriented tantric rites) and yoga. In general other streams of AstIka thought and nAstIkas too in a subversive sense sought seem to have a priori accepted the praxis and mantra-shAstra of these tantras, though within their own established contexts. Thus, well before appayya dIkShita there were multiple attempts to treat the siddhAnta tantra-s from the stand point of other AstIka theoretical frameworks, including non-siddhAnta tantric models, rather than the one preferred by the shaiva tantriks.

As we have seen above the works of vaktra-shambhu and aghora-shiva suggests that the medieval South Indian authorities returned to the conservative path of interpretation of the Kashmirian shaivas by adopting rAmAkaNTha and nArAyaNakaNTha as the standard. But what about their association with the kaumAra path? As we know the temple of aruLmigu bAlAsubrahmaNya was in place before aghora-shiva and kaumara temples were present in TN even before that. The kaumAra path in TN is a much earlier transmission from North India — it is possible that it was associated with the early pre-aghorashiva saiddhAntika-s like those associated with the earlier chAlukya and pallava kings. However, we have no evidence for that. In fact the chAlukyas, pallava-s and kadamba-s who began as feudatories of the pallava-s were kumara worshipers even before their kings started acquiring shaiva dIkSha. The kaumAra path also has no notable role in the siddhAnta works of Kashmirian lineage or that of bhoja. Hence, it becomes likely that the siddhAnta shaivas actually invaded the domain of the preexisting and took over their activities especially in the domain of sthApana and prAsAda utsava vidhi. In terms of the mantra-shAstra we clearly notice this imprint in the kaumAra tradition of TN — the pa~ncha brahma mantra (a very key aspect of saiddhAntika worship) has been exapted for kaumAra worship. The installation of tridents and spears (trishula/shakti sthApanaM) in kaumAra temples also follows a saiddhAntika model. However, much of the other rites relating to subrahmaNya yAga, and kumAra mantroddhAra follow the actual kaumAra tradition. This take over by saiddhAntika-s is not surprising given that they already possessed sthApana tantra-s for parivara devatA-s including kumAra. However, it should be noted that it is erroneous to believe that the kaumAra was an offshoot of the saiddhAntika stream.

The technically educated kaumAra-s are a vanishing group: they seem to be extinct in the North in Rajasthan (where again there was an association with the shaiva stream), and are present in small clusters in Tamil Nad, and the Kanada and Tulu countries (where a pristine secretive subrahmaNya maTHa lineage survives). Their texts have rarely been published if at all and most lie as unedited and in some cases lacunose manuscripts from these regions. We are one remnant of this path. We have too much of a personal connection with this deva, but we know not what the roguish deva has in store for us.

USA and the Islamic powers: Recent events

•September 23, 2007 • Leave a Comment

A number of news items are of some interest in terms of the manufacture of opinion, and the clash of civilizations between the Judaeo-Christian west and Islam.
Item 1: The visit of the Iranian president to the US and the Columbia university. It is very interesting to note how the American media is in frenzy over the recent antics of Ahmedinejad. Like any other true believer in the monotheistic prophetic cult Ahmedinejad is a threat to the world. But there are very many of them all over the world so is he really that special or dangerous to merit the excitement. Let us note the following facts:
1) Iran was not involved in 9/11
2) Iran was an arch enemy of the Taleban, the hosts of Osama and his gang.
3) Iran has not carried out a terrorist strike on US soil and the last major assault on the US interests was a long time ago using Hezbollah proxies (Of course they are fomenting trouble for the Americans in Iraq now, but it is the Americans who got into a hell-hole in the first because of the being taken for a ride by the Neo-cons).
4) Iran is actually too weak to be a direct threat to the US, if the rulers of the US exhibited common sense.

Yet they are making a big noise about Ahmedinejad yapping at Columbia University or visiting New York.

In contrast, Pervez Musharraf was invited to New York and treated as a guest of honor. He was invited to talk his nonsense at the same Columbia University and also Cornell University (On September 26, 2006), another famous school in New York. He was feted by the American rulers and media as a great ally of the US.

Note the following facts now:
1) Musharraf was the primary supporter of the Taleban and gave them the infra-structure to support al-Qaeda.
2) It was through his support that al-Qaeda carried out 9/11
3) He still hides Osama, Omar and their gang and is supporting the resurgence of the Taleban in Afghanistan.
4) He has been involved in clandestine nuclear proliferation with North Korea and was a patron of Xerox Khan.
5) Most major Islamic terrorist activities conducted against the US trace back to Pakistani sources which are all orchestrated by Musharraf.
6) While Ahmedinejad is an elected leader, Musharraf is a dictator who deposed an elected leader. Not that this matters much to the rest of the world, but US paints a picture of being the beacon of democracy furthering various democratic causes the world over.

