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Unser Haushund: Eine Spitzmaus im Wolfspelz? - Wolf-Ekkehard ... Unser Haushund: Eine Spitzmaus im Wolfspelz? - Wolf-Ekkehard ...

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364“Single tree from parsimony analysis of combined molecular and phenomic data mapped onto the stratigraphic record (tables S2and S3). Crown clade Placentalia diversified after the K-Pg boundary with only the stem lineage to Placentalia crossing theboundary. Black boxes indicate fossil taxa hypothesized to be on lineages; black lines indicate stratigraphic ranges; ranges andghost lineages 743 (orange) provide minimum divergence dates. When the matrix includes only one terminal taxon of a crownorder, two boxes appear: the oldest hypothesized member of the crown clade (the younger date) and the oldest hypothesizedtaxon on the stem to the crown clade (the older date). Crown clades (except Eutheria and Metatheria) are defined (table S4).Space immediately younger than 65 Ma not to scale showing early Paleocene interordinal diversification of Placentalia. Crownclades Marsupialia and Monotremata also diversified post K-Pg boundary. Bremer support (BS) (table S8) above nodes,jackknife values below nodes.”Canis lupus ist darin übrigens unter “57“ vermerkt.Zusammenfassend zur Arbeit von O’Leary et al. (2013) noch einmal ein paarHauptpunkte aus dem Kommentar von Greg Mayer im Kontext (2013):“[T]here is no particular known fossil which is being identified as or compared to this placentalcommon ancestor; the ancestor in the picture, as stressed here, is hypothetical. Yet, the Times articleidentifies Protungulatum as the ancestral placental, O’Leary et al. most definitely do not do do: theyidentify Protungulatum as a member of the lineage that gave rise to (most) hoofed mammals (i.e. quite farfrom the common ancestor of all placentals). Protungulatum is the oldest known member of the clade thatincludes all extant placentals, but that does not make it the common ancestor.”Wie ist nun in diese Ergebnisse von O’Leary et al. das Paper von Luo et al. von2011 zu Juramaia sinensis zu integrieren?In der Arbeit O’Leary et al. (2013) wird das Paper von Luo et al. zwar unter der19. Referenz im Literaturverzeichnis aufgeführt, aber erstaunlicherweise nichtkommentiert. Auf p. 665 lasen wir bei O’Leary et al. zu Eomaia (siehe oben):“The Cretaceous fossil Eomaia scansoria (125 Ma) has previously been called a placental (18) oreutherian (11, 18, 19); however, we find with 100% jackknife support that Eomaia falls outside ofEutheria as a stem taxon to Theria.”Eomaia scansoria ist jedoch das Fossil, welches John Roach (2002) in derZeitschrift National Geographic als ”[The] Earliest Known Ancestor of PlacentalMammals Discovered“ bezeichnet hatte. Roach berichtete am 24. April 2002 744(fett vom Verfasser, außer “shrew-like species” und Eomaia scansoria):“Researchers today announced the discovery of the earliest known ancestor of the group of mammalsthat give birth to live young. The finding is based on a well-preserved fossil of a tiny, hairy 125-millionyear-oldshrewlike species that scurried about in bushes and the low branches of trees."We found the earliest ancestor, perhaps a great uncle or aunt, or perhaps a great grandparent—albeit125 million years removed—to all placental mammals," said Zhe-Xi Luo, a paleontologist at theCarnegie Museum of Natural History in Pittsburgh, Pennsylvania. "It is significant because a vastmajority of mammals alive today are placentals."Cows, rats, monkeys, lions, tigers, and pandas are placentals. Dogs, rhinoceroses, tree sloths, horses, andwhales are placentals. And, of course, humans are placentals.The fossil of the animal, named Eomaia scansoria, was found in the fossil-rich region of LiaoningProvince in China, which has also produced ancient evidence of feathered dinosaurs and primitive birds.Eomaia, which means "ancient mother" in Greek, was five inches (14 centimeters) long and weighed nomore than 0.9 ounces (25 grams)."It tells us that the