tag:blogger.com,1999:blog-3049195237412585561.post2971734119020781709..comments2023-11-07T12:07:59.585-08:00Comments on Pterosaurs to Birds: The bigger pictureUnknownnoreply@blogger.comBlogger16125tag:blogger.com,1999:blog-3049195237412585561.post-20972439798114358092016-09-25T07:55:33.435-07:002016-09-25T07:55:33.435-07:00http://www.nature.com/nature/journal/v459/n7249/ex...http://www.nature.com/nature/journal/v459/n7249/extref/nature08124-s1.pdfDr. Pterosaurhttps://www.blogger.com/profile/13137867768653523183noreply@blogger.comtag:blogger.com,1999:blog-3049195237412585561.post-60028870301416114392015-12-08T09:14:38.788-08:002015-12-08T09:14:38.788-08:00A good analysis of node based and stem based defin...A good analysis of node based and stem based definitions:<br />http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2989695/Dr. Pterosaurhttps://www.blogger.com/profile/13137867768653523183noreply@blogger.comtag:blogger.com,1999:blog-3049195237412585561.post-53564723349105192512015-12-08T06:57:40.592-08:002015-12-08T06:57:40.592-08:00Helpful information:
Node-based:
Pennaraptora is ...Helpful information:<br /><br />Node-based:<br />Pennaraptora is a clade defined as the most recent common ancestor of Oviraptor philoceratops, Deinonychus antirrhopus, and Passer domesticus (the house sparrow), and all descendants thereof, by Foth et al., 2014.[1] <br /><br />Stem-based:<br />The ancestral paravian is a hypothetical animal; the first common ancestor of birds, dromaeosaurids, and troodontids which was not also ancestral to oviraptorosaurs.<br /><br /><br /><br />A node-based definition could read: "the last common ancestor of A and B, and all descendants of that ancestor". Thus, the entire line below the junction of A and B does not belong to the clade to which the name with this definition refers.<br /><br />A branch-based definition, often called a stem-based definition, could read: "the first ancestor of A which is not also an ancestor of C, and all descendants of that ancestor". Thus, the entire line below the junction of A and B (other than the bottommost point) does belong to the clade to which the name with this definition refers.<br /><br /><br /><br />In biology, the most recent common ancestor (MRCA) of any set of organisms is the most recent individual from which all organisms in a group are directly descended.<br /><br />The term MRCA is usually used to describe a common ancestor of individuals within a species. It can also be used to describe a common ancestor between species. To avoid confusion, last common ancestor (LCA) or the equivalent term concestor is sometimes used in place of MRCA when discussing ancestry between species.<br /><br />Dr. Pterosaurhttps://www.blogger.com/profile/13137867768653523183noreply@blogger.comtag:blogger.com,1999:blog-3049195237412585561.post-19920114942434431652015-12-04T18:25:46.142-08:002015-12-04T18:25:46.142-08:00http://www.brooklyn.cuny.edu/bc/ahp/CLAS/CLAS.Clad...http://www.brooklyn.cuny.edu/bc/ahp/CLAS/CLAS.Clad.html<br />Evolutionary SystematicsDr. Pterosaurhttps://www.blogger.com/profile/13137867768653523183noreply@blogger.comtag:blogger.com,1999:blog-3049195237412585561.post-90865798840697910982015-12-04T16:09:15.448-08:002015-12-04T16:09:15.448-08:00Reference to I-II-II preferred by most dinosaur wo...Reference to I-II-II preferred by most dinosaur workers<br />A bizarre Jurassic maniraptoran from China with elongate ribbon-like feathers<br />Fucheng Zhang1, Zhonghe Zhou1, Xing Xu1, Xiaolin Wang1 & Corwin Sullivan1<br /><br />http://www.nature.com/articles/nature14423.epdf?referrer_access_token=aXP0rMThuriYuvLDytsEU9RgN0jAjWel9jnR3ZoTv0PSoBPtAJS-K6Ofmq0_6wDOhsGY0rj_zJ_eQ8W9B9wsxLSCf2nbgU8Z-z5IJJQdfB_oT5rHGSjgUyjywdd61kg7z3GhdN-kkEBzDhZufuyKopWSgg-qEOLwE4c30ePqEJaqrjmI76uW5HZhMvNHypY7KJVZOa4ZNNYps69ieswFrXO4wDINm3UKCLxElIB4H4o%3D&tracking_referrer=www.nature.com<br />Dr. Pterosaurhttps://www.blogger.com/profile/13137867768653523183noreply@blogger.comtag:blogger.com,1999:blog-3049195237412585561.post-20772199048436700702015-12-04T11:18:39.042-08:002015-12-04T11:18:39.042-08:00From 2009 study:
