#cotyle

[scrawliebout]

WIPE THAT FUCKING SMILE OFF YOUR FACE

[ortut]

Peter Sharp 1. Shallows, 2021 2. Cotyl 2, 2021 (Oil and acrylic on linen)

[bm-european-art]

Cotyle Riparia, John Gould, Brooklyn Museum: European Art

Size: Sheet: 21 1/4 x 14 1/2 in. (54 x 36.8 cm) Medium: Lithograph on wove paper

https://www.brooklynmuseum.org/opencollection/objects/84241

[transparentgentlemenmarker]

L'articulation de la hanche est aussi appelé articulation coxo-fémorale cette articulation relie notre tronc avec la partie inférieure du corps, permet de soutenir notre poids quand nous sommes à la fois debout et en mouvement. Puisqu'il s'agit d'une d'une articulation, la hanche se compose de deux os et est enveloppée dans la capsule synoviale, qui a une texture fibreuse et qui permet aux deux os de se déplacer ensemble sans poser de problèmes.

Comment s'appelle l'os de la hanche. L'articulation de la hancheest aussi appelée articulation coxo-fémorale. Cette articulation relie notre tronc avec la partie inférieure du corps, permet de soutenir notre poids quand nous sommes à la fois debout et en mouvement. Puisqu'il s'agit d'une d'une articulation, la hanche se compose de deux os et est enveloppée dans la capsule synoviale, qui a une texture fibreuse et qui permet aux deux os de se déplacer ensemble sans poser de problèmes. Étant donné qu'il s'agit d'une articulation, la hanche est composée de deux os qui travaillent ensemble pour nous permettre d'avoir une mobilité et un équilibre correcte, ce qui permet de stabiliser le poids de notre corps. Les os de la hanche sont l'os coxal : il est composé de trois os : l'ilon, le isquion, qu'on appelle également l'os du pelvis. Cet os dispose d'une zone articulaire très importante, le cotyle ou le acetabulum, une zone couverte par le cartilage faisant partie de la tête du fémur ou de la tête fémorale qui permettent aux os de s'articuler correctement, d'assurer le mouvement.Le fémur : c'est l'os le plus fort et le plus long de tout notre corps, et à juste titre, car il fait non seulement partie de l'articulation de la hanche, mais aussi du genou. La tête fémorale est la zone de l'os qui fait partie de la hanche, qui s'encastre dans le cotyle pour faciliter le mouvement.

[venthop]

cotyle, a wildclaw m accent, is available for 400g!

[shaper-gato]

42"/ CELL CORE / 2 PRO / CRESCENT TAIL / / / #custom_boards #shaperbygato #handcrafted #bodyboardshaper #bodyboarding #bodyboard #bodyboards #bodyboarders #bodyboarder #madeinportugal... Photo number 3085 #custom to @milkbodyboards (em Refresh Boards) https://www.instagram.com/p/COTYl-jHX9-/?igshid=8x5n37o6rgil

[oistosocial-blog]

Zimmer 05CC56 ADES Cotyle Double Mobilite, Diameter 56

[augmentationmammaireparis]

Connaître l’augmentation mammaire

L'augmentation mammaire pure, l'augmentation mammaire avec lifting ainsi que le changement d'implant sont proposés. En raison de la spécialisation de plusieurs chirurgiens plasticiens dans le domaine de la chirurgie mammaire, vous avez un grand choix de médecins. Tous les médecins vous traiteront avec les méthodes les plus récentes et vous informeront en détail sur les implants coûteux.

Outre la taille des implants, la forme, la surface de base et la projection jouent un rôle dans l'obtention d'une poitrine parfaite. La zone de base de l'implant détermine le décolleté ultérieur. La projection et le volume de l'implant déterminent la taille ultérieure du cotyle.

Nous comprenons que le prix est surprenant au début. Mais nous sommes heureux d'expliquer en détail comment ce prix particulièrement bas est possible.

Tous les détails de cette offre peuvent également être téléchargés dans notre brochure au format PDF.

Nous avons résumé ici les questions les plus fréquemment posées.

