Eurasian 250 Mio years old marine reptiles – shell eaters or algae vegetarians

Eurasian 250 Mio years old marine reptiles – shell eaters or algae vegetarians



Author: Cajus G. Diedrich

While many researchers still insist: “Triassic reptiles to be shell eaters”, even in youngest cladist oriented and not convincing articles published in Paleo 3 journals of 2014, whereas at the same time modern dugong researchers underline in 2014 the theory such as a large study about “placodonts marine reptiles” (= Triassic Sea Cows) with new articles in 2013: around 240 Mio years ago large populations were “vegetarians” – and not “shell eaters”.

In Cajus Diedrich’ s research review from the independent Research Institute PaleoLogic, published in Natural Science  2011 vol.1, no. 1 by Scientific Research Publishing, the results were underlined again and again – being censored in many journals due to politics – and not logical arguments – in the past years with several interdisciplinary studies about the marine environments of the Triassic times, especially in Europe –including parts of China.

Classical and bone-oriented palaeontologists from all over the world – still insist, that “large “crushing teeth” in all groups of vertebrates are/were used for cracking hard prey – which is as we know from comparisons to modern animals, especially mammals and even reptiles incorrect. Further funny comments made on the publication of Diedrich were: citation: “cows can rotate the jaw in the jounts and can chew grass – seacows can not” – exactly, this contradictionary “argument” explains the jaw function. Nor seacows or placodonts reptiles “chew/chewed” – they squeeze the vegetarian food without “chewing”.

Sea shells were suggested in former times and again in “newer research” to have been eaten in “mass” by such extinct marine “nut cracking jaw type” reptiles – but: 1. there is no skeleton found in the world with shell contents in its stomach (even not in a Chinese Placodus skeleton), 2. first enamel microscope scans do not show intensive abrasion of the teeth and scratched seem to come from sand – proving even the digging of the complete seaplants inclusive its roots (similar as in modern sirenians), 3. is the jaw function best to compare with convergent evolved sirenians, and not to “nut crackers”, 4. is the anatomy of bone enhancement, extremity reduction completely similar convergent developed in both – placodonts (especially Placodus) and sirenians (e.g. Dugong).

Who is eating in those 240 Mio years past days “larger amounts of shells” no-one – compared today: indeed there are two marine mammals eating seashells: 1. sea otter – but he is that “clever” to use stones to crush the shells, but those only as a “desert” and not as main food, b. whale ruses – which are the only comparable large mammals – but, those are also “clever” not to have a full stomach with cutting edged shell fragments – those developed a suckling mechanism to extract the soft tissues leaving the valves intact on the sea floor.

None of any animal on planet Earth eats shells in large amounts – and if – not by “crushing shells in dangerous pieces”. Suggestions, that the extinct palcodont reptiles spilled fragments from their mouth do not fit to the jaw mechanism at all, nor to the dentition. E.g. the front teeth of Placodus have 5 mm spaces – quite unpractical to scratch shells from the seafloor –which get stuck in-between. The polish of the front teeth clearly prove “digging in the sand”. Striping of plants is nothing unusual – also in the “Triassic Park” times – even the largest dinosaur developed similar “pin-like” anterior teeth – to stripe off leaves/needles from branches.

Macroalgae – which were covering large seafloor areas along the 240 Mio aged Triassic southern Pangaea world landmass only in some regions correlate to the occurrence of larger placodont (sea cow) populations. In lagoons (= black shale oil facies) placodonts are rare with their fossils (e.g. China, Switzerland/Italy) – but the European intracratonic Germanic Basin – which was even under tsunami danger time by time, which is perfectly studied in its marine environments and beaches – has shallow marine 1-15 meters water depth) warm water conditions in many areas – comparable to modern sirenian carbonate mud/sand seafloor regions – such as found today similar in the Arabian Gulf – where about 7.000 dugongs come every year to feed and to reproduce.

Until today, neither logical arguments nor analogs in the living world were discussed by the “conservative palaeontologist” yet – that placodonts were simply the convergent “sea cows”, living in larger populations only in macroalgae-rich regions – seagrass was not developed at that time, to which later sirenians adapted to.

Algae were clearly already on the “menu” of reptiles – and still today in modern marine mammals – and became a delicates in “land mammals = humans. Possibly those, which are against the “plant eating theory” should consume larger amounts of seashells – but by crushing their valves – which would be a good, but bloody experiment. “Clever” humans eat the shells different.