placental lineage has a much earlier origin than previously thought," said Luo, coauthorof a paper on the discovery in the April 25 issue of Nature.743 Anne D. Yoder erklärt (2013: Fossils Versus Clocks. Science 339: 656-658) den von O’Leary et al. in ihrem Paper und im Supplementinsgesamt 8 Mal gebrauchten Begriff “ghost lineage“ (2013, pp. 657/658) sehr gelungen wie folgt:“For age estimation, they turned to fossil calibrations and a rarely used method, ghost lineage analysis. Typical molecular phylogenetic studies usefossils as the variable for solving the molecular rate equation. The ghost lineage approach instead uses the defining morphological characteristics thatalign fossils with living clades to calibrate the phylogeny as a whole. This it does by using direct fossil evidence for the earliest appearance of lineagesand by inferring the presence of “ghost lineages” not documented in the fossil record but implied by sister-group relationships.To understand the method, consider the lemurs of Madagascar. There are no known fossil lemurs, only unfossilized bones of lemurs that went extinct inthe past 12,000 years. A direct reading of this record would yield the conclusion that lemurs evolved a few thousand years ago. However, we know thatthe closest relatives of lemurs are the Lorisiformes of Africa and Asia. The fossil record reveals that within the Lorisiformes, lorises and galagos divergedfrom each other by 39 million years ago, thus establishing a minimum age for lorisiforms and—because lemurs must have split off before thatdivergence— for lemurs. Thus, we infer that the lemurs are the product of a ghost lineage that has persisted for at least 40 million years.”744 Siehe wieder http://news.nationalgeographic.com/news/2002/04/0423_020425_firstmammal.html

365The finding indicates that the earliest extinct relatives of placentals had a much greater diversity thanpreviously thought, Luo said, and "tells us about the ancestral morphology from which all placentals wouldhave descended.""Wie sah Eomaia scansoria aus und wovon lebte sie? Antwort: “The feet ofEomaia indicate that the tiny creature was adapted to climbing trees and bushes,where it probably fed on insects much like modern-day shrews, said Luo.” 745Zur zeitlichen Einordnung wurde seinerzeit von mehreren Autoren besondershervorgehoben, dass mit diesem Fund nun endlich die molekularen Resultatebetätigt wurden (fett hervorgehoben wieder von John Roach; 2002, p. 2):“Recent molecular analyses of mammalian DNA conducted by biologists such as Mark Springer at theUniversity of California at Riverside suggest that the split took place more than 100 million years ago.Until now, however, there was no definitive skeletal fossil evidence to substantiate these studies."Our molecular results suggest that living placental mammals have a common ancestor about 105million years ago," said Springer. "[Other] molecular data also suggest a much earlier split between livingplacentals and living marsupials—about 175 million years ago. If we evaluate the new fossil in thisframework, it is entirely expected that we should find stem placentals that are this old, and older."Some scientists, such as Weil, speculate that the 175-million-year time frame for the split may be anoverestimate. But the discovery of Eomaia, along with four other recently discovered mammalian fossils inthe Yixian Formation of the Liaoning Province, indicates that indeed there was great mammaliandiversity 125 million years ago.