A Christmas story: the three kings and the star of Bethlehem

Taking a break
from vertebrate paleontology today, as we dive into pre-history and astronomy.

I hope
you are home with loved ones or traveling to visit them.

Recently I heard an interesting story
about the three stars that create ‘the belt’ in the constellation of OrionAlnitak, Alnilam and Mintaka. As the three stars rise in the evening sky of December 24th, they were supposed to point to the dawn on the morning of the 25th, three days after the Winter solstice, the shortest day of the year. Thus in both pagan lore and Christmas stories we have a rising sun, three days after a dying sun, that gives hope to the world that everything is going to be okay: we’re going to have another growing season and harvest. More importantly, the three stars were sometimes known to the ancients as ‘The Three Kings‘ part of the elusive and enigmatic “Star of Bethlehem” legend of the Christmas story. For some historians, these all seems to tie in with actual, and therefore verifiable astronomical events. Let’s see if the do.

Remember, 
in the days before light pollution and television, people sat around the campfire at night telling stories to their children about their favorite stars and constellations. Some of these random star patterns represented heroes, like Hercules. Others were sea monsters, like Draco. Ultimately the study of astrology, and then the science of astronomy, arose from these legends about the constellations and predictions arising about the movement of the  sun, moon, planets and occasional comets and meteor showers, among them all. There are 12 months and 12 zodiac constellations, not quite 12 revolutions of the moon (close, but no cigar). Every science has its own infancy, and that’s how astronomy had its own genesis.

Curious about the veracity of ‘the three kings’ claim,
I opened up a free constellation program, Stellarium, set the Earth location for Tel-Aviv in Israel, and checked out the star alignments for 2018 (Fig. 1). Unfortunately, the stars of Orion’s belt do not align with the rising sun. They do point straight down as they rise, but the belt line points way too far East of the rising sun of December 25th.

Remember, this old story supposedly took place 2018 years ago…
and there is this thing called precession of the equinoxes that cycles every 26,000 years, moving the constellations around the sky relative to the sun.

Figure 1. In 2018 the stars in the belt of Orion do not align with the rising sun of December 24.

Figure 1. In 2018 the stars in the belt of Orion do not align with the rising sun of December 24. The belt stars are too far East. Even so, the fact that they point straight down is awe inspiring!

Resetting the sky for the year zero,
provides a closer approximation for aligning the belt of Orion with the rising sun (Fig. 2), but still, no real match here. The belt stars of Orion still align too far East relative to the rising sun three days after the Winter solstice. Apparently the legend of ‘the three kings’ did not arise from this era.

Figure 2. Tel Aviv sunrise, year zero with red arrows still showing a lack of alignment between the rising sun and Orion's belt stars.

Figure 2. Tel Aviv sunrise, year zero with red arrows. Still the belt stars are too far East.

Resetting the sky for the year 3000 BC
(5000 years ago) finally aligns the stars of Orion’s belt with the rising sun (Fig. 3). For a bonus, Sirius, the brightest star in the night sky, is also aligned and peeks up over the horizon just before sunrise. Now, that’s a story you can tell your prehistoric kids and grandkids!

Figure 3. About 5000 years ago (3000BC) the three stars of Orion's belt did indeed align with the rising sun, preceded by Sirius the other brightest star near the Winter solstice.

Figure 3. About 5000 years ago (3000BC) the three stars of Orion’s belt did indeed align with the rising sun, preceded by Sirius the other brightest star near the Winter solstice. Maybe that astrological legend goes back that far.

Maybe that special alignment in the morning sky 
of the Winter solstice was the impetus for erecting Stonehenge at that time. That’s true. You can look it up here.

So, about 1000 years before
Wikipedia reports the study of astrology had its genesis, and coeval with the construction of Stonehenge, five important stars were in close alignment on a very important day to our forebearers. That was an event that lasted for several hundred years and came to be legendary long after the stars had drifted East of the rising sun. We still tell the story about the evening those three kings came out of the East to celebrate the rising sun that would give hope for all humanity, year after year.

Happy Holidays everyone!

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‘Taeniodonta’ is polyphyletic, part 3: Conoryctes

The traditional eutherian clade
Taeniodonta‘ is polyphyletic in the large reptile tree (LRT, 1365 taxa, subset Fig. 4). Earlier here and here are parts 1 and 2 of this series.

Figure 1. Conoryctes fossil and drawing from Schoch 1986.

