Guess what these young dinosaurs ate when their parents weren't looking

Guess what these young dinosaurs ate when their parents weren't looking
Skeletal reconstruction of CMC VP14128 to scale with a mature D. carnegii (dark grey). Grey bones are missing, while those in ivory are those present in CMC VP14128. Skeletal reconstruction based on the Diplodocus by S. Hartman. Silhouettes by S. Hartman and PhyloPic, modifications made. Skeletal reconstruction of CMC VP14128 redrawn from D. carnegii skeletal by S. Hartman. Human scale is Andrew Carnegie at his natural height of 1.6 m. Skeletal and silhouettes to scale. (B) CMC VP14128 in right lateral view with accompanying schematic. (C) CMC VP14128 in left lateral view with accompanying schematic. Schematics by DCW. The four portions of the skull numbered on accompanying schematics. Lateral views and schematics to scale. a: angular, al: alisphenoid, aof: antorbital fenestra, d: dentary, f: frontal, h: hyoid, l: lacrimal, m: maxilla, n: nasal, oc: occipital condyle, os: orbitosphenoid, p: parietal, paof: preantorbital fenestra, pf: prefrontal, pm: premaxilla, po: postorbital, pro: prootic, q: quadrate, sa: surangular, sq: squamosal. L and r before bone denotes if it is left or right. Credit: Scientific Reports (2018). DOI: 10.1038/s41598-018-32620-x

Imagine a crew of hungry toddlers and kindergartners with unrestricted access to the kitchen. Would they gorge themselves on candy, chips and ice cream?

For a type of fast-growing youngster that lived 150 million years ago, the answer instead was a diverse, nutritious diet, rich in tender greens.

That finding resulted from the discovery, announced Thursday, of a rare juvenile dinosaur belonging to one of those familiar, long-necked plant-eaters called . Unlike adults of this particular species, called Diplodocus, the young dinosaur had two different kinds of teeth—pencil-like teeth in the front, and flatter, spatulalike chompers in the back.

The dino's dental diversity and narrow snout allowed it both to pick out the choicest shoots and chew them to extract as many nutrients as possible, said lead study author D. Cary Woodruff, a Ph.D. student at the Royal Ontario Museum and the University of Toronto.

Proper nutrition would have been essential to fuel fast growth for the animals, which hatched from a cantaloupe-size egg and reached a staggering 60 feet in length by the time they were teenagers, he said.

"We're thinking of it like a mouth with a Swiss Army knife," Woodruff said.

Adults, on the other hand, had only the pencil-like front teeth, set in a wider, vacuum-shaped snout, suggesting they raked up vegetation indiscriminately and swallowed it without chewing, said Woodruff, who collaborated with researchers from Princeton University and the Cincinnati Museum Center, among other institutions. And given their different diets, adult and juvenile sauropods likely were eating apart from one another, Woodruff and his coauthors wrote in the journal Scientific Reports.

Peter Dodson, a prominent University of Pennsylvania dinosaur expert who was not involved with the research, said the skull was an important find. He agreed that the young dinosaur's two kinds of teeth would have enabled the animal to feed itself—coupled with a narrow snout for selective extraction of the most tender, easy-to-digest plants.

Good thing, because if young sauropods had relied on their massive, 100-foot-long parents for handouts, they would have been in danger, said Dodson, a professor in Penn's School of Veterinary Medicine as well as its department of earth and environmental science.

"It seems like a pretty fair bet that there wasn't parental care," he said. "They could've been stepped on without the parent knowing it."

Dinosaur-hunters get excited when they find a sauropod skull, as the bones from the heads of these massive animals were delicate and often did not survive the ravages of time. As a result, many museum skeletons of Diplodocus and other sauropods are completed with a cast from the skull of a different dinosaur—sometimes not even the same species.

The skull Woodruff analyzed—found in a Montana quarry by study coauthor Glenn Storrs, of the Cincinnati Museum Center—is especially unusual for its completeness and the fact that it came from such a young animal.

Woodruff estimated that the creature was 2 to 4 years old when it died. Even at that tender age, its skull was already 9 inches long, with a body stretching at least 15 feet from head to tail.

Explore further

Dinosaur skull changed shape during growth

More information: D. Cary Woodruff et al. The Smallest Diplodocid Skull Reveals Cranial Ontogeny and Growth-Related Dietary Changes in the Largest Dinosaurs, Scientific Reports (2018). DOI: 10.1038/s41598-018-32620-x
Journal information: Scientific Reports

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Oct 13, 2018
Well, to be fair, the Creator did make all creatures to be vegetarians in the beginning:
Genesis 1:29-31.
It was only after the fall of mankind and the world wide flood that He allowed them to eat animals and other things. Hence of course also why He then made the other creatures fearful of mankind so that they could survive.
Genesis 9:2-3
2 And the fear of you and the dread of you shall be upon every beast of the earth, and upon every fowl of the air, upon all that moveth upon the earth, and upon all the fishes of the sea; into your hand are they delivered.

3 Every moving thing that liveth shall be meat for you; even as the green herb have I given you all things.

Oct 13, 2018
Yeah fred except that he gave many of them fangs and claws, not very useful for chasing down and disembowling fruits and veggies. Why would your creator give pacificists weapons of war?

"18 I also said to myself, "As for humans, God tests them so that they may see that they are like the animals. 19 Surely the fate of human beings is like that of the animals; the same fate awaits them both: As one dies, so dies the other."

-Or were lions and wolves created fangless and clawless and only grew these things after the fall? Were their bodies originally designed with muscles and metabolisms and digestive systems suitable for grazing instead of hunting?

Conversely were grazers originally designed without the ability to outrun predators, without horns and hooves and quills and stink sacs?

Assuming that your creator is an efficient designer who doesnt include extraneous elements in his creations, the pre-fall animals must've been completely different and unrecognizable animals.

Oct 13, 2018
"Well, to be fair" followed by an erroneous, irrelevant claim without peer review support.

For the record, we now know from the Planck latest data release that the universe is 100 % mechanistic - objects and processes - for sure, meaning 0 % 'creators'. Which ties in with that we know life evolved from alkaline hydrothermal vents, as discovered by phylogenies already 2016.
[Planck Legacy Archive; https://www.ncbi....27562259 ]

Astrology, religion, homeopathy, ... they are still peddling that?

Oct 14, 2018
fred. fred. fred. oh freddieboy! Have you no shame? No honor? Any ability to see yourself as as others do?

To blatantly steal from older religions and then screw up.
Not only with your incompetently translation of ancient scriptures.

But also with deliberate forethought, misinterpreting those Sumerian and Egyptian and Zoroastrian-Iranian scriptures you have so dishonestly plagiarize.

fred, since you fail to practice any of the moral pieties you claim a monopoly on? Why should anyone believe your self-serving falsehoods?

Oct 15, 2018
Well, to be fair, the Creator did make . . .

"Fair" doesn't apply to myths, fantasies, or hoaxes, of which all three describe this "creator."

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