Cranial Kinesis and Feeding in Snakes

Audio Transcript Auto-generated

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  Hi

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  I'm Michaela fox and this is my presentation

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  on cranial kinesis and feeding in snakes.

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  In theory, snakes seem like simple creatures since they have no arms or legs,

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  however, they're anything.

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  But

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  if you've ever seen a snake feet on its prey,

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  then you would know that they are able to open their mouth to an exceptional angle.

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  The mechanism that allows for this special

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  function is known as cranial kinesis and it

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  gives the snakes the ability to consume prey that is larger than their head.

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  Most people say that snakes unhinge their jaws,

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  but this is not the case.

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  It is simply cranial kinesis at work.

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  According to the textbook,

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  cranial kinesis refers to the movement between the upper

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  jaw and brain case about joints between them.

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  Kinetic skulls

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  like those found in snakes

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  allow for a higher range of motion between the jaws.

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  You can compare this to an a kinetic skull which does not

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  have any type of movement between the upper jaw and brain case.

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  There's also

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  miso kinesis,

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  meta kinesis and pro kinesis, which are named based on where a hinge joint

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  called the cran trans cranial joint passes through.

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  In medical crisis, the hinge passes across the back of the skull

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  permitting rotation between the neuro cranium and the outer, dramatic cranium.

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  If a joint passes through the dramatic cranium behind the eye,

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  the skull exhibits miso penises.

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  If a joint in the dramatic cranium passes in front of the orbits,

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  the skull exhibits pro kinesis

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  Today, kinetic skulls characterized most vertebrates.

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  However, this does not include

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  modern amphibians,

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  turtles,

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  crocodiles and mammals,

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  with the possible exception of rabbits,

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  these animals tend to have an a kinetic skull because of the

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  force needed to obtain and true their prey prior to digestion.

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  Cranial kinesis provides a way to change the

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  size and configuration of the mouth rapidly.

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  It also allows teeth bearing bones to move

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  quickly into strategic positions during rapid feeding.

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  On the other hand, and a kinetic skull allows animals to suckle easier,

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  which is a trait mainly found in mammals.

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  Loss of kinesis in the skull also helps mammals to firmly

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  because they have sets of specialized teeth that

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  are secure and routed to the jawbone.

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  The main benefit of cranial kinesis and snakes is the

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  ability to consume prey that is larger than their head

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  without having to break it down into smaller pieces.

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  A disadvantage of a of a kinetic skull is a reduced bite force.

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  Yeah,

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  the evolution of cranial design and

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  lepidus Koreans,

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  which includes lizards and snakes,

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  is characterized by a general trend towards the loss of cranial elements.

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  Since lizards and snakes are both reptiles,

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  one can see the many similarities amongst their

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  skulls prior to the dispersion of each series

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  species

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  when looking at both of the skull, as you can see many similarities and differences,

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  for instance, snakes and lizards have many of the same bones that compose the skull,

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  but the bones are placed in varying locations along the skull.

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  The biggest difference between lizard and snake skull is that there

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  is much space between the bones and the snake skull.

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  While the lizard has many bones that are closer together,

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  the lizard has many different bones that are off used together

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  while the snake has fewer bones that are spaced further apart,

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  which allows for the animal to open its mouth very wide.

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  In snakes,

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  the frontal and parietal bones have grown down around the size of the skull

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  to for most of the walls of the brain case,

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  upper and lower temporal bars are lost and the lower jaw is unf used in the midline.

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  As you can see in this picture I have here,

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  this is a comparison of lizards and snakes, skulls

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  and you can see that the lizard skull has a more fused

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  skull while the snake has a lot of space

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  between

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  the bones, which

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  is the main concept behind the cranial kinesis.

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  Yeah,

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  most snakes have no direct connection between the upper jaws and brain case.

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  The palatine and maxillary are connected by long ligaments

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  which helped give the animal greater freedom of motion.

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  Snakes have a pro kinetic school,

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  as stated earlier.

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  This means that there is skull movement via a trans verse joint

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  that passes through the dramatic cranium anterior to the ocular orbit,

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  having a joint in the back of the mouth is what allows for the large range of motion.

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  The scene when a snake opens its mouth to consume prey.

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  The snake skull is comprised of four functional units which includes

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  the brain case,

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  the snout,

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  the palladio maxillary apparatus, which is also known as the upper jaws,

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  and the mandibular apparatus,

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  which is also known as the lower jaws because of cranial kinesis.