Un bref résumé de la procédure :

Pour une augmentation mammaire, vous pouvez réserver votre consultation personnelle avec un spécialiste directement ici en ligne. Bien entendu, nous travaillons exclusivement pour des cliniques privées ou des cliniques avec des spécialistes de la chirurgie plastique et esthétique qui se sont spécialisés dans ces procédures. Ces derniers effectuent également la consultation pour la chirurgie mammaire.

Après avoir pris rendez-vous avec votre médecin à Paris, nous vous en informerons par courrier électronique. Au cours de cet entretien, vous clarifierez tous les détails avec le médecin. Vous pouvez également y organiser l'augmentation mammaire avec le médecin.

La consultation pour une augmentation mammaire ne vous engage à rien

La consultation que vous avez avec nos cliniques partenaires/médecins partenaires ne vous oblige pas à subir une opération ! C'est vous qui décidez si vous voulez ou non faire procéder à une augmentation mammaire. Vous devez poser toutes les questions que vous avez pendant la consultation. Si vous décidez ensuite de vous faire opérer, concluez le contrat d'augmentation mammaire directement avec le médecin. La consultation pour l'augmentation mammaire a lieu à Paris, l'intervention elle-même sera également réalisée à Paris. Le médecin avec lequel vous avez une consultation effectuera également l'opération. Nous ne travaillons que pour des cliniques privées où un grand nombre d'augmentations mammaires ont déjà été effectuées.

Avant d'envisager une augmentation mammaire à l'étranger, vous devez vous informer sur les risques possibles.

Vous trouverez ici des informations plus détaillées que nous mettons à votre disposition :

- Nous avons rassemblé ici les questions les plus fréquemment posées sur l'augmentation mammaire.

- Conseils généraux importants : À quoi devez-vous faire attention si vous souhaitez procéder à une augmentation mammaire ?

- Toutes les données et informations importantes se trouvent dans notre brochure

"On nous demande souvent comment il est possible d'obtenir un prix aussi bas pour une augmentation mammaire. Bien entendu, nous vous expliquerons cela en détail. L'opération ne se déroule en aucun cas à l'étranger - où, bien sûr, il y a aussi des offres extrêmement favorables.

Sites Internet à connaître

 1. https://www.riccardomarsili.fr/differentes-techniques-daugmentation-mammaire/

2. https://www.chirurgie-esthetique-vincent-masson.com/augmentation-mammaire-paris

[albertonykus]

Worthy et al. (2017) suggest that gastornithiforms lost flight more than once like palaeognaths did. If this is indeed the case, doesn't the case for gastornithiform monophyly fall apart like it did with "ratites"?

Why would it? According to the same study, the characters found to unite gastornithiforms are:

Premaxilla with straightventral margin

External aperture ofcarotid canal posterior to paroccipital notch

Mandibular process ofquadrate descends to meet ascending ramus of otic process in wide angle inlateral view

Coronoid region of mandiblemarkedly reduced

Short retroarticularprocess of mandible

Medial mandibularprocess not long, narrow, and dorsally oriented

No notches or fenestraealong caudal margin of sternum

Coracoid fused withscapula

Preacetabular region ofsynsacrum less than 40% total synsacral length

Distinct intertranversefenestrae present along length of pelvis posterior to acetabulum

Iliac recess of pelvisabsent

Pubis straight or flat(rather than dorsally concave)

An elevatedimpressiones obturatoriae of femur close to the facies articularisantitrochanterica and a large prominence further distally on the caudolateralmargin for m. ischiofemoralis

Insertion area of m.iliotrochantericus caudalis on dorsal margin of femur

Orientation of lateralcondyle of femur markedly divergent from axis

Tubercle for tuber. m.gastrocnemialis lateralis an elongate rugose scar in fossa, traversing caudalfacies of femur from lateral edge of the fibular trochlea of proximal end oftibiofibular crest

Medial condyle of femurmaximum distal width greater than half the femoral width

Popliteal fossa offemur deep

Impressio lig.collateralis medialis on tibiotarsus prominent

Pronounced medialepicondyle of tibiotarsus with internal ligamental prominence

Conspicuous scar forlig. collaterale medialis on tibiotarsus present but short

Impressio ligamentiintercondylaris on tibiotarsus extendes medially by excavation caudal to themedial condyle

Distinct flange-likeprocessus on plantarmedial edge of medial cotyle of tarsometatarsus

