Tyrannosaurus Rex "Visual Acuity"

The sensational headline reads: "Maligned T. Rex eyesight the best in animal history?"
Dino-Bird people "explain away" everything... resulting in the explanation of nothing.

"...Stevens was able to determine that T. Rex’s binocular range was 55 degrees, which is greater than a hawk, which is known for its high visual acuity. T. Rex had front-facing eyes, set into the sides of a narrow skull, which allowed for an overlap in its visual field, leading to the conclusion that T. Rex had definite depth perception."
(Source)
"...Great horned owls, like other owls, have eyes that are fixed in their socket. They cannot move their eyes up and down or side to side like humans. To compensate for lack of eye movement they can rotate their heads 270 degrees. This rotation enables the owl to see in many different directions. In addition to having an extra vertebrate to help with the neck movement, great horned owls have large yellow eyes that allow them to gather sufficient light to see well in low light conditions. They have an incredible sense of hearing, a trait which allows them to hunt at night. Their ears are located on the sides of the head. One opening of the ears is tilted upwards while the other is tilted downwards. The right ear is set higher up on the skull. This allows the owl to pinpoint exactly where the prey is located."
(Source)
"... Canadian geese also have very good eyesight and hearing. Sight is the bird's dominant sense. Compared to a mammal's eyes, they are comparatively immobile; however, birds are able to rotate their heads greater distances. Birds are also able to focus their eyes very quickly which is essential during flying. They have a large field of sharp vision."
(Source)
"...But birds have several visual adaptations that help compensate for the limitations of monocular vision. The first is an increased panoramic view. For example, mallards possess a 360-degree lateral viewing window where they can see in a complete circle at all times. People have a much narrower range of vision, which forces us to look around in several directions to piece together all of our surroundings. Bird eyes are also often set higher on the head, which increases the vertical sight plane. An extreme example is the American woodcock, which can observe not only 360 degrees laterally but also 180 degrees vertically. The benefit for birds is an increased awareness of their surroundings and a subsequent decrease in exposure to predation.
Another way birds compensate for monocular vision is rapid head movement. By moving their head rapidly from side to side, birds can observe an object with one eye from two different angles in quick succession. This creates a three-dimensional picture and greatly improves depth perception. Although difficult to see in ducks, this behavior can easily be observed in a backpedaling goose as the bird swivels its head from side to side judging the distance, location, and timing of its landing.
Monocular vs. Binocular Vision
With eyes set on the sides of their head, most waterfowl view the world with monocular vision (each eye is used separately) rather than binocular vision (both eyes view the same object at once). With the notable exception of owls, binocular vision is rare in birds. Among waterfowl, only the blue duck of New Zealand can look straight ahead. Bitterns can also do the same, but only by pointing their bill skyward."
(Source)

Not only were all T. Rex "bright red" to scare off all potential prey leading to extinction by starvation... but the bright red also tells me they were all male so perhaps gaydom (lack of reproduction) gives further insight into the extinction of dinosaurs.

"...Stevens was able to determine that T. Rex’s binocular range was 55 degrees, which is greater than a hawk,"

How Owls Twist Their Heads Almost 360 Degrees

"..The team discovered owls have backup arteries, which offer a fresh supply of nutrients when blood vessels get closed off by rapid turning.
Their arteries also swell to collect any excess blood created in the process."
Eerie Ability Not Unique
"It’s a powerful adaptive trait, Forsman said, but it’s not unique. Plenty of birds have a similar ability to look behind them. Red-tailed hawks, for example, are almost as flexible as their nocturnal cousins."
(Source)

The dino-bird people try to say that T. Rex had better vision than owls and hawks... in which reality?