The US media largely praised Musharraf and no one protested against his visit to the universities in any serious way.

As va~Nga paNDIta said, the discerning person knows why this is so, and how opinion is manufactured by the controllers of the American media contrary to the facts. But it still remains comical on one hand and tragic on the other to see the American people being fooled so thoroughly to lose their lives and tax money due the patently delusive propaganda that the Iran and Iraq posed threats to their lives. Even more annoying is that Hindus seemed to be taken on this ride too, to act contrary to their self-interests (vis-a-vis Mushy in particular).

*-*-*

Item 2: The recent events in Iraq have brought to fore the role of American private armies, such the mercenaries of Blackwater and the like. These armies of interest to the geopolitical observer. Some probing shows that a frequent, if not the only constituent, of these mercenary armies deployed by the US is the following kind of individual: A macho leukotestate male, fired by ideals of Hollywood gunmen-supermen on one side, and protestant Isaistic delusions on the other. In essence he is a crusader a mirror-image of the Mujahideen standing firm in the fight of the cross against the crescent. Secondly, since regular armies could always be blamed for crimes against humanity, it is useful to deploy these unaccountable warriors, especially when they are fired with Isaistic fervor. Now, the scale of these Isaistic mercenary armies is particular striking — the one currently in the news headed by a fanatic Isaistic military-trained chieftain is supposed to have 20,000 men with their own military base and assault aircraft. No sovereign nation will allow such private armies, unless they are supported by the rulers. But the important lesson for us to learn is the potential of such Isaistic armies to cause harm to us heathens. We already know very well how the “soft arm” of the leukosphere in the form of various Isaistic activists- evangelists, priests, NGOs etc operate with impunity in India converting Hindus and subverting the nation. These soft soldiers are very likely to be backed-up by these private Isaistic armies of “contractors”. I believe this is already in place with India, Nepal and Tibet being major targets and will only increase in the future as they become relatively jobless in Iraq.

This too va~Nga paNDita had foreseen but the Hindus sleep on.

Gregory Paul’s prescience

•September 22, 2007 • Leave a Comment

The previous snippets on related topics:
* The big and small of theropods
* Organ and Edwards on dinosaur genomes
* Microraptor as a biplane
* Jurapterxy- wrong inferences?
* Tyrannosaurs and morphological evolution in coelurosaurs
* The rise of tyrannosaurs
* Buitreraptor
* The adaptive radiation of avian and para-avian clades

Thermopolis Archaeopteryx

Gregory Paul, the artist and maverick paleontologist published a remarkable book in 1988 “The predatory dinosaurs of the world”. For its era it was a masterpiece of scientific art. At that point in time, other than Archaeopteryx, feathered dinosaur fossils were hardly known from the Mesozoic. But Paul restored his theropods with feathers. What was striking was that his dromaeosaur and oviraptorosaur representations might be as good as those made after the “Chinese revolution” from Liaoning. He also predicted the hyperextendible claw in Archaeopteryx, which was proved after the publication of the Thermopolis specimen in 2005. However, what was even more striking was the theory presented first in that book that the dromaeosaurs were actually secondarily flightless dinosaurs that had reverted to terrestriality from an ancestor that resembled a flighted form like Archaeopteryx. In a subsequent book, “The Dinosaurs of the Air”, another artistic masterpiece, Paul went on build the case for the possibility of secondary flightlessness in the dromaeosaur, troodontid, oviraptorosaur and therizinosaurid clades. However, Gregory Paul is not one who uses phylogenetic methods to construct evolutionary trees and lay out his theories in the framework of a phylogenetic tree. Instead he builds his case based on mechanistic and anatomical arguments. As a result dinosaur evolutionists have tended not to cite his work. This sad in a sense because I believe that phylogenetic frameworks are not only vindicating his prescience but also adding details that were not accessible to him.

The latest in this line of finds is that of the dromaeosaur Mahakala omnogovae from Mongolia reported by Turner et al. Also authors on the paper are two of the most noted American paleontologists of the modern era, Norell and Clarke (famous for numerous evolutionary studies on avian and non-avian dinosaurs). Mahakala is from the Djadokhta formation in Mongolia from the Campanian age (i.e. the second last epoch of the Cretaceous). The remains are relatively scrappy but covering a good part of the skeleton — a partial skull with brain case, sacrum, partial pelvis, several vertebra, femur, foot with sickle claw, and ulna. Despite its relatively young age it is clearly a primitive dromaeosaur showing that primitive members of this clade were around even in the penultimate epoch of the Cretaceous. Its size was estimated at around 70 cm.