No proximal elevationof rim at the plantarolateral side of medial cotyle of tarsometatarsus

Two hypotarsal ridges

Anterior end of distalinterosseal canal of tarsometatarsus largely or completely exposed by reductionin bony covering

Intermediate phalangesof pedal digit IV shorten successively towards ungual, so that phalanx proximalto the latter is wider than long or nearly square in shape

Ungual phalanges ofpedal digit III wider than deep at midlength

Squamosal processussuprameaticus of cranium robust and conical with circular cross section andadpressed to cotyla quadratica oticum caudal to cotyla quadratica

Few if any of those features seem like they’re directly associated with flightlessness.

[chirurgieorthopediquemontpe-blog]

Quelles hanches nécessitent leur remplacement par une PTH ?

Chirurgie de la hanche - Orthopôle 34

Ce sont les hanches qui ont été détruites par des maladies ou des traumatismes et qui deviennent raides et douloureuses :

1-Arthrose de hanche (coxarthrose) liée à l’usure progressive du cartilage pour laquelle on retrouve de nombreux facteurs favorisants

le surpoids

les traumatismes, fractures du col ou de la tête fémorale, fracture du cotyle, luxations

les séquelles de maladies de l’enfance et les malformations congénitales comme la luxation congénitale, l’épiphysiolyse et l’ostéochondrite.

2-Maladies inflammatoires de hanche (arthrites) qui détruisent le cartilage et sont responsables de poussées douloureuses avec des épanchements articulaires.

Ces arthrites sont nombreuses : rhumatisme inflammatoire comme la maladie rhumatoïde, maladies liées à des cristaux dans le liquide articulaire comme la goutte et la chondrocalcinose, maladies de la membrane synoviale comme l’ostéochondromatose.

3-Ostéonécrose de la tête fémorale où un fragment de cartilage est dévascularisé et s’enfonce en supprimant l’harmonie de l’arrondi de la tête fémorale.

4-Les fractures du col fémoral sont souvent traitées aussi par PTH pour permettre la reprise rapide de la marche.

5-Certaines tumeurs du fémur proximal et du cotyle.

En savoir plus

[sauvesparlekong]

     De capricieux pétrels    Défroissent avec glamour Leurs graphitiques ailes Tandis que des mouettes      Australes et folkloriques        Défeuillent les zinnias          Amplement déployés.          Lui, singulièrement,        Du parterre siliceux    Observe avec ferveur Ces cotonneux oiseaux Qui tels des patineurs     Agitent élégamment        Leurs cotyles d'albâtre Beatrice Vigneaux - Sauvés par la Poésie 2019   #sauvesparlekong #sauvesparlapoesie #sauvespourlebac #revisionsbac #bacfrancais #baccalauréat #bacfrançais #bacrevisions #revisions #revisionsbac #tutoring #tutoringhk #onlinetutoring #onlinetutor #onlinetutorial #bacfrancais2019 #brevet #brevet2019 #sauvesparlequiz (à Cafe Grey Deluxe, 奕居) https://www.instagram.com/p/Bv9G5ADH4C8/?utm_source=ig_tumblr_share&igshid=1dgeminqztpby

[edufoleto-blog]

cotyléforo

cotyléforo

Significado de cotyléforo

adj.

Que tem cótylos.

[tunisie--esthetic]

Votre articulation de la hanche est formée par la tête fémorale et la partie de l'os du bassin qui la reçoit appelée le cotyle ou acétabulum. Ce cotyle fait partie intégrante de l'os iliaque.

Si les prothèses de la hanche et du genou sont les interventions les plus habituelles, le remplacement articulaire peut être réalisé dans d'autres articulations, la cheville, l'épaule, le coude … etc.

Les matériaux utilisés sont conçus pour restituer à l'articulation un mouvement aussi proche que possible de sa mécanique normale.

[azveille]

Orthopédie: modification des conditions d'inscription des cotyles

Le Journal officiel de mardi a publié un arrêté modifiant les conditions d'inscription des cotyles simple mobilité des prothèses de hanche sur la liste des produits et prestations (LPP), à compter du samedi 1er juin.

