© Julius CsotonyiIllustration of Massospondylus eggs and young dinosaurs.
A study of the world's earliest known dinosaur eggs reveals new information about the evolution of dinosaur reproduction.An international team of researchers led by Robert Reisz of the Department of Biology at the University of Toronto Mississauga studied the fossilized remains of eggs and eggshells discovered at sites in Argentina, China and South Africa-widely separated regions of the supercontinent Pangea. At 195 million years old, they are the earliest known eggs in the fossil record, and they were all laid by a group of stem sauropods-long-necked herbivores that ranged in size from four to eight metres in length and were the most common and widely spread dinosaurs of their time.
Reisz is puzzled by the fact that "reptile and mammal precursors appear as skeletons in the fossil record starting 316 million years ago, yet we know nothing of their eggs and eggshells until 120 million years later. It's a great mystery that eggs suddenly show up at this point, but not earlier."
According to Koen Stein, a post-doctoral researcher at Universiteit Gent and lead author of the project, the eggs represent a significant step in the evolution of dinosaur reproduction. Spherical, and about the size of a goose egg, these dinosaur eggshells were paper-thin and brittle, much thinner than similar-sized eggs of living birds."We know that these early eggs had hard shells because during fossilization they cracked and broke, but the shell pieces retained their original curvature."
© University of Toronto MississaugaFossilized dinosaur embryo
Members of the team, including Edina Prondvai and Jean-Marc Baele, analyzed shell thickness, membrane, mineral content and distribution of pores, looking for clues about why these early eggs might have developed hard shells. The results of the study show that hard-shelled eggs evolved early in dinosaur evolution with thickening occurring independently in several groups, but a few million years later other reptiles also developed hard-shelled eggs. One possibility is that hard and eventually thicker shells may have evolved to shield fetal dinosaurs and other reptiles from predators. "The hard shells would protect the embryos from invertebrates that could burrow into the buried egg nests and destroy them," says Reisz.
© R. David MazierskiReconstruction of a basal sauropodomorph egg showing detail of the eggshell. Eggshell units (esu) form the calcareous layer (cl) and are embedded with organic cores in the eggshell membrane (em).
Reisz adds that the study raises interesting questions for future investigation. "For example, we would like to understand why dinosaurs and their avian descendants never developed viviparity (live birth) and continued to rely on egg laying, while non dinosaurian reptiles and mammals, including ancient aquatic reptiles succeeded in evolving this more advanced reproductive strategy."
The study is co-authored by Koen Stein and Edina Prondvai (Universiteit Gent), Timothy Huang (Jilin University), Jean-Marc Baele (Université de Mons) and P. Martin Sander (Universität Bonn) and is published in the journal
Scientific Reports. It follows up on earlier research by Reisz,
published in 2012, that examined nests of Massospondylus embryos in eggs discovered at nesting sites in South Africa, and a 2013 publication on dinosaur embryology in Lufengosaurus from China.
Journal Reference:Koen Stein et al. "Structure and evolutionary implications of the earliest (Sinemurian, Early Jurassic) dinosaur eggs and eggshells",
Scientific Reports (2019).
DOI: 10.1038/s41598-019-40604-8
A fragmented and distorted 'point of view' or perceptual experience is a development of consciousness along the idea of A mind as 'doer' or power unto itself that is the idea of power struggle or conflicted and polarised differentiation and exclusion.
The fact that dinosaurs are uncovered with traces of flesh suggests to me that our projected timescale of millions of years, is a distortion - along with cave art showing dinosaurs alongside humans - and footprints of both in the same strata of petrified mud. Millions of years of gradual uniform change is a religion in which what a current perspective is projected backwards in a framing that accords new speciation to more time than we can relate to when I sense the opposite is true.
The anti-God idea is partly because the God idea has been so abused or corrupted by Church and State. But the things that were supposed to have been left behind by an enlightenment or rebirth now run as the corporate-cartel owned state that uses the mask of science as a church of consensual dogma. In other words it is the 'deceiver' that 'evolve's ever new ways to hide in what seems true and shut out the light in which a lie cannot abide.
The God Idea is at the root of the self idea, and the self is not a thing in itself but a relational expression of a greater whole. Life is relational being and the forms of that relational interaction are the unfolding of a whole idea in all its parts. Our linear experience of time is the framework of an unfolding experience - of the whole unto itself - as if in pieces set apart. As long as the nature of creation is pushed back to a past beyond recall, the presence will seem but a momentary bridge to a future set in its image. A fleeting moment to which Big Brother's boot stamps itself, in the attempt to evade and deny fears, or if you prefer -reptilian overlords!
Its life, Jim, but not as we think we know it.
Perhaps the biggest trick of the past is as a prequel of necessity and justification for the current or established framing of experience as the only possible reality now - and also as the basis from which to extend such conditions back as if they have continuity. What if we have not come from the past - but are in a sense operating through the lens of using it? When is it ever yesterday? Is the 'journey of experience' itself a creation? - or just to reiterate - a relational transform where the whole shifts in every part as an unfolding experience of existence?
Life is an expression of its environment even as thought is an expression of desire. Persistence of attention indicates value given in terms of what is desired or attracted - without any 'conscious reflection' being involved. But in giving life to the imagined modeller, we assign a relative death or mindless mechanism to a Living Universe that God never left, even if we did - or tried to and believed we have - by projecting to exclude instead of creating by extension of embrace.
The development of the physical structure through which to then behold in its terms isn't just over millions of years, but is establishing of the channels of communication that are informed as an organising energy blueprint. Not unlike a neural pathway. Blood flows before the heart has formed around it. Informational or organised self sustaining energy underlies the forms of tangible physical existence.
Perhaps there was no need for eggs in the earliest giant reptile expressions. We assume physical objects to have independent existence rather than persisting as a relational fitting to the collective theme. Gravity is not the constant we presume (and projects to our model of the Cosmos), and the environmental conditions of our past may operate more variables that we are currently ignorant of because they are either unchangably defined in our model, or completely outside our model. The realm of Consciousness is that of a shifting and changing context - and not only of contents. I hold that every shift is a total shift, but that a narrative identity presumes continuity of itself and its object world as a primary focus.
Insofar as we have given ourself - or claimed power to define, predict and control our world, are we invested in our own version or thematic expression within the idea of 'discovering' reality in our own image, and flagging our patents and asserting rights of possession as principalities usurping the true source of authority. The knowing of being is a gift of being and not a development of a sense of self-lack. Reptiles did not meet extinction, but giantism did, and later, even megafauna of the mammalian species were replaced by more fitting forms of life to the new conditions.
It can of course be argued that much of evolution is the degrading of adaptive capacity to temporary conditions that leave the species unable to re-adjust when the conditions revert or change again. This is also arguable for the human consciousness that lauds itself a pinnacle of its own theory while outsourcing ever more of its conscious ability to outsourced technological support and management systems. If we cannot recognize our own self-illusion as an dream-incubation within and increasingly armoured shell, will we not follow the Tyranosaurus before us?