Bigfoot, Sasquatch, and the Abominable Snowman (the Yeti) - are all supposed to be mammalian creatures of larger than man proportions, furry, powerful, ... but there is still no physical evidence out there to support the claims of their mysterious, shadowy existence.
We do not have a single skeleton or verified piece of fur, or lost teeth, bite marks left behind, droppings, etc.
Many people claim to have seen them. And there are some interesting videos purporting to show them walking or running. It is interesting that we have never found a dead one anywhere. In North America, one would think that they would have to cross freeways once in a while, like deer do while migrating.
Some of the tracks found have proven to be fake, but we should not automatically conclude that all Bigfoot tracks "must" be fraudulent. There are counterfeiters who make fake money. But that does not mean that all money is counterfeit.
For dinosaurs (dragons) we have many skeletons, some long sets of dinosaur tracks preserved in rock, skin imprints, fossilized dinosaur eggs, unfossilized bone marrow, coprolite (fossilized dino droppings/dung) and legends of humans seeing dragons on every continent. But this is not so for the legends of Bigfoot (Sasquatch) creatures. We still have zero physical evidence of their past or present existence.
Hmmm ... let us briefly speculate. It would seem like they'd need powerful senses in order to have evaded man in the modern world for this long, should any of these creatures actually exist. They could not be dumb brutes and they're evidently not aggressive against man. They'd need either incredible vision, powerful hearing, acute smell, or some combination of these as prerequisite, right? (In other words, in this speculation, they would have to always sense humans and man-made machines before we are able to sense or see them.)
We know that certain creatures use radar, like bats and porpoises.
Electric eels and certain other aquatic life find prey using electrical
signals; eels can even stun prey with a powerful electric charge.
It is about 100 volts per foot long; so a 6 foot long eel packs a 600 volt
blow if disturbed! What if these big furry creatures can either see
in infrared or can detect by electric impulses? After all not only
undersea porpoises, but also flying bats, have unique radar capabilities.
Elephants communicate over long distances by ultra-low sound waves that
humans cannot hear. Dogs though can hear much higher frequencies
than man. Many animals seem to know when an earthquake is about to
happen. We only find out after everything starts violently shaking.
Some dogs have been able to predict a person's epileptic attack.
Some creatures are beautifully bioluminescent including fireflies and certain
deep sea fish. A chameleon can opt to change the coloration across
its entire body. Kangaroos have pouches, can hop, and can box; but
would we know any of this if they also had a great fear of man and could
run (or hop) away at great speeds? If sasquach exists they must be
able to find their dead before we do either by smell or by some other means,
following a trail left behind. Maybe they are loyal and look out
for each other, while being afraid of human contact. What if they
bury some foods like squirrels or dogs. Perhaps they bury their droppings
like cats. If electrical, then cars, houses, and all electrical devices
may sound "loud" (emitting magnetic fields?) long before they'd come into
the bigfoot's visual range. So they stay away. A bloodhound
can follow a trail from hours or even days later. What if the yeti
has a sense of smell 10x more powerful than a bloodhound? What if
the sasquach can see in infrared bands of light over distance with precise
focus? Or what if the bigfoot uses electrical impulses similar to
eels? Without some kind of inherent powerful sensory abilities, even
though theoretically possible, these creatures seem to be only fictional.
We still have no physical evidence of their existence.