L'arrêté, qui est conforme à un avis de projet publié en octobre 2018 (cf dépêche du 30/10/2018 à 12:05), crée six nouveaux codes LPP pour les lignes génériques "cotyles standards modulaires", "cotyles de reconstruction" et "inserts seuls" (sous-rubriques "insert en polymère massif" et "insert en céramique").

Les produits correspondants sont pris en charge jusqu'au 31 juillet 2027 dans le cadre de la LPP. Ils sont aussi inscrits sur la liste en sus.

Les nouveaux codes vont remplacer six codes radiés de la LPP et de la liste en sus à partir du vendredi 31 mai.

Leurs tarifs et prix limites de vente (PLV), qui sont identiques, sont compris entre 83,06 euros et 902,38 euros TTC pour un cotyle simple mobilité ou un insert. Ils représentent des baisses de 1,3% à 4,5% par rapport aux tarifs associés aux anciens codes.

Les nouveaux tarifs ont fait l'objet d'une convention entre le Comité économique des produits de santé (CEPS) d'une part, et l'Association des fabricants importateurs distributeurs européens d'implants orthopédiques et traumatologiques (Afideo) et le Syndicat national de l'industrie des technologies médicales (Snitem), d'autre part.

Selon l'arrêté, une prothèse totale de hanche est composée d'une tige avec col; d'une tête indépendante de la tige (en cas de tige modulaire) ou non, en cas de tige monobloc ou de prothèse fémorale unipolaire monobloc; et d'un cotyle monobloc ou modulaire avec insert amovible.

Les cotyles simple mobilité ont un insert fixe par rapport au métal-back. Les inserts simple mobilité sont fixes par rapport au métal-back associé.

S'agissant des prothèses de hanche intermédiaires, elles sont composées d'une tige avec col, d'une tête et d'une cupule mobile qui exclut la pose d'un implant cotyloïdien.

[rbbox]