T. Rex was no owl or hawk.

"...The results are promising, says David Hone of Queen Mary University of London. "We need to be careful not to overly rely on these as analogies, but in at least some ways, some animals like tyrannosaurs that are relatively distant from birds are still very bird-like."
Tyrannosaurs, the family of big predatory dinosaurs that includes T. rex, had necks that were similar to those of modern birds. So by studying how birds feed, Eric Snively of the University of Wisconsin–La Crosse and his colleagues were able to reconstruct how T. rex went about making a kill.
[...]
"Tyrannosaur necks are also similar to crocodile necks. "We can think of them as striking like a bird, and shake-feeding like a crocodile," says Snively."
(Source)
"Many people think of Allosaurus as a smaller and earlier version of T. rex, but our engineering analyses show that they were very different predators."
A key finding was an unusually placed neck muscle called longissimus capitis superficialis. In most predatory dinosaurs, such as T. rex, which Snively studied previously, this muscle passed from the side of the neck to a bony wing on the outer back corners of the skull.
"This neck muscle acts like a rider pulling on the reins of a horse's bridle," explained Snively. "If the muscle on one side contracts, it would turn the head in that direction, but if the muscles on both sides pull, it pulls the head straight back."
Tyrannosaurs like T. rex, on the other hand, were engineered to use a grab-and-shake technique to tear off hunks of flesh, more like a crocodile."
[.........] --->But the team's engineering analyses revealed a cost to T. rex's feeding style: high rotational inertia. That large bony and toothy skull perched at the end of the neck made it hard for T. rex to speed up or slow down its head or to change its course as it swung its head around. <-----
(Source)

Let's see a T. Rex pull this stunt:

Owls do not depend on their visual acuity alone.

So, Jurassic Park and the dino-bird religionists went way off course, when "explaining away" reality, and trying to make T. Rex out to be superman with "the best vision in history".

The owl depends heavily upon hearing to hunt its prey. (See above video).
T. Rex?

"...Its ears were similar to modern crocodiles, which have excellent hearing."
(Source)
"...The ears are adapted for hearing both in air and underwater.[20] Crocodilians have a wide hearing range, with sensitivity comparable to most birds and many mammals."
(Source)

In other words, T. Rex was merely average. T. Rex was just as susceptible to extinction as 99.9% of the other species that have came and went on the planet over the past 3.5 billion years.
T. Rex' ears were comparable to crocodiles, and so was their neck.
Crocodiles and T. Rex shared common ancestry.

Here's another bit, apparently the study concluding "T. Rex had the best visual acuity in animal history" -- even better than modern hawks? Implying T. Rexes were better hunters than hawks?

CONCLUSION:

"...These findings suggest that relative eye size and brain size have coevolved in birds in response to nocturnal activity and, at least partly, to capture of mobile prey."

So, what bird may lack in "eyeball size" is made up for in "THINKING-BRAIN" SIZE which was a product of evolution.

That study concluding T. Rex could "see" better than modern birds, really left out some IMPORTANT variables. How is it known (since T. Rex neck was similar to crocodile, and T. Rex hearing was similar to crocodile, it did not also have crocodile's visual acuity as well?) Do they have a fossilized eyeball? Nope. But comparative anatomy leads them to the realization T. Rex have many similarities to crocodiles.)
Then the eyeballs too.

VISION OF CROCODILES

"...It's likely that crocodiles are using some of these areas to listen, taste and watch for signs of activity (from prey, and from other crocs) before moving out to investigate."
[--- OHHHH, so modern crocodiles use OTHER SENSES for their ability to "see" the world around them. Sight is really not "the" all determining factor.]
"We tested the croc's vision by using a light-coloured object (a polystyrene ball) and it reacted as soon as it got to within a metre of its head," he says.
"We have shown quite plainly that crocodiles have reasonable vision underwater, enough to detect relatively small objects underwater within striking range of their head, and enough to detect larger objects underwater outside of striking range.
(Source)

What Causes a Crocodile's Jaw to Snap Shut?
"...Super Sensitive Skin and Teeth : The skin around the crocodile’s jaw is covered in microscopic bumps. These bumps are filled with highly sensitive nerve endings enabling the croc to detect movement, touch and vibrations. Once the nerve endings are stimulated, the crocodiles bite reflex is activated, causing the jaws to snap shut. The teeth also contain highly sensitive nerve endings. When something enters the croc’s mouth, the nerve endings in the teeth are stimulated, causing a snap reflex. Since the mouth needs to be open for anything to enter, the reaction speed here is quicker, as the croc doesn’t first need to open his jaws before snapping them shut."
(Source)

THAT... DOES NOT SOUND THE HIGHLY EVOLVED BRAIN OF EITHER A BIRD OR MAMMAL... AND THERE'S A REASON....