Figure 1. Conoryctes fossil and drawing from Schoch 1986.

Conoryctes comma (originally Hexadon molestus, Cope 1881; Schoch 1986; Paleocene; AMNH 3395). Here the Schoch drawings were not a great match for the fossil data. This taxon nests with the much earlier, Early Cretaceous marsupial, Vincelestes (Fig. 4). These were derived from Huerfanodon (Fig. 5). Note the elevated premaxila, flattened molars and deep dentary. The Schoch 1986 diagnosis of this genus is based on dental traits. He also compared Conoryctes to Huerfanodon, a related taxon in the LRT, but he also compared them to Onychonycteris, an unrelated, but convergent eutherian close to phenacodontids (Fig. 3), which is close to Conoryctella (Fig. 6) another putative taeniodont.

Figure 3. Subset of the LRT labeling several traditional taeniodonts in red, indicating the traditional clade Taeniodonta is polyphyletic and should therefore be abandoned.

Figure 3. Subset of the LRT labeling several traditional taeniodonts in red, indicating the traditional clade Taeniodonta is polyphyletic and should therefore be abandoned.

Conoryctes is so unpopular,
it has no Wikipedia entry.

Figure 4. Vincelestes soul showing the separation of the nasals and frontals by the conjoined maxillae housing giant canine roots, as in sister Thylacosmilus.

Figure 4. Vincelestes soul showing the separation of the nasals and frontals by the conjoined maxillae housing giant canine roots, as in sister Thylacosmilus.

Vincelestes neuquenianus (Bonaparte 1986, Early Cretaceous, 130 mya). Derived from a sister to HuerfanodonVincelestes is a carnivorous marsupial sister to the traditional taeniodont, Conoryctes. Note the hyper-enlarged canines and short rostrum. Premolars were not carnassial in shape, but still able to process by cutting and grinding. Nine individuals are known. Skeleton is probably a chimaera of several specimens and the degree of completion is unknown. The tail is extraordinarily long and provided with deep chevrons. Image from Digimorph.org and used with permission. Scale bar = 1 cm.

Figure 5. Heurfanodon skull. This late survivor of a Jurassic radiation is from the Eocene. It is transitional between didelphids and the Vincelestes-Thylacosmilus clade.

Figure 5. Heurfanodon skull. This late survivor of a Jurassic radiation is from the Eocene. It is transitional between didelphids and the Vincelestes-Thylacosmilus clade.

Huerfanodon torrejonius (Cope 1882; Eocene; AMNH 3224, Schoch 1986, USNM 15412) was traditionally considered a taeniodont, but here nests basal to the VincelestesThylacosmilus clade. Despite its late appearance, this taxon is more primitive than the others, which puts its genesis deep into the Jurassic. In dorsal view the skull is not compressed anterior to the jugals, similar to the ancestral Chironectes.

Figure 6. Conoryctella pattersoni nests with the Eutherian herbivore Onychonycteris in the LRT, not with the marsupial Conoryctes.

Figure 6. Conoryctella pattersoni nests with the Eutherian herbivore Onychonycteris in the LRT, not with the marsupial Conoryctes, according to the LRT, based on the present data.

References
Cope ED 1881. On some Mammalia of the lowest Eocene beds of New Mexico. Palaeontological Bulletin 33:484-495.
Schoch RM 1986. Systematics, functional morphology and macroevolution of the extinct mammalian order Taeniodonta. Bulletin of the Peabody Museum of Natural History, Yale University, New Haven. 307pp.

New book encourages critical thinking in paleontology

Pagnac 2019 brings some fresh views to paleontology courses.
“University dinosaur courses provide an influential venue for developing aptitude beyond knowledge of terrestrial Mesozoic reptiles. Examination of dinosaur paleontology can develop competence in information analysis, perception of flawed arguments, recognition of persuasion techniques, and application of disciplined thought processes.
Three methods for developing critical thought are outlined in this book.
  1. “The first uses dinosaur paleontology to illustrate logical fallacies and flawed arguments.
  2. The second is a method for evaluating primary dinosaur literature by students of any major.
  3. The final example entails critique of dinosaur documentaries based on the appearance of dinosaurs and the disconnect between scientific fact and storytelling techniques.”

Students are owed more than dinosaur facts; lecturers should foster a set of skills that equips students with the tools necessary to be perceptive citizens and science advocates.”