Scansoriopterygidae (grouped with...From 2009 study:<br />Scansoriopterygidae (grouped with Avialae for correspondence matrix construction) Dr. Pterosaurhttps://www.blogger.com/profile/13137867768653523183noreply@blogger.comtag:blogger.com,1999:blog-3049195237412585561.post-537744083935601252015-12-04T07:30:55.496-08:002015-12-04T07:30:55.496-08:00http://www.nature.com/articles/nature08124.epdf?re...http://www.nature.com/articles/nature08124.epdf?referrer_access_token=1LIOYM249T2ALXmHhUVXQtRgN0jAjWel9jnR3ZoTv0NAxxXDTxDgb7tt7vNCs5i7CDx_p1E8pIL0dPMGIw0CIZ1LRnUZIDT1a3FIDY_UW4FRwpODRDVwWg-KbK448VK63yIXiGAa_H8fA42yVK8TsNhr_ASjWKKTbM-PJCMVzpKKElR4FEstewHl9DZGaHr9&tracking_referrer=www.nature.com<br /><br />Based on this study, the most parsimonious alignment is for the four digits of ceratosaurs to be I-II-III-IV and the three (and sometimes four) digits of all Tetanurae to be II-III-IV(V). Accepting such a topological shift at the base of Tetanura requires that the positional homology of the three digits of tetanurans is II-III-IV(-V), as suggested by Wagner and Gauthier34. Because the four digits of ceratosaurs are therefore most parsimoniously interpreted as I-II-III-IV, the small lateral metacarpal ossification of Guanlong35, Sinraptor36, and Coelurus represents the re-ossification of metacarpal V after it is lost at the base of Ceratosauria. The poor phylogenetic resolution for basal tetanurans in our study precludes us from hypothesizing whether this re-ossification event occurred once or more than once in the evolution of Theropoda. Likewise, the fourth metacarpal, which is reduced in primitive theropods and bears an unknown number of phalanges in Ceratosauria, re-acquires at least three phalanges in Tetanurans.Dr. Pterosaurhttps://www.blogger.com/profile/13137867768653523183noreply@blogger.comtag:blogger.com,1999:blog-3049195237412585561.post-57406428418071460502015-11-28T07:47:52.692-08:002015-11-28T07:47:52.692-08:00http://www2.gwu.edu/~newsctr/newscenter/research/d...http://www2.gwu.edu/~newsctr/newscenter/research/dinosaur/clark.pdf<br /><br />This implies the reduction of digit I before the divergence of the Ceratosauria and the<br />Tetanurae, the appearance of some polleciform features in digit II and the acquisition of a novel<br />phalangeal formula (X-2-3-4-X) early in tetanuran evolution. Both modifications are partially<br />indicated by the manual morphologies of ceratosaurs and more basal theropods. Also, they are<br />indirectly supported by observations in living animals that a digit will display features normally<br />associated with the neighbouring medial digit if the latter fails to chondrify in early development21,<br />that phalangeal counts can vary even within species29, 42 and that secondarily cartilaginous<br />elements can regain their ability to ossify43.<br /><br />If BDR applies to the more inclusive Averostra, as the II-III-IV hypothesis suggests, early stages of<br />tetanuran evolution must have involved loss of the already highly reduced metacarpal I, reduction<br />in the length of metacarpal II, and the reappearance of additional phalanges on metacarpal IV.<br />Both the I-II-III and II-III-IV hypotheses can claim a degree of support from morphological data,<br />but the II-III-IV hypothesis is more parsimonious when developmental data from extant birds are<br />considered.Dr. Pterosaurhttps://www.blogger.com/profile/13137867768653523183noreply@blogger.comtag:blogger.com,1999:blog-3049195237412585561.post-66886451753736537132015-11-28T07:43:31.623-08:002015-11-28T07:43:31.623-08:00Can copy and paste from (2009):
http://www2.gwu.ed...Can copy and paste from (2009):<br />http://www2.gwu.edu/~newsctr/newscenter/research/dinosaur/clark.pdfDr. Pterosaurhttps://www.blogger.com/profile/13137867768653523183noreply@blogger.comtag:blogger.com,1999:blog-3049195237412585561.post-45977268346605878062015-11-27T16:47:19.555-08:002015-11-27T16:47:19.555-08:00TNT free download:
http://www.lillo.org.ar/phylog...TNT free download:<br /><br />http://www.lillo.org.ar/phylogeny/tnt/<br />Dr. Pterosaurhttps://www.blogger.com/profile/13137867768653523183noreply@blogger.comtag:blogger.com,1999:blog-3049195237412585561.post-40143494363461357762015-11-27T15:02:43.389-08:002015-11-27T15:02:43.389-08:00https://www.google.ca/url?sa=t&rct=j&q=&am...https://www.google.ca/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0ahUKEwiNouie2rHJAhVF1h4KHT1mBaMQFggcMAA&url=http%3A%2F%2Fwww2.gwu.edu%2F~newsctr%2Fnewscenter%2Fresearch%2Fdinosaur%2Fclark.pdf&usg=AFQjCNFndKzJ5OberUETly0U3A8QMEei7Q&sig2=USwYNw6Ocmcz1p3vrrmiWQ&bvm=bv.108194040,d.dmo<br /><br />Theropods have traditionally been assumed to have lost manual digits from the lateral side inward,<br />which differs from the bilateral reduction pattern seen in other tetrapod groups. This unusual<br />reduction pattern is clearly present in basal theropods, and has also been inferred in non-avian<br />tetanurans based on identification of their three digits as the medial ones of the hand (I-II-III). This<br />contradicts the many developmental studies indicating II-III-IV identities for the three manual<br />digits of the only extant tetanurans, the birds.Dr. Pterosaurhttps://www.blogger.com/profile/13137867768653523183noreply@blogger.comtag:blogger.com,1999:blog-3049195237412585561.post-80228275907034968912015-11-27T13:09:42.402-08:002015-11-27T13:09:42.402-08:00An Archaeopteryx-like theropod from
China and the ...An Archaeopteryx-like theropod from<br />China and the origin of Avialae<br />Xing Xu1,2, Hailu You3, Kai Du4 & Fenglu Han2<br />http://www.researchgate.net/publication/51527707_An_Archaeopteryx-like_theropod_from_China_and_the_origin_of_Avialae._Nature<br /><br />http://www.nature.com/nature/journal/v475/n7357/full/nature10288.html<br /><br />(we identify the three manual digits of Xiaotingia<br />and other maniraptorans as II-III-IV, rather than as I-II-III as in<br />many other studies8).Dr. Pterosaurhttps://www.blogger.com/profile/13137867768653523183noreply@blogger.comtag:blogger.com,1999:blog-3049195237412585561.post-9688290479226253332015-11-26T15:53:25.489-08:002015-11-26T15:53:25.489-08:00http://digitallibrary.amnh.org/handle/2246/6112
In...http://digitallibrary.amnh.org/handle/2246/6112<br />In summary, Pterosauromorpha is well supported as the sister taxon to Dinosauromorpha.Dr. Pterosaurhttps://www.blogger.com/profile/13137867768653523183noreply@blogger.comtag:blogger.com,1999:blog-3049195237412585561.post-15446068078303501572015-11-24T15:52:17.883-08:002015-11-24T15:52:17.883-08:002009 study:
A Jurassic ceratosaur from China helps...2009 study:<br />A Jurassic ceratosaur from China helps clarify avian digital homologiesDr. Pterosaurhttps://www.blogger.com/profile/13137867768653523183noreply@blogger.comtag:blogger.com,1999:blog-3049195237412585561.post-81169580164556675922015-11-20T17:47:27.913-08:002015-11-20T17:47:27.913-08:00Lone Star pterosaurs:
http://www.researchgate.net/...Lone Star pterosaurs:<br />http://www.researchgate.net/publication/259437218_Lone_Star_Pterosaurs<br />Dr. Pterosaurhttps://www.blogger.com/profile/13137867768653523183noreply@blogger.comtag:blogger.com,1999:blog-3049195237412585561.post-31361044827563776242015-11-18T06:21:41.166-08:002015-11-18T06:21:41.166-08:00A significant 2009 study:
http://www.nature.com/ar...A significant 2009 study:<br />http://www.nature.com/articles/nature08124.epdf?referrer_access_token=1LIOYM249T2ALXmHhUVXQtRgN0jAjWel9jnR3ZoTv0NAxxXDTxDgb7tt7vNCs5i7CDx_p1E8pIL0dPMGIw0CIZ1LRnUZIDT1a3FIDY_UW4FRwpODRDVwWg-KbK448VK63yIXiGAa_H8fA42yVK8TsNhr_ASjWKKTbM-PJCMVzpKKElR4FEstewHl9DZGaHr9&tracking_referrer=www.nature.com<br />Dr. Pterosaurhttps://www.blogger.com/profile/13137867768653523183noreply@blogger.com