The rate of energy that a warm-blooded predator would need to burn to survive... compared to the brain-power of the T. Rex to be an "effective predator"... ?? Obviously the T. Rex was condemned to a diet similar to a crocodile (inability to become warm-blooded due to the near-absence of a "thinking brain")... a complete and thorough lack of ability to formulate a "planned attack".

T. REX DIET

"...larger crocodiles can go for over a year without eating a meal. In extreme situations, crocodiles appear to be able to shut down and live off their own tissue for a long period of time....the average croc eats about 50 full meals a year. When they feast, crocodiles are certainly not picky eaters. It’s said that a croc will feed on anything it can outswim or ambush and overpower. These reptiles have extraordinarily adaptable diets. Larger crocodiles will eat larger mammals and birds, but they’ll also eat fish and mollusks like snails. During difficult times, they will even scavenge for carrion. In fact, crocs will consume almost everything they encounter."
(Source)

BINOCULAR VISION... LIKE CROCODILES

"...crocodiles start the leap while stationary at the water's surface - they need to be able to see their target before they start to leap, and if the target is above them they'll tip their head upwards to get a better view.
binocular vision.
Crocodiles can judge the distance to their target very accurately - they have binocular vision in front of their heads (i.e. the visual fields of left and right eyes overlap - see right), so they can use parallax to estimate distance. Once ready, the crocodile immediately starts to use powerful sinusoidal undulations of its tail to literally push itself upwards out of the water."
(Source)
"T. rex's brain... the cerebrum (the part of the brain that we use to think) was tiny. T. rex's brain was long and almost cylindrical in shape. Only very advanced theropods, like the dromaeosaurid dinosaurs (for example, Deinonychus and Velociraptor), were probably smarter than T. rex."
(Source)

ON TO MODERN BIRDS LIKE HAWKS

Extract from "Evolution and Prehistory: The Human Challenge"

"..Unlike reptiles, who process visual information with neurons in the retina, mammals process visual information IN THE BRAIN, permitting integration with information with other senses such as taste, touch, taste and smell."
(Source)
"...Evidence from several sources indicates the avian visual system was driven by alterations of the basic reptilian plan, primarily in support of flight behaviors. Birds are highly visually dependent organisms, possessing visual capabilities comparable (and in some cases, superior) to those of another visually-dependent vertebrate, the primates. There are many basic similarities in the visual pathways of birds and mammals. These commonalities in visual systems are rooted both in distant ancestral phylogenetic relationships..."
(Source)
".........species with large eyes have evolved large brains to cope with the increased amount of visual input......."

BUT THAT.. WAS NOT THE CASE WITH T. REX AND HIS TINY CROCODILIAN-BRAIN.