Here at PterosaurHeresies
readers are also provided a set of skills and tools to illustrate logical fallacies and flawed arguments, evaluate and criticize with authority past and present paleo literature and challenge studies flawed by taxon exclusion.

Four questions:

  1. Do paleontologists engage with those critical of their favorite hypotheses?
  2. Do paleontologists ever accept (after rigorous testing) critical thinking that overturns their own pet hypotheses and/or traditional paradigms?
  3. Do paleontologists disrespect critical thinking if it comes from certain sources (ignoring the readily available data while doing so)?
  4. Are paleontologists ever annoyed by the achievements of others?
  5. All of the above?

Take your time in answering these.
Hopefully the Pagnac book will indeed encourage critical thinking. We looked at the lethargy that has always surrounded paleontology here.

References
Pagnac D 2019. Dinosaurs: A Catalyst for Critical Thought Elements of Paleontology

‘Taeniodonta’ is polyphyletic, part 2: Schowalteria

You can find part 1
of “‘Taeniodonta’ is polyphyletic” here. Former ‘taeniodonts’ nest is a variety of nodes in the LRT (see Fig. 5), not as a monophyletic clade.

Figure 1. Showalteria. Not much there. Adding more rounds out the skull, a likely marsupial relative of Vincelestes.

Figure 1. Showalteria. Not much there. Adding more rounds out the skull, a likely marsupial relative of the sabertooth marsupial, Thylacosmilus in figure 2.

Schowalteria clemensi (Fox and Naylor 2003; Maastrichtian, Cretaceous, 68mya) was considered a stylinodont, taeniodont eutherian, but here nests with the marsupial sabertooth, Thylacosmilus (Fig. 2), if the bones above have been correctly identified. Otherwise, Thylacosmilus has no close relatives in the LRT. A traditional close relative, Patagosmilus, was shifted away earlier.

Figure 2. Thylacosmilus skull. Note the deep maxillae in dorsal contact containing giant canine roots. These are not present in Patagosmilus.

Figure 2. Thylacosmilus skull. Note the deep maxillae in dorsal contact containing giant canine roots. These are not present in Patagosmilus.

Thylacosmilus atrox (Riggs 1933; Miocene, 40-3 mya; 1 m long) was a leopard-like predator, but plantigrade derived from a sister to Schowalteria. The premaxillary teeth are absent here, perhaps lost during taphonomy. The canines are enlarged to curved fangs. Their roots extend above the orbits. The dentary has ventral processes that guide and protect them. The lower canines are round stubs. Tiny lower incisors appear between them. The coronoid process is small, indicating a wide, but weak bite. Both Thylacosmilus and Schowalteria were derived from a sister to Vincelestes (Fig. 3) in the Early Cretaceous.

Figure 4. Vincelestes soul showing the separation of the nasals and frontals by the conjoined maxillae housing giant canine roots, as in sister Thylacosmilus.

Figure 3. Vincelestes soul showing the separation of the nasals and frontals by the conjoined maxillae housing giant canine roots, as in sister Thylacosmilus.

Vincelestes neuquenianus (Bonaparte 1986, Early Cretaceous, 130 mya). Derived from a sister to Huerfanodon (Fig. 5), Vincelestes is a carnivorous marsupial sister to the traditional taeniodont, Conoryctes. Note the hyper-enlarged canines and short rostrum. Premolars were not carnassial in shape, but still able to process by cutting and grinding. Nine individuals are known. Skeleton is probably a chimaera of several specimens and the degree of completion is unknown. The tail is extraordinarily long and provided with deep chevrons. Image from Digimorph.org and used with permission. Scale bar = 1 cm.

Figure 5. Heurfanodon skull. This late survivor of a Jurassic radiation is from the Eocene. It is transitional between didelphids and the Vincelestes-Thylacosmilus clade.

Figure 4. Heurfanodon skull. This late survivor of a Jurassic radiation is from the Eocene. It is transitional between didelphids and the Vincelestes-Thylacosmilus clade.

Huerfanodon torrejonius (Cope 1882; Eocene; AMNH 3224, Schoch 1986, USNM 15412) was traditionally considered a taeniodont, but here nests basal to the VincelestesThylacosmilus clade. Despite its late appearance, this taxon is more primitive than the others, which puts its genesis deep into the Jurassic. In dorsal view the skull is not compressed anterior to the jugals, similar to the ancestral Chironectes.

Figure 3. Subset of the LRT labeling several traditional taeniodonts in red, indicating the traditional clade Taeniodonta is polyphyletic and should therefore be abandoned.

Figure 5. Subset of the LRT labeling several traditional taeniodonts in red, indicating the traditional clade Taeniodonta is polyphyletic and should therefore be abandoned.

References
Bonaparte JF 1986. Sobre Mesungulatum houusayi y nuevos mamíferos Cretácicos de Patagonia, Argentina [On Mesungulatum houssayi and new Cretaceous mammals from Patagonia, Argentina]. Actas del IV Congreso Argentino de Paleontología y Biostratigrafía 2:48-61.
Cope ED 1881. On some Mammalia of the lowest Eocene beds of New Mexico. Palaeontological Bulletin 33:484-495.
Cope ED 1882. Contributions to the history of the Vertebrata of the lower Eocene of Wyoming and New Mexico, made during 1881. Proceedings of the American Philosophical Society 20(111):139-197.
Fox RC and Naylor BG 2003. A Late Cretaceous taeniodont (Eutheria, Mammalia) from Alberta, Canada. Neues Jahrbuch für Geologie und Paläontologie. 229 (3):393–420.
Riggs EC 1934. A new marsupial saber-tooth from the Pliocene of Argentina and its relationships to other South American predacious marsupials. Transactions of the American Philosophical Society 24, 1–32.
Schoch RM 1986. Systematics, functional morphology and macroevolution of the extinct mammalian order Taeniodonta. Bulletin of the Peabody Museum of Natural History, Yale University, New Haven. 307pp.

wiki/Vincelestes
wiki/Thylacosmilus
wiki/Schowalteria
wiki/Taeniodonta

Machaeroides and Kerberos enter the LRT

Machaeroides and Kerberos enter the LRT
as related to one another, and both basal to clades within the Carnivora, apart from prior sister candidates. Apparently taxon exclusion was a problem in earlier analyses. Taxon exclusion is minimized in the large reptile tree (LRT, 1364 taxa).

Figure 1. Subset of the LRT focusing on the Mustela clade within the Carnivora with the addition of Kerberos and Machaeroides.

Figure 1. Subset of the LRT focusing on the Mustela clade within the Carnivora with the addition of Kerberos and Machaeroides.

Machaeroides eothen (Matthew 1909; early Eocene, 56mya) has been difficult to nest, with some experts labeling this genus close to Oxyaena, a marsupial creodont. With more taxa sabertooth Machaeroides nests at the base of the StylinodonPsittacotherium clade within the clade Carnivora. Canines are emphasized in this clade. The maxilla contacts the orbit above the lacrimal.

Figure 2. Two Machaeroides skulls in the three views.

Figure 2. Two Machaeroides skulls in the three views.

Kerberos langebadreae (Solé et al. 2015; Middle Eocene, 45 mya) was originally described as sister to the marsupial Hyaenodon. Here Kerberos nests at the base of the Sarkastodon and Patriofelis clade within the larger placental clade, Carnivora. The skull is lower and longer and includes more premolars along with smaller canines.

Figure 3. Kerberos skull in 3 views and colored using DGS methods.

Figure 3. Kerberos skull in 3 views and colored using DGS methods. Perhaps the posterior skull was lower in vivo to match the jaw joint.

References
Matthew WD 1909. The Carnivora and Insectivora of the Bridger Basin, middle Eocene. Memoirs of the American Museum of Natural History 9:289-567.
Solé F, Amson E, Borths M, Vidalenc D, Morlo M, Bastl K 2015. A New Large Hyainailourine from the Bartonian of Europe and Its Bearings on the Evolution and Ecology of Massive Hyaenodonts. (Mammalia). PLoS ONE 10(9): e0135698.
doi:10.1371/journal.pone.0135698

The clade ‘Taeniodonta’ is polyphyletic, part 1: Cimolestes

Rule #1: More taxa more precisely nest all taxa
Once again, latest Cretaceous Cimolestes goes under review, this time with many more candidate sister taxa. At present the best material for this genus is a single mandible with a complete set of teeth (Fig. 1). Rook and Hunter 2013 nest Cimolestes as the direct outgroup to the tradtional clade Taeniodonta.

According to Wikipedia,
“[Members of the genus Cimolesteswere once considered to be marsupials, then primitive placental mammals, but now are considered to be members of the order Cimolesta (which was named after the genus), outside of placental mammals proper (Rook and Hunter 2013). Before they were determined to be non-placental eutherians, the cimolestids were once considered the common ancestral group of the clades Carnivora and the extinct Creodonta.”

Figure 1. Cimolestes is represented by a toothy mandible. Here it nests with the extant Dasyurus if the back of the skull is shorter. Apparently the coronoid process is oddly narrow.

Figure 1. Cimolestes is represented by a toothy mandible. Here it nests with the extant Dasyurus if the back of the skull is shorter. Apparently the coronoid process is oddly narrow. I have not seen incisors like this in any other mammal, but Dasyurus comes close.

With so few traits to score,
Cimolestes is difficult to nest and generally causes loss of resolution, especially when other taxa data include skulls without mandibles (so, no comparable traits = loss of resolution). When deleting taxa without preservation of the mandibles the best match is with the extant marsupial, Dasyurus (Fig. 1), but with a narrower coronoid process and larger incisors, and therefore a likely shorter and smaller cranial region.

Figure 2. Traditional Taeniodonta in a cladogram. With more taxa this clade splits up according to the colors shown here.

Figure 2. Traditional Taeniodonta in a cladogram from Rook and Hunter 2013. Colors and list of body parts added here. With more taxa to be attracted to (1362 in the LRT) this clade splits up according to the three colors shown here.

Traditionally
Cimolestes is considered a basal taeniodont and all taeniodonts are considered eutherians (placentals). Other traditional taeniodonts include Protictis, Onychodectes and Stylinodon. The Rook and Hunter cladogram of eutherian relationships nests only one traditional taeniodont alongside Cimolestes (Fig. 3) and the basalmost member of the tenrec-odontocete clade (in the LRT), Maelestes.

Figure 3. The Rook and Hunter cladogram that nested traditional Taeniodonts within their Eutheria. Colors and tones added here for clarity and comparison. The LRT does not confirm most of these relationships.

Figure 3. The Rook and Hunter cladogram that nested traditional Taeniodonts within their Eutheria. Colors and tones added here for clarity and comparison. The LRT does not confirm most of these relationships.

In the large reptile tree (LRT, 1362 taxa, subset Fig. 4) none of these taxa nest with one another. Their previous joining may be due to eyeballing, a reliance on dental traits and taxon exclusion. That’s all Cope had available at the time. Modern workers appear to have followed traditional taxon lists and convergent dental traits without testing a wider gamut of taxa. The LRT includes more taxa and does not emphasize dental traits.

When tested with additional taxa,
(Fig. 4) the traditional eutherian clade Taeniodonta is polyphyletic and should be abandoned. Only a few traditional members are closely related to one another.

Figure 3. Subset of the LRT labeling several traditional taeniodonts in red, indicating the traditional clade Taeniodonta is polyphyletic and should therefore be abandoned.

Figure 3. Subset of the LRT labeling several traditional taeniodonts in red, indicating the traditional clade Taeniodonta is polyphyletic and should therefore be abandoned.

As typical,
taxa in the LRT provide and document a gradual accumulation of derived traits that competing cladograms cannot match.

More former taeniodonts to come.

References
Fox RC 2015. A revision of the Late Cretaceous–Paleocene eutherian mammal Cimolestes Marsh, 1889. Canadian Journal of Earth Sciences (advance online publication) doi: 10.1139/cjes-2015-0113.
Marsh OC 1889. Marsupialia, Cimolestidae. American Journal of Science and Arts 3d ser., XXXVIII, 89, pl. iv, figs. 8–19.
Rook DL and Hunter JP 2013. Rooting around the eutherian family tree: the origin and relations of the Taeniodonta. Journal of Mammal Evolution
DOI 10.1007/s10914-013-9230-9

wiki/Cimolestes
wiki/Taeniodonta
wiki/Cimolesta

Marsupial sabertooth taxa are polyphyletic

Traditionally
sabertooth marsupials nest together with other carnivorous marsupials in a clade Cope 1875 called Creodonta and Ameghino 1895 called Saprassodonta (back when creodonts were considered archaic placentals).

Figure 1. Patagosmilus to scale alongside Hadrocodium. These sabetooth taxa are not directly related to Thylacosmilus in the LRT.

Figure 1. Patagosmilus to scale alongside Hadrocodium. These sabetooth taxa are not directly related to Thylacosmilus in the LRT. Note the shallow rooted canine. Note the first molar is now the last premolar, contra the original drawing interpretation. The premaxilla is hypothetical based on phylogenetic bracketing and not scored. At a screen resolution of 72 dpi (standard) these are full scale images.

Patagosmilus goini (Fig. 1; Forasiepi and Carlini 2010) is a large sabertooth marsupial from the Middle Miocene of south America traditionally considered a sister to the more famous and distinctly different and more famous sabertooth from South America, Thylacosmilus (Fig. 2). After testing in the large reptile tree (LRT, 1361 taxa), Patagosmilus nests with the ultra tiny basal sabertooth metatherian, Hadrocodium (Figs. 1,3) from the Early Jurassic. Evidently transitional taxa have yet to be discovered (or tested).

Figure 2. Thylacosmilus skull. Note the deep maxillae in dorsal contact containing giant canine roots. These are not present in Patagosmilus.

Figure 2. Thylacosmilus skull. Note the deep maxillae in dorsal contact containing giant canine roots. These are not present in Patagosmilus.

A little backstory:
Thylacosmilus atrox (Riggs 1933; Miocene, 40-3 mya; 1 m long) was a leopard-like predator, but plantigrade. Thylacosmilus was a sister to Early Cretaceous Vincelestes. The premaxillary teeth are either absent or were taphonomivally lost here. The canines are enlarged to curved fangs. Their long roots extend above the orbits. The dentary has deep ventral processes that guide and protect the canines. The lower canines are round stubs. The coronoid process is small. The mandible was able to open nearly 90º.

Figure 3. Tiny Hadrocodium (Early Jurassic) nests as a sister to Patagosmilus (middle Miocene) in the LRT.

Figure 3. Tiny Hadrocodium (Early Jurassic) nests as a sister to Patagosmilus (middle Miocene) in the LRT.

Hadrocodium wui (Luo, Crompton and Sun 2001; Early Jurassic; skull length: 1.2cm), known only from a tiny skull about the size of a thumbnail, Hadrocodium was originally considered a juvenile basal mammal, but later a tiny adult. Hadrocodium has a relatively larger brain size and more advanced ear structure than MegazostrodonHadrocodium nests with other basal metatherians with three (not two) molars, Morganucodon and Volaticotherium. The first molar was originally considered the third premolar.

Figure 4. Vincelestes soul showing the separation of the nasals and frontals by the conjoined maxillae housing giant canine roots, as in sister Thylacosmilus.

Figure 4. Vincelestes soul showing the separation of the nasals and frontals by the conjoined maxillae housing giant canine roots, as in sister Thylacosmilus.

Contra traditional studies
none of these taxa are related to marsupial creodonts and/or borhyaenids, like Borhyaena and Hyaenodon (Fig. 5), all of which have large canine teeth, none of which have saber teeth.

Figure 5. Subset of the LRT focusing on the Metatheria. Here sabertooth Patagosmilus nests far apart from sabertooth Thylacosmilus, which nests apart from the clade of borhyaenid marsupials.

Figure 5. Subset of the LRT focusing on the Metatheria. Here sabertooth Patagosmilus nests far apart from sabertooth Thylacosmilus, which nests apart from the clade of borhyaenid marsupials. A red square is placed next to Carnivora to indicate the presence of Smilodon, Haplophoneus and other sabertooth cats.

Oddly,
elephants, walruses, deer and other taxa with hyper-elongated teeth are never considered sabertooth proboscidians, sabertooth seals and sabertooth deer. Perhaps this is so because such teeth have a round cross-section, not a narrow, sword/saber-like morphology.

References
Ameghino F 1892. (Issued in 1894.) Enumeration synoptique deses pesces de mammiferes fossilesdes formation sócénes de Patagonie. Boletindela, Academia Nacionalde Cienciasen Cordoba, XIII, p.259 (p.108 in reprint).
Cope ED 1875. On the Supposed Carnivora of the Eocene of the Rocky Mountains. Proceedings of the Academy of Natural Sciences, Philadelphia. pp. 444–449.
Forasiepi AM and Carlini AA 2010. A new thylacosmilid (Mammalia, Metatheria, Sparassodonta) from the Miocene of Patagonia. Zootaxa. 2552, ss. 55–68.

wiki/Patagosmilus
wiki/Volaticotherium
wiki/Morganucodon
wiki/Hadrocodium