Conodonts are Cambrian to Late Triassic marine vertebrates
most often known for their tiny complex, multicusped tooth sets (video 1, Fig. 2). These hydroxyapatite (crystalline calcium phosphate) teeth appear prior to the genesis of jaws and enamel teeth arising from the premaxilla, maxilla and dentary in basal sharks, like the nurse shark, Ginglymostoma and arising from epidermal denticles ( = shark skin).
Tooth enamel = Ca10(PO4)6-2(OH)
Hydroxyapatite = Ca5(PO4)3(OH)
Conodont teeth grow on the eversible tongue,
lips, cheeks and other oral layers, somewhat in the manner of nematodes and hagfish (Fig. 1), from which they phylogenetically descend in the large reptile tree (LRT, 1885+ taxa) and elsewhere (e.g. Goudemand et al. 2011). The tooth set in video 1 is from Novipathodus from the Earliest Triassic. It is much smaller, younger, and much more complex than the tooth set in a simpler conodont from the Late Ordovician, Promissum (Fig. 2).
According the Goudemand, et al. 2011,
Novispathodus belongs to the more derived conodont clade, Ozarkodontinina. Promissum belongs to a more basal conodont clade, Balaognathidae.
From the Goudemand, et al. 2011 abstract,
“The origin of jaws remains largely an enigma that is best addressed by studying fossil and living jawless vertebrates.”
The LRT indicates this is false. Conodonts and living jawless vertebrates provide no clue to the origin of jaws. In phylogenetic analysis, as demonstrated by the LRT, toothless jaws originated in the Ordovician with shark-like Chondrosteus and Strongylosteus. These were derived from tube-feeding sturgeons, which provide the only fossil and living clues to the origin of jaws.
Only a few conodont fossils preserve soft tissue
and those few that do can have enormous eyeballs, lamprey-like gill openings, an anteroventral mouth, a long body and only one fin at the tail tip. Gabbott, Aldridge and Theron 1995 considered Promissum (Fig. 2) a ‘giant conodont.’ at an estimated 40cm. It has 19 denticulated elements (Fig. 2) and relatively smaller eyeballs.
Traditionally conodont teeth,
ranging in size from 0.2mm to 5mm in length, were all that was known of these primitive and ancient worm-like fish. Conodont teeth are found in complex sets of often scattered elements forming an apparatus when reassembled. How they went together and operated as a unit was first animated by Goudemand et al. 2011 (video 1), and good work on that previously intractable problem!
According to Goudemand, et al.,
“Fused clusters partially preserve the relative 3D positions and orientations of the involved elements. However, they are very small, fragile, tricky to manipulate, and if more than two or three elements are involved, very complicated to analyze.” Too small for X-ray microtomography, the authors used, “submicron resolution propagation phasecontrast X-ray synchrotron microtomography.”
According to Wikipedia,
“The “teeth” of some conodonts have been interpreted as filter-feeding apparatuses, filtering plankton from the water and passing it down the throat. Others have been interpreted as a “grasping and crushing array”.
By contrast, Jones et al. 2012 concluded,
“we show that their morphology is adapted to overcome size limitations by developing dental tools of unparalleled sharpness which maximize applied stress.”
Another, cruder, cheaper animation of another conodont aparatus
is presented for Promissum pulchrum of the Late Ordovician (Fig. 2). Note the major differences between these elements and those of the more complex Triassic conodont, Novispathodus (video 1). The prey menu available in the late Ordovician was different and so were the defenses protecting prey items from conodont attacks.
Goudemand et al. 2011 reported,
“Due to the comparative feeding mechanism and other similarities, lampreys and conodonts must have a common ancestor which was one of the first vertebrates. This common ancestor must also have had a tongue mounted on pulley-like cartilage and therefore eaten in the same manner as the conodonts.”
No surprise. That last common ancestor was the hagfish, Myxine (Fig. 1) in the LRT and in other published studies (e.g. Goudemand et al. 2011).
Conodonts are not found in Jurassic rocks
They became extinct at the very end of the Triassic.
Gabbott SE, Aldridge RJ and Theron JN 1995. A giant conodont with preserved muscle tissue from the Upper Ordovician of South Africa. Nature 374(27):800–803.
Goudemand N et al. (4 co-authors) 2011. Synchrotron-aided reconstruction of the conodont feeding apparatus and implications for the mouth of the first vertebrates. Proceedings of the National Academy of Sciences, 2011; DOI: 10.1073/pnas.1101754108
Jones D et al. (4 co-authors) 2912. The sharpest tools in the box? Quantitative analysis of conodont element functional morphology. Proceedings of the Royal Society B 279(1739): https://doi.org/10.1098/rspb.2012.0147
University of Zurich. “Peculiar feeding mechanism of the first vertebrates.” ScienceDaily. ScienceDaily, 20 May 2011.
Please Help Support BeforeitsNews by trying our Natural Health Products below!
Order by Phone at 888-809-8385 or online at https://mitocopper.com M - F 9am to 5pm EST
Order by Phone at 888-388-7003 or online at https://www.herbanomic.com M - F 9am to 5pm EST
Order by Phone at 888-388-7003 or online at https://www.herbanomics.com M - F 9am to 5pm EST
Humic & Fulvic Trace Minerals Complex - Nature's most important supplement! Vivid Dreams again!
HNEX HydroNano EXtracellular Water - Improve immune system health and reduce inflammation
Ultimate Clinical Potency Curcumin - Natural pain relief, reduce inflammation and so much more.
Oxy Powder - Natural Colon Cleanser! Cleans out toxic buildup with oxygen!
Nascent Iodine - Promotes detoxification, mental focus and thyroid health.
Smart Meter Cover - Reduces Smart Meter radiation by 96%! (See Video)