“Ähnlich J. Roach (“hairy 125-million-year-old shrewlike species”) sprach Erik Stokstad inScience vom 25. April 2002 746 ebenfalls von “the shrew-sized creature“ (10 cmlang, aber rundlicher, ca. 20-25g schwer) und betont unter der Überschrift “TheSibling of All Placentals“, dass sich jetzt die paläontologischen Funde denmolekularen Daten nähern (Hervorhebungen im Schriftbild jetzt wieder von mir):“The ancient lakebeds of China's Liaoning Province, renowned for their treasure trove of feathereddinosaurs, have yielded a gem of another sort: the complete, fur-shrouded skeleton of the most ancientplacental mammal yet discovered. […] Eomaia's age and characteristics place it near the base of theplacental-mammal family tree. […]Eomaia also goes a little way toward closing a long-standing gap between fossil evidence andmolecular dates for milestones in mammalian history. According to molecular geneticists, eutheriansdiverged from marsupials 170 million years ago. The latest molecular data also suggest that modern ordersof mammals arose and began to diversify about 104 million years ago - some 40 million years before theirundisputed fossil record begins. By showing that placental mammals had already begun diversifying by 125million years ago, Luo says, his team's fossil meshes with the molecular evidence. But others say thatbecause Eomaia doesn't belong to a modern order, it leaves the major discrepancy unchanged.”Der Originalartikel von Ji et al. (2002) ist betitelt: “The earliest known eutherianmammal“. 747 Wie oben aufgeführt, handelt es sich jedoch nach O’Leary et al.(2013) bei Eomaia scansoria weder um einen Plazentalier noch gehört sie zu denEutheria. Fazit: Sie gehört damit (auch) nach evolutionstheoretischenVoraussetzungen nicht zu den Vorfahren der Theria 748 .745 http://news.nationalgeographic.com/news/2002/04/0423_020425_firstmammal_2.html746 http://news.sciencemag.org/sciencenow/2002/04/25-03.html747 Qiang Ji, Zhe-Xi Luo, Chong-Xi Yuan, John R. Wible, Jian-Ping Zhang and Justin A. Georgi (2002): The earliest known eutherian mammal. Nature416, 816-822. Abstract: “The skeleton of a eutherian (placental) mammal has been discovered from the Lower Cretaceous Yixian Formation ofnortheastern China. We estimate its age to be about 125 million years (Myr), extending the date of the oldest eutherian records with skull and skeleton byabout 40–50 Myr. Our analyses place the new fossil at the root of the eutherian tree and among the four other known Early Cretaceous eutherians, andsuggest an earlier and greater diversification of stem eutherians that occurred well before the molecular estimate for the diversification of extant placentalsuperorders (104–64 Myr). The new eutherian has limb and foot features that are known only from scansorial (climbing) and arboreal (tree-living) extantmammals, in contrast to the terrestrial or cursorial (running) features of other Cretaceous eutherians. This suggests that the earliest eutherian lineagesdeveloped different locomotory adaptations, facilitating their spread to diverse niches in the Cretaceous.“748 “Theria ([…] Greek: θηρίον, wild beast) is a subclass of mammals[1] that give birth to live young without using a shelled egg, consisting of theeutherians (including the placental mammals) and the metatherians (including the marsupials). The only omitted extant mammal group is the egg-layingmonotremes.“

365The finding indicates that the earliest extinct relatives of placentals had a much greater diversity thanpreviously thought, Luo said, and "tells us about the ancestral morphology from which all placentals wouldhave descended.""Wie sah Eomaia scansoria aus und wovon lebte sie? Antwort: “The feet ofEomaia indicate that the tiny creature was adapted to cl<strong>im</strong>bing trees and bushes,where it probably fed on insects much like modern-day shrews, said Luo.” 745Zur zeitlichen Einordnung wurde seinerzeit von mehreren Autoren besondershervorgehoben, dass mit diesem Fund nun endlich die molekularen Resultatebetätigt wurden (fett hervorgehoben wieder von John Roach; 2002, p. 2):“Recent molecular analyses of mammalian DNA conducted by biologists such as Mark Springer at theUniversity of California at Riverside suggest that the split took place more than 100 million years ago.Until now, however, there was no definitive skeletal fossil evidence to substantiate these studies."Our molecular results suggest that living placental mammals have a common ancestor about 105million years ago," said Springer. "[Other] molecular data also suggest a much earlier split between livingplacentals and living marsupials—about 175 million years ago. If we evaluate the new fossil in thisframework, it is entirely expected that we should find stem placentals that are this old, and older."Some scientists, such as Weil, speculate that the 175-million-year t<strong>im</strong>e frame for the split may be anoverest<strong>im</strong>ate. But the discovery of Eomaia, along with four other recently discovered mammalian fossils inthe Yixian Formation of the Liaoning Province, indicates that indeed there was great mammaliandiversity 125 million years ago.