Aetiocetus

Aetiocetus

Aetiocetus is a genus of extinct basal mysticete, or baleen whale that lived 33.9 to 23.03 million years ago, in the late Oligocene in the North Pacific ocean, around Japan, Mexico, and Oregon, U.S. It was first described by Douglas Emlong in 1966 and currently contains known four species, A. cotylalveus, A. polydentatus, A. tomitai, and A. weltoni. These whales are remarkable for their retention of teeth and presence of nutrient foramina, indicating that they possessed baleen. Thus, Aetiocetus represents the transition from teeth to baleen in Oligocene mysticetes. Baleen is a highly derived character, or synapomorphy, of mysticetes, and is a keratinous structure that grows from the palate, or roof of the mouth, of the whale. The presence of baleen is inferred from the fossil record in the skull of Aetiocetus. Aetiocetus is known from both sides of the Pacific ocean: it was first documented in Oregon, United States, but it is also known from Japan and Mexico. The genus is currently constrained to the Northern hemisphere and has little value in biostratigraphic studies of the Oligocene due to its limited occurrences across the Pacific. Etymology Aetiocetus means “causal whale”, with aetio- being the Greek root for “cause” or “origin”, and –cetus meaning “whale”. This name was given to the genus by Douglas Emlong in his 1966 monograph of Aetiocetus cotylalveus, though he failed to present an etymology. A. cotylalveus approximately means “bowl cavity”, cotyl- meaning “cup” or “bowl” in Greek, while alveus is Latin for “hollow” or “cavity”. However, the author’s original reasoning for the genus and species name for A. cotylalveus remains unknown. A. tomitai is named in honor of then-mayor Akio Tomita of Ashoro-cho, Hokkaido, Japan, who was a huge support for their work on Japanese cetaceans. A. weltoni is named in honor of Doctor Bruce J. Welton, who initially discovered the holotype and directed the excavation of the skeleton. A. polydentatus is named in reference to the polydont dentition present in the specimen; poly- being the Greek root for “many” and –dentatus Latin for “toothed”. Geological and environmental context A. cotylalveus is known from the Yaquina Formation of Oregon. The Yaquina Formation is late Oligocene in age and at the cetacean’s locality consists of a fine-grained grey sandstone with alternating layers of medium-grained light-grey sandstone and siltstone. The Yaquina Formation represents a coastal marine depositional environment, and is considered late late Oligocene in age (Chattian) based on foraminifera and mollusc stages; approximately 24-25 million years in age. A. weltoni is also known from the Yaquina Formation and occurs along the same cliff face as A. cotylalveus, but occurs higher in the stratigraphic section. This specimen was found in situ near the contact of the conformably overlying Nye Formation, which is Miocene in age. Thus, A. weltoni is very close to the Oligocene-Miocene boundary. A. tomitai was discovered in the Middle Hard Shale member of the Morawan Formation, Kawakami group in Japan. This is also late Oligocene in age and represents a basinal depositional environment. This specimen was not found in situ, but in a loose concretion, and could potentially be stratigraphically higher than the Middle Hard Shale, but Barnes et al. presume that the animal was not transported far from the location where it died. A. polydentatus was also discovered in the Morawan Formation of Japan, but from the Upper Tuffaceous Siltstone Member, which also represents a basinal depositional environment. The holotype was found in situ in the uppermost part of the member. It is currently the stratigraphically highest occurrence of an aetiocetid from the northwestern Pacific Ocean, meaning that it is the youngest known specimen of Aetiocetus. Discovery and history Aetiocetus cotylalveus was discovered in 1966 and described by Emlong, who initially ascribed Aetiocetus to the Archaeoceti based on its plesiomorphic, or primitive, dentition; he felt that the presence of teeth barred Aetiocetus from the Mysticeti. There are many distinct features that separates Aetiocetus from Odontoceti, or toothed whales, and Emlong did not see evidence of remodeling necessary for the modern odontocete skull. Notably, Emlong noted that Aetiocetus was some antecedent to the mysticete lineage, due to the degree of telescoping on the skull, indicating that the nostrils of the whale had migrated further back on the skull than seen in archaeocetes. Along with the relation between cranial features, Emlong allied Aetiocetus more closely with Mysticeti than Odontoceti. However, as A. cotylalveus retains teeth, Emlong considered it a highly derived archeocete. Van Valen in his 1968 essay “Monophyly or diphyly in the origin of whales” placed Aetiocetus in its accepted position as a basal, or early, mysticete. In 1995, Lawrence G. Barnes and his co-authors Masaichi Kimura, Hitoshi Furusawa, and Hiroshi Sawamura described three new aetiocetids that allied with the genus Aetiocetus. These finds were unique in that they placed an aetiocetid within the same geologic formation as the type specimen, A. cotylalveus, and also placed new aetiocetids on the western coast of the Pacific, in Japan. This extended the geographic range of Aetiocetus dramatically. In 1998, L.G. Barnes listed a specimen of Aetiocetus within his list of fossil marine mammal assemblages in Mexico. However, this specimen remains aff. Aetiocetus sp., and cannot be ascribed to any particular species. This specimen was found in Baja California in the El Cien Formation, but as of yet no paper has been published describing this specimen. Description The type species for the genus is Aetiocetus cotylalveus. It is defined as being the monophyletic group encompassing the closest common ancestor of A. cotylalveus and A. polydentatus and all its descendants: the textbook definition for a monophyletic taxon. Aetiocetus is a small, toothed whale with no more than three small denticles on the anterior and posterior margins of the posterior upper teeth. Their postcanine teeth are somewhat heterodont. The base of the rostrum, or snout, of the whale, is greater than 170% of the width of the occipital condyles where the skull meets the neck. These features are synapomorphies, or shared derived traits, of Aetiocetus. There is a distinct notch by the internal nostrils formed of the palatine, pterygoid, and vomer bones; this is a synapomorphy of Aetiocetus + Chonecetus. Synapomorphies of the aetiocetids present in Aetiocetus are: the coronoid process of the dentary, or lower jaw, is well developed; the zygomatic arch is expanded anteriorly and posteriorly but is narrow at the middle. Aetiocetus also shares several traits with all mysticetes. The mandibular symphysis, or the connection between both lower jaw bones, is not fused. The descending process of the maxilla becomes a toothless plate below the orbit. They possess a wide rostrum. All these features are functionally related to filter-feeding with baleen and is a hallmark of the Mysticeti. The presence of teeth, as Barnes et al. remark, seems paradoxical. Lastly, Aetiocetus shows some symplesiomorphic traits with more archaic whales. The do not experience the same degree of telescoping as modern whales, so their nares, or nostrils, are still relatively anterior. Contrary to the image of the modern baleen whales, Aetiocetus still possessed developed, enamelized adult teeth . This indicates that loss of functionality in relevant enamel genes, such as ameloblastin (AMBN), enamelin (ENAM), and amelogenin (AMEL), had not yet taken place in Aetiocetus. For the most part, Aetiocetus retains a primitive tooth count of 11 upper teeth and 11 lower teeth, abbreviated 11/11. This is interpreted to be the basic mammalian dental formula with 3 incisors, 1 canine, 4 premolars, and 3 molars on both upper and lower jaws. However, A. weltoni and A. polydentatus show variation from the plesiomorphic mammalian dental formula. A. weltoni possesses a 11/12 dentition. True to its name of “many toothed”, A. polydentatus possesses more teeth than any other aetiocetid, and is remarkable in that the number of teeth are asymmetrical. On the right side of the upper jaw, A. polydentatus has 13 teeth, and on the left it has 14 teeth. The bottom jaw is also asymmetric, with 14 teeth in the right dentary and 15 in the left. This is the first polydont aetiocetid, meaning that it had more teeth than the standard mammalian formula. Embryonic baleen whales have polydont teeth before birth. A. polydentatus indicates that this condition was also present in tooth-bearing mysticetes, as expected from developmental data. In addition to its polydont dentition, A. polydentatus is unique in that these teeth are not differentiated into different teeth types as seen in other members of Aetiocetus. Paleontologists refer to this condition as being homodont, or “same tooth”. Aetiocetus is unique in its representation of transition from toothed archaeocete to toothless mysticete. It is important, however, to make the distinction that Aetiocetus is not a transitional form in the strictest sense, that is, it cannot be an ancestor to extant Mysticeti. More derived forms, such the Cetotheriidae, a family of toothless baleen whales, are contemporaneous with Aetiocetus. Hence, whales whose feeding relied entirely on baleen made their stratigraphic appearance before Aetiocetus, meaning that “true” baleen whales existed before Aetiocetus. Baleen is made of keratin (the same material that comprises claws, hooves, nails, and hair) that grows throughout the whale’s life. Development of mysticetes indicate that they had a toothed ancestor, as the fetal baleen whale forms tooth buds which are later reabsorbed and do not develop any further. However, Aetiocetus presents the evolutionary biologist with evidence for this transition in the fossil record. While baleen, as a soft tissue, does not preserve in the fossil record, whale paleontologists are able to identify evidence for baleen attachment in the palates of mysticetes. These are evident in what are known as nutrient foramina. These nutrient foramina, present on the maxillae of the whale, are associated with grooves and sulci, or fissures, which in life are occupied by branches of the superior alveolar artery and nerve. This superior alveolar artery supplies nutrients to the epithelial, or surface cells of the body, from which the baleen continuously develops. In all known archaeocetes and odontocetes, nutrient foramina are absent. These nutrient foramina are most apparent in A. weltoni, whose holotype has the best-preserved palate. The development of nutrient foramina and teeth are closely intertwined in mysticetes: first, an alveolar groove on the palate of the developing mysticete. The deciduous teeth form in the groove, and then are reabsorbed, while development of rudimentary baleen plates begin. The alveolar groove fills with bone until the laterial nutrient foramina form. This close association leads Demere and Berta to hypothesize that Aetiocetus displays an ancient ontogeny, or growth sequence. These nutrient foramina are also present on Aetiocetus cotylalveus and another related aetiocetid, Chonecetus goedertorum. Compared to other edentulous, or toothless, mysticetes, the pattern of nutrient foramina is most similar to extant balaenopterids (blue whales and other rorquals) and fossil cetotheres. Schematic of the bulk feeding method employed by modern mysticetes. It is plausible that Aetiocetus used a variation of this method using a combination of baleen and teeth. How did Aetiocetus feed, and what did it feed on? Its teeth are reminiscent of the bite-and-swallow strategy of archaeocetes and odontocetes, but they also possessed expanded palates. Modern mysticetes grow their baleen from this expanded palate and use the baleen to trap arthropods and fish in their mouths. This is known as bulk-feeding, in that the whale is not selecting individual prey items and does not use echolocation to find prey, as odontocetes do. Fossil mysticetes with wide, toothless palates are inferred to bulk-feed and the first occurrence of such whales is in the late Oligocene, approximately 4 to 5 million years after the first toothless mysticetes appeared. A crucial question is, then, did Aetiocetus feed by bulk-feeding or by bite-and-swallow? If they fed only by selective prey capture, were they simply pre-adapted for the specialized feeding behavior of extant mysticetes? Structurally, Aetiocetus possesses teeth that are quite similar to primitive odontocetes, such as Squalodon. These odontocetes have an inferred bite and tear style of eating with limited mastication. Both primitive and extant odontocetes find their prey through the use of echolocation; however, mysticetes have no evidence in their fossil record of ever evolving or initially possessing the ability to echolocate. Piscivory, or a diet based solely on fish, is likely the primitive condition for Cetacea, and it seems most parsimonious that Aetiocetus fed like an archaeocete, locating fish without the use of echolocation. However, an argument exists that Aetiocetus was in fact a bulk feeder, who fed by gulping and straining prey from the water through their interlocking cusped cheek teeth. This is supported by the presence of a lack of mandibular symphysis, meaning the jaw was loosely articulated, and by the presence of the wide palate. This feeding method has an analog in crab-eater seals. This hypothesis combines the idea of bulk feeding and retention of the dentition. Aetiocetus might have been a functional mysticete. Lending credence to this interpretation is the presence of mandibular kinesis in Aetiocetus, though they lack the rostral kinesis seen in more derived mysticetes. This cranial kinesis, or ability of the skull bones to move relative to one another, permit the mysticete skull to decrease the strain exerted on the skull during bulk feeding. Fitzgerald argued against the model of tooth-aided filter feeding, based on the lack of closely pressed teeth and the presence of simple postcanine crowns. Deméré argues that this assumes a very small prey size (i.e., krill). The distinction here is that Aetiocetus was a bulk feeder, and prey size does not enter into this definition of feeding strategy. There is no reason to assume a priori that all bulk filter-feeders eat small prey, given the large diversity of food items consumed by modern mysticetes. Demere hypothesizes that Aetiocetus’ bulk feeding behavior could have targeted large prey, such as schooling fish or squid. With prey items of this size, Aetiocetus’ teeth would still have served well as a coarse sieve. At first glance, the fact that species are known from only one locality, and that may suggest that Aetiocetus was highly endemic. Deméré and Berta consider Aetiocetus to be a lineage endemic to the north Pacific ocean basin. High endemism would be highly atypical of mysticetes. However, a more likely explanation is that the fossil record for Aetiocetus is poor, or that a sampling bias is present and not enough work has been done in late Oligocene deposits in the south Pacific ocean. Perhaps there are more specimens of Aetiocetus that will be discovered as paleontologists continue searching. The other genera in the family Aetiocetidae are Ashorocetus, Chonecetus, Morawanocetus, and Willungacetus. All aetiocetids are known from the North Pacific except the Australian Willungacetus and its taxonomy is disputed. Dentition For the most part, Aetiocetus retains a primitive tooth count of 11 upper teeth and 11 lower teeth, abbreviated 11/11. This is interpreted to be the basic mammalian dental formula with 3 incisors, 1 canine, 4 premolars, and 3 molars on both upper and lower jaws. However, A. weltoni and A. polydentatus show variation from the plesiomorphic mammalian dental formula. A. weltoni possesses a 11/12 dentition. True to its name of “many toothed”, A. polydentatus possesses more teeth than any other aetiocetid, and is remarkable in that the number of teeth are asymmetrical. On the right side of the upper jaw, A. polydentatus has 13 teeth, and on the left it has 14 teeth. The bottom jaw is also asymmetric, with 14 teeth in the right dentary and 15 in the left. This is the first polydont aetiocetid, meaning that it had more teeth than the standard mammalian formula. Embryonic baleen whales have polydont teeth before birth. A. polydentatus indicates that this condition was also present in tooth-bearing mysticetes, as expected from developmental data. In addition to its polydont dentition, A. polydentatus is unique in that these teeth are not differentiated into different teeth types as seen in other members of Aetiocetus. Paleontologists refer to this condition as being homodont, or “same tooth”. Phylogenetic context There has been some dispute about the relationships between Aetiocetus and its relationship to stem Mysticetes. Barnes et al. (1995) expanded Emlong’s original definition to encompass eight species in four genera. They suggested a monophyletic Aetiocetidae with three subfamilies: Chonecetinae, which includes Chonecetus spp., Morawanocetinae, which includes Morawanocetus yabukii, and Aetiocetinae, which contains Ashorocetus eguchii and Aetiocetus spp. In 2002, Sanders and Barnes hypothesized that there was a larger superfamily, Aetiocetoidea, which would include all known toothed mysticetes: Aetiocetidae, Llanocetidae, and Mammalodontidae. However, evidence suggests that this “Aetiocetoidea” is a grade taxon and does not actually form a natural group, as the retention of teeth is a symplesiomorphic condition for Cetacea and cannot be used as a synapomorphy for the group. Fitzgerald in 2006 proposed 6 major toothed mysticete lineages, in which Aetiocetidae was paraphyletic, with a Chonocetus clade and an Aetiocetus clade. A. polydentatus was considered by Fitzgerald to not be a member of Aetiocetus at all because of its seemingly derived features in comparison to other members of the Aetiocetus genus, for instance, its polydont dentition and greatly enlarged nasal bones. The debate regarding relationships within the Aetiocetidae highlight the importance of this clade to the understanding of basal mysticete evolution and hypotheses surrounding the loss of adult teeth and the development of baleen. The larger scale phylogenetic placement of Aetiocetus has remained fairly constant throughout modern studies. Geisler and Sanders’ 2003 paper, “Morphological Evidence for the Phylogeny of Cetacea” used the genus in their morphological cladistics study and their results support a monophyletic Aetiocetidae (Aetiocetus + Chonecetus). Here, the Aetiocetidae is the sister taxon to Eomysticetus+ Micromysticetus + Diorocetus + Pelocetus + crown Mysticeti. In their sample, Aetiocetus is the second-most basal mysticete; two undescribed museum specimens, ChM, are considered the most basal mysticetes in this phylogeny. In Geisler et al.’s 2011 study entitled “A supermatrix analysis of genomic, morphological, and paleontological data from crown Cetacea”, there is higher resolution of Aetiocetus’ phylogenetic relationship with other mysticetes, as well as more taxa considered. In this study, Aetiocetus is still basal and is still the sister taxon to Eomysticetus + Micromysticetus + Diorocetus + Pelocetus + crown Mysticeti, all of which possess baleen and no teeth. It is interesting to note that there are two competing hypotheses supported by the supermatrix: 1) that Aetiocetus is not the sister group to Chonecetus, suggesting that the Aetiocetidae is a paraphyletic group, an group in which not all descendants are considered, or 2) that they indeed form a monophyletic group. Both results have been supported in previous studies. In an even more recent paper, entitled “A Phylogenetic Blueprint for a Modern Whale”, more than one species in the genus Aetiocetus is used: A. cotylalveus, A. weltoni, and A. polydentatus. These three taxa form a polytomy with Chonecetus, where the relationships of the four taxa cannot be more determined with the present resolution. However, this result suggests monophyly of the Aetiocetidae, or that all aetiocetids are derived from a single common ancestor. In this phylogeny, the Aetiocetidae is the sister taxon to Eomysticetus + Cetotheriidae + crown Mysticeti. Almost all phylogenies agree that Aetiocetus is a stem mysticete with no affiliation with crown Mysticeti. This result is not entirely surprising, given its symplesiomorphic condition, meaning that Aetiocetus still retains many primitive features and few derived ones. Its phylogenetic placement among stem mysticetes is also in line with its late Oligocene stratigraphic occurrence, where crown Mysticeti had yet to appear in the fossil record. source - Wikipedia Dear friends, if you liked our post, please do not forget to share and comment like this. If you want to share your information with us, please send us your post with your name and photo at RBbox.in@gmail.com. We will publish your post with your name and photo. thanks for joining us www.rbbox.in

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050-Cotyle riparia. Sand-Martin - high resolution image from old book.