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  Each of these sections can move independently from each other,

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  but the brain case stays primarily stationary

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  in snakes, the lower bones of the jaw, also known as the mandibles,

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  are not connected as they are in mammals,

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  each mandible is attached by a stretchy ligaments

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  which allows the mandibles to spread apart laterally.

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  This increases the width of the mouth,

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  allowing a larger prey to be consumed.

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  The mandibles are loosely connected at the back of the skull,

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  allowing for greater rotation than most animals have.

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  The mandibles move independently of each other,

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  slowly inching the prey into the throat.

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  Although the process of eating may take a while,

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  especially since snakes do not chew their prey,

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  they just

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  chemically digested.

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  This can often lead to them coughing up partially digested meals.

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  The great freedom of rotation between elements of the

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  can a

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  cinematic chains,

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  the independent movement of each and the ability to

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  flare the flexible jaws outward to accommodate bulky prey.

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  I'll account for the suppleness of snake jaws,

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  the movements of the palatine interrogate oid do the actual swelling of the prey,

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  the lower jaws mainly press the prey against the upper jaws.

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  The teeth on the dysentery and max ella do little in the process of feeding,

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  since they rarely come into contact with the prey

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  and do not play an active role in swallowing

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  without the kinetic series of linkages found in these animals,

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  jaw closure would be scissor like and draw closing

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  forces on the prey would be a forward component

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  that might deflect or squirt the prey out of the mouth

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  together with the flexible palladio maxillary

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  apparatus.

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  The three part

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  lower jaw allows snakes to open their mouths very wide,

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  Walk their heads over

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  and consume prey that is as big as they are

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  without having to break it into smaller pieces.

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  Snakes also have a series of linked bones on the left and right side

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  that are not joined directly.

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  The experience independent displacement,

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  which is a feature that allows alternating left and right

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  reciprocating motion of the jawbones over the prey that is being swallowed.

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  This independent motion and outward spreading of the jaws

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  allow snakes a swallow large prey.

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  This is the mechanism at work when people say that snakes unhinge their jaws.

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  Yeah,

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  snake fangs are modified teeth with hollow core so

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  that venom flows from their base into the prey.

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  There are four different arrangements of things

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  and teeth a snake could possibly have.

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  There's

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  a glyphs which are snakes that have normal teeth.

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  All of these teeth are similar in size and shape.

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  These snakes are typically non venomous and are harmless to humans,

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  much like the burmese python.

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  There is

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  a pistol glyphs which have grooved rear things.

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  These snakes have enlarged teeth in the back

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  of their jaw that are grooved to channel venom

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  because these things are in the back of their mouth

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  and makes it much harder for the snake to inject the victim.

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  Well

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  it's venom.

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  This means that these kinds of snakes are typically harmless to humans.

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  However, certain species make him a toxins which can destroy red blood cells.

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  These snakes must quickly move, pray to the back of their mouth to inject the venom

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  mixers.

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  Pro terra glyphs, which have grooved front things.

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  This category includes cobra's and sea snakes which

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  make neurotoxins that can negatively affect the brain.

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  These snakes have very few teeth except for their large things.

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  The snake must hang onto the prey in order to inject the venom

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  and lastly

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  there's Selena glyphs which have hollow front things.

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  These things are folded up against the roof of the mouth.

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  They can inject large quantities of venom.

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  These types of things are unique to viper, such as the rattlesnake

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  the snakes with normal teeth and no things are referred to as basil snakes.

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  While the other three types of things are found in advanced snakes.

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  To sum everything up.

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  Cranial kinesis is the mechanism that gives snakes the ability to eat,

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  pray that is bigger than their head.

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  Snake skulls have evolved to have much space between the bones,

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  which allows them to open their jaws to a higher extent.

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  The palatine and Mexico are connected by longer ligaments.

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  A snake's pro Connecticut school allows for a great range

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  of motion between the brain case and lower jaw.

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  Contrary to popular belief, snakes don't unhinge their jaws to eat.

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  They simply are able to open their mouths really wide

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  because these longer ligaments in the back of their mouths,

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  snakes have mandibles are attached by strangulation,

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  stretchy ligaments.

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  These mandibles move independently of each other,

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  allowing the jaws to expand to fit larger prey into the mouth of the snake.

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  Yeah,

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  thank you.

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  Yeah.