Transcript this was finished today, and im on the 40hour

Diversity in Dentition
The diversity in the teeth, jaw and
facial muscles of humans, cows and
cogs.
HUMAN Teeth!
Humans are omnivores, and so our teeth
need to be about to break down both
plants and meat.
To do this, we have both long, sharp teeth
and short flat ones...
As you can see on the diagrams, the
incisors are at the front, and are thin, flat
and wide in shape. This makes them
useful for biting and cutting not so hard
foods and chopping them up.
The canines are blunt yet pointy, their role
is to tear, cut and rip materials.
The molars and premolars are smaller
than those in a herbivores basically. They
are there to grind, chew and crush the
food we eat.
HUMAN Facial muscles!
Humans can move their jaws
side to side, forwards and
backwards and up and down.
This is thanks to very well
adapted facial muscles.
In omnivores, the masseter
muscle is the smaller of the two
main jaw muscles in humans
and assists in chewing.
The temporalis muscle is the
bigger of the two, as shown, but
is responsible for less, mainly
up and down movements.
DOG Teeth!
Dogs are carnivores so they need to
be able to kill their prey and rip and
cut raw flesh.
A dog’s teeth are adapted for
hunting and killing.
They have very long, sharp (knife
like) canine teeth which are used for
ripping, penetrating and killing prey.
They have small, sharp, pointed
incisors that are used for holding the
food and nibbling or shredding. The
molars are triangle in shape and
jagged like a blade is, similar to
scissors with the way they close
together.
DOG Facial muscles!
In carnivores, the opening of the mouth is
very large, which is because they have to
catch and hold large prey in their mouths.
The temporalis muscle is well developed,
because it must drive the canine teeth
forcefully into its prey, and is the biggest
and main muscle that dogs use.
The masseter and Pterygoid muscles are
smaller and non important, as they control
the side to side movements of the jaw, and
dogs don’t need to chew.
COW Teeth!
Cows are herbivores and so they need
teeth that are designed for a lot of
chewing grass and other plants..
The teeth very close together to make
a good biting. The incisors are wide,
flat and spade like. There are no
incisors on the upper jaw, and instead
there is a horny pad, or dental pad
some people call it. The cows teeth and
horny pad all work together to chew
and eat grass. There are no canines,
because cows don't have to rip flesh...
The premolars and molars are square
and flat also, to give a good surface to
crush.
COW Facial Muscles!
Herbivores have well-developed masseter
and pterygoid muscles because they need
to move their jaws in a circular motion to
grind and crush plant material. The
masseter muscle is HUGE. Their
temporalis muscle is not as important, and
way smaller, because herbivores do not
need to open their mouths wide to catch
prey and they don't need to rip or tear
flesh.
IN CONCLUSION....
Dogs, Humans and Cows all have different teeth and facial muscle
structures because of the different diets they eat. Each mammals
mouth is specially adapted for the food they eat. Herbivores,
carnivores and omnivores all have very different diets, and so
must have teeth right for them..
Mammals have 4 different main kinds of teeth.
Incisors – For snipping and nibbling or cutting food.
Canines – For ripping, tearing and killing prey.
And Molars and Premolars – For chewing and grinding down food.
Mammals have 3 main jaw muscles which control chewing
motions.
Masseter - provides slow, powerful jaw closure with
forward/back/side-to-side chewing motions.
Temporalis - delivers fast and forceful jaw closure in the up/down
plane.
Pterygoid - produces sideways jaw movements.