Sorry for the late reply.Drop bear: if it did exist it could be a relative of the Koala that evolved a carnivorous feeding habit. Several extinct tree kangaroos like Balbaroo evolved a carnivorous feeding style. Furthermore the famous "marsupial lion" evolved from plant eating ancestors and was more closely related to modern herbivorous marsupials (diprotodontids) than carnivorous ones and is believed to have ambushed prey by jumping down from a tree onto its' back. What is strange about the description of the drop bear is the presence of 2 large canines. This would be possible as koalas have two upper canines (albeit tiny ones) but still peculiar as the diprotodontids that took up a carnivorous lifestyle modified their two front incisors to fill the role that canine teeth do in other carnivorous mammals so if a koala evolved a carnivorous lifestyle, you'd expect it to do the same.Chupacabras: This is a tough one but it appears to have opposable thumbs suggesting it is a primate but it also has