A phylogenetic analysis of the avian-paravian clade including Mahakala produced striking results. The basal most division was into birds and deinonychosaurs. The birds have as their basal most branch Archaeopteryx and Shenzhouraptor uniting as a monophyletic lineage of primitive long-tailed toothed birds. The next most basal lineage of birds that are a sister group to all other birds are the Omnivoropterygids which include the extremely enigmatic oviraptorosaur-like Sapeornis and Omnivoropteryx. The deinonychosaurs split up into troodontids and dromaeosaurs. The basal-most lineage of troodontids are the Chinese forms Mei and Sinovenator, with a crown group formed of Byronosaurus, Saurornithoides and Troodon. The basal-most dromaeosaur is Mahakala with 3 major radiations including: 1) The unenlagines- Unenlagia (>Nequenraptor?), Buitreraptor, Rahonavis and Shanag. Of these, all except Shanag are from the Gondwanan fragments. 2) The Chinese radiation comprised of Microraptor, Graciliraptor and Sinornithosaurus. Bambiraptor might also belong to this clade, but the prudish paleontologists, due to some weird dispute regarding specimen ownership or something like that tend to ignore this magnificent specimen. 3) The velociraptorine clade comprised of Velociraptor, Deinonychus, Saurornitholestes, Tsaagan, Adasaurus, Dromeosaurus and the large Utahraptor and Achillobator.

This tree suggests that flighted forms were potentially present on all the 3 major clades- Aves, dromaeosaurids and troodontid. Amongst the deinonychosaurs, Rahonavis from the unenlagine clade was initially described as a bird and was definitely flighted. Microraptor from the basal “Chinese clade” is also definitely flighted with the potential “biplane morphology”. Among the troodontids Mei and Jingfengopteryx might have had limited flight capabilities. Using the tree, Turner et al also reconstruct the common ancestor of deinonychosauria as well as the paravian clade (aves+deinonychosauria+Scansoriopterygids) as being around 70 cm and ~700 g which is consistent with them being fliers. Turner et al do not include the enigmatic and poorly preserved scansoriopterygids, which could further destabilize their clades in different ways. There are other fragmentary forms like Pedopenna, which might unify with one of the known clades or form yet other poorly known lineages within paraves. It is more likely that actually the flighted ancestor amongst coelurosaurs goes back further in time as Paul suggested, including the oviraptorosaurs and therizinosaurs, and perhaps even the alvarezsaurids (initially believed to be birds).


Sapeornis

This proposal has an important implication (which is in line with Paul’s original suggestion): Could our current cladistic analysis be artificial grouping flighted forms together into a monophyletic aves merely because they retain several flight adaptations? Is it possible that just like Rahonavis moved inside dromaeosaurs, other lineages currently grouped inside aves might actually group with other coelurosaur groups. One immediate candidate for this Archaeopteryx itself. Could it be that it is actually close to the ancestor of the entire paravian clade. Being the earliest representative of the clade from the Tithonian epoch of the Jurassic it is well-placed to occupy this position. Another more unclear case is the omnivoropterygid clade within Aves. Both Sapeornis and Omnivoropteryx share a general cranial similarity with oviraptorosaurs, in which some semi-pygostylic forms like Nomingia have been described. Is it possible that these represent the early-branching flighted representatives of the oviraptorosaurid clade ? More fossils, if and when they become available, might resolve these issues.

More recently, in another paper Turner et al present the discovery of quill knobs on the ulna of Velociraptor, just as those reported in Rahonavis. This establishes beyond doubt that even the flightless larger forms retained their secondary feathers This also shows how flightless derived forms with unmodified clawed hands proceeded in directions other than that seen Patagopteryx or the Ratites. Flightlessness in the deinonychosaurs and possibly oviraptorosaurs was often accompanied by retention of the flight feathers of the arm suggesting that that the feathers had an adaptive value beyond flight. Many possibilities exist but limited volancy in juveniles, and wing-assisted incline running are the ones I favor most.

Whatever the case it is becoming increasingly clear that as Paul had suggested flight emerged much before the avian crown group amongst theropods and might have been repeatedly lost in the early stages of its evolution and coexisted with precursors and derivatives like wing-assisted incline running, gliding from trees, and biplane volancy. It also appears likely that feathers (or the homologous dino-down) evolved before flight, most possibly as the functional equivalent of mammalian hair. When did this dino-down first emerge in archosaurs? We know most likely this emerged after the crocodile line branched off, by the exact point of emergence is the big question still in need of an answer.

 
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