“Duckbills were supposedly croc-style swimmers, moving by strong, easy, side-to-side flexures of their tail. Therefore, the optimal design would feature vertical tail spines. But duckbill spines all slanted strongly backward, exactly as in land-living lizards, not in swimmers.
Another problem in the duckbill's swimming equipment lies in the profile of the tail. The deepest part of the croc's tail is close to the end, because the end swings through a wider arc than does the base in moving side to side. Thus the tail is deepest where it can do the most good in pushing against the water. All powerful tail-scullers have such deep tail ends. But duckbill tails were deepest at the hips and become progressively narrower from top-to-bottom toward the tip - another caudal feature nearly totally maladapted for its primary function.”

— Robert T. Bakker , book The Dinosaur Heresies

The Dinosaur Heresies: A Revolutionary View of Dinosaurs (1986), Longman Scientific & Technical, p. 153
The Dinosaur Heresies (1986)

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Robert T. Bakker 30

American paleontologist 1945

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“The sum of evolutionary evidence is thoroughly damning. In nearly every modification of the evolutionary process made in the duckbills as they developed from their dryosaur ancestors, the duckbills suffered a diminution of their swimming potential. Their fore- and hind paws became shorter and more compact, not longer and more widely spread. Their tails got weaker and stiffer. Far from being the best, the duckbills must have been the clumsiest and slowest swimmers in all the Dinosauria. If pressed, they probably could paddle slowly from one riverbanck to another. The central theme of their bodily evolution was indeed specialized - orthodox theory was right on that point - but the direction of specialization was landward. These dinosaurs were specialized for a totally terrestrial existence.”

Robert T. Bakker book The Dinosaur Heresies

The Dinosaur Heresies: A Revolutionary View of Dinosaurs (1986), Longman Scientific & Technical, p. 154-155
The Dinosaur Heresies (1986)

“There may be some ground for believing that brontosaurs ate… soft foods. If the possibility of gizzard stones is ignored, the brontosaurs' dentition does seem little equipped to deal with meals of tougher plants. But there are no ground whatsoever for believing it of duckbills. The mouth of a duckbill dinosaur contained one of the efficient cranial Cusinarts in land-vertebrate history. Duckbill teeth and jaws were incomparable grinders, designed to cope with foods right inside the duckbill's oral compartment.”

Robert T. Bakker book The Dinosaur Heresies

The Dinosaur Heresies: A Revolutionary View of Dinosaurs (1986), Longman Scientific & Technical, p. 160-161
The Dinosaur Heresies (1986)

“A bird makes the same use of wings and tail in the air as a swimmer does of his arms and legs in the water.”

Leonardo Da Vinci (1452–1519) Italian Renaissance polymath

The Notebooks of Leonardo Da Vinci (1938), XVII Flight

“Every betrayal contains a perfect moment, a coin stamped heads or tails with salvation on the other side.”

Barbara Kingsolver The Poisonwood Bible

Source: The Poisonwood Bible

“Swinges the scaly horror of his folded tail.”

John Milton On the Morning of Christ's Nativity

Hymn, stanza 18, line 172
On the Morning of Christ's Nativity (1629)

“To fear is one thing. To let fear grab you by the tail and swing you around is another.”

Katherine Paterson book Jacob Have I Loved

Source: Jacob Have I Loved

“No living reptile has cheeks. But no living reptile has grinding teeth anything remotely resembling those of a duckbill. If the duckbills could have evolved such unreptilian teeth, why couldn't they have evolved unreptilian teeth?”

Robert T. Bakker book The Dinosaur Heresies

The Dinosaur Heresies: A Revolutionary View of Dinosaurs (1986), Longman Scientific & Technical, p. 165
The Dinosaur Heresies (1986)

“The problem comes up because we ask the question in the wrong way. We supposed that solids were one thing and space quite another, or just nothing whatever. Then it appeared that space was no mere nothing, because solids couldn't do without it. But the mistake in the beginning was to think of solids and space as two different things, instead of as two aspects of the same thing. The point is that they are different but inseparable, like the front end and the rear end of a cat. Cut them apart, and the cat dies. Take away the crest of the wave, and there is no trough.
Here is someone who has never seen a cat. He is looking through a narrow slit in a fence, and, on the other side, a cat walks by. He sees first the head, then the less distinctly shaped furry trunk, and then the tail. Extraordinary! The cat turns round and walks back, and again he sees the head, and a little later the tail. This sequence begins to look like something regular and reliable. Yet again, the cat turns round, and he witnesses the same regular sequence: first the head, and later the tail. Thereupon he reasons that the event head is the invariable and necessary cause of the event tail, which is the head's effect. This absurd and confusing gobbledygook comes from his failure to see that head and tail go together: they are all one cat.
The cat wasn't born as a head which, sometime later, caused a tail; it was born all of a piece, a head-tailed cat. Our observer's trouble was that he was watching it through a narrow slit, and couldn't see the whole cat at once.”

Alan Watts (1915–1973) British philosopher, writer and speaker

Source: The Book on the Taboo Against Knowing Who You Are (1966), p. 26-27

“She would sweep the floor – unending expanses, acres and acres of floor – with a short broom called the jhadu, swiping away the dust in an arc with its long tail, which reminded one of the drooping tail of some nameless, exotic bird.”

Amit Chaudhuri (1962) contemporary Indian-English novelist

A Strange and Sublime Address (1991)

“If a coin comes down heads, that means that the possibility of its coming down tails has collapsed. Until that moment the two possibilities were equal.
But on another world, it does come down tails. And when that happens, the two worlds split apart.”

Philip Pullman book Northern Lights

Source: The Golden Compass

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Robert T. Bakker 30

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