“Ähnlich J. Roach (“hairy 125-million-year-old shrewlike species”) sprach Erik Stokstad inScience vom 25. April 2002 746 ebenfalls von “the shrew-sized creature“ (10 cmlang, aber rundlicher, ca. 20-25g schwer) und betont unter der Überschrift “TheSibling of All Placentals“, dass sich jetzt die paläontologischen Funde denmolekularen Daten nähern (Hervorhebungen <strong>im</strong> Schriftbild jetzt wieder von mir):“The ancient lakebeds of China's Liaoning Province, renowned for their treasure trove of feathereddinosaurs, have yielded a gem of another sort: the complete, fur-shrouded skeleton of the most ancientplacental mammal yet discovered. […] Eomaia's age and characteristics place it near the base of theplacental-mammal family tree. […]Eomaia also goes a little way toward closing a long-standing gap between fossil evidence andmolecular dates for milestones in mammalian history. According to molecular geneticists, eutheriansdiverged from marsupials 170 million years ago. The latest molecular data also suggest that modern ordersof mammals arose and began to diversify about 104 million years ago - some 40 million years before theirundisputed fossil record begins. By showing that placental mammals had already begun diversifying by 125million years ago, Luo says, his team's fossil meshes with the molecular evidence. But others say thatbecause Eomaia doesn't belong to a modern order, it leaves the major discrepancy unchanged.”Der Originalartikel von Ji et al. (2002) ist betitelt: “The earliest known eutherianmammal“. 747 Wie oben aufgeführt, handelt es sich jedoch nach O’Leary et al.(2013) bei Eomaia scansoria weder um einen Plazentalier noch gehört sie zu denEutheria. Fazit: Sie gehört damit (auch) nach evolutionstheoretischenVoraussetzungen nicht zu den Vorfahren der Theria 748 .745 http://news.nationalgeographic.com/news/2002/04/0423_020425_firstmammal_2.html746 http://news.sciencemag.org/sciencenow/2002/04/25-03.html747 Qiang Ji, Zhe-Xi Luo, Chong-Xi Yuan, John R. Wible, Jian-Ping Zhang and Justin A. Georgi (2002): The earliest known eutherian mammal. Nature416, 816-822. Abstract: “The skeleton of a eutherian (placental) mammal has been discovered from the Lower Cretaceous Yixian Formation ofnortheastern China. We est<strong>im</strong>ate its age to be about 125 million years (Myr), extending the date of the oldest eutherian records with skull and skeleton byabout 40–50 Myr. Our analyses place the new fossil at the root of the eutherian tree and among the four other known Early Cretaceous eutherians, andsuggest an earlier and greater diversification of stem eutherians that occurred well before the molecular est<strong>im</strong>ate for the diversification of extant placentalsuperorders (104–64 Myr). The new eutherian has l<strong>im</strong>b and foot features that are known only from scansorial (cl<strong>im</strong>bing) and arboreal (tree-living) extantmammals, in contrast to the terrestrial or cursorial (running) features of other Cretaceous eutherians. This suggests that the earliest eutherian lineagesdeveloped different locomotory adaptations, facilitating their spread to diverse niches in the Cretaceous.“748 “Theria ([…] Greek: θηρίον, wild beast) is a subclass of mammals[1] that give birth to live young without using a shelled egg, consisting of theeutherians (including the placental mammals) and the metatherians (including the marsupials). The only omitted extant mammal group is the egg-layingmonotremes.“

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