BIO 554/754
Ornithology
Nervous System: Brain and Special Senses II
"...The avian eye is large relative to the size of the head & brain. For example, human eyes make up about 1% of the total mass of the head; European Starlings eyes make up about 15% of the mass of their head. The advantage: large eyes provide larger & sharper images. Birds also have 3 eyelids; one upper and one lower eyelid plus a nictitating membrane. This nictitating membrane is between the other two eyelids and the cornea and has its own lubricating duct equivalent to our tear duct.
Eye size, brain size, prey capture and nocturnality -- Behavioral adaptation to ecological conditions can lead to brain size evolution. Structures involved in behavioural visual information processing are expected to coevolve with enlargement of the brain. Because birds are mainly vision-oriented animals, Garamszegi et al. (2002) tested the predictions that adaptation to different foraging constraints can result in eye size evolution, and that species with large eyes have evolved large brains to cope with the increased amount of visual input. Using a comparative approach, Garamszegi et al. (2002) investigated the relationship between eye size and brain size, and the effect of prey capture technique and nocturnality on these traits. After controlling for allometric effects, they found a significant, positive correlation between relative brain size and relative eye size. Variation in relative eye and brain size were significantly and positively related to prey capture technique and nocturnality. These findings suggest that relative eye size and brain size have coevolved in birds in response to nocturnal activity and, at least partly, to capture of mobile prey."
(Source)
"T. rex's brain... the cerebrum (the part of the brain that we use to think) was tiny. T. rex's brain was long and almost cylindrical in shape. Only very advanced theropods, like the dromaeosaurid dinosaurs (for example, Deinonychus and Velociraptor), were probably smarter than T. rex."
(Source)

And, just how "smart" was a "smart dinosaur"?

"...Velociraptors were Dromaeosaurids, among the dinosaurs with the very highest level, so they were truly smart among dinosaurs. On this ranking, they were probably a bit smarter than rabbits and not quite as smart as cats and dogs."
However, this comparison is made more complicated by the fact that the velociraptor's brains appear to be relatively primitive, despite their large size, and they may have instead had highly developed senses with not much thinking power. That is, their brains suggest they "bit first and asked questions later" and had little capability to evolve hunting strategies."
(Source)

So in other words, without a highly-evolved brain like in mammals and modern birds, an eyeball the size of a basketball won't help you become one bit a better predator... T. Rex lacked the brain to process the visual information.

"...Using a comparative approach, Garamszegi et al. (2002) investigated the relationship between eye size and brain size, and the effect of prey capture technique and nocturnality on these traits. After controlling for allometric effects, they found a significant, positive correlation between relative brain size and relative eye size. Variation in relative eye and brain size were significantly and positively related to prey capture technique and nocturnality. These findings suggest that relative eye size and brain size have coevolved in birds in response to nocturnal activity and, at least partly, to capture of mobile prey."
(Source)
".........species with large eyes have EVOLVED LARGE BRAINS to cope with the increased amount of visual input......."
(Source)

T. Rex's ability to process visual information was extremely limited compared to the modern hawk.

"...A Red-tailed Hawk... [has] excellent eyesight which is much sharper than a human's. A Red-tailed Hawk can spot a mouse from a height of 100 feet."
(Source)

In the same scenerio, T. Rex would not know if the moving object was edible or not -- it just bit at what moved. Hawks knows what "a mouse" is and formulates a plan of attack on its prey. The hawk... sees a mouse...and knows it eats mouse. "Mice are delicious" thinks the hawk as it swoops in for the kill.
A feat which a T. Rex with "bright red feathers" could've never performed.
The T. Rex would've seen "something move" and bit... like a mechanical reaction.
The hawk's eyeballs may be smaller than T. Rex, but its brain is evolved to effectively compensate.

Why wouldn't a T. Rex bite a duck-billed dinosaur?

"Some paleontologists (notably Jack Horner) have recently begun to question whether T. rex could have been an effective hunter, given its small eyes, puny arms, and relatively slow gait (Note: many other paleontologists think that T. rex had good eyesight and was a relatively fast dinosaur.) Horner's alternative theory is that T. rex scavenged its food from other animals' kills. ...There are arguments against this scavenger hypothesis. Dr. Kenneth Carpenter (then at the Denver Museum of Natural History) found a healed T. rex tooth mark on the tail of a hadrosaur (a duck-billed dinosaur). This is evidence that T. rex was an active predator, and not simply a scavenger. Why else would T. rex bite a duck-billed dinosaur?"
(Source)
"...Crocodiles are just a killing, eating machine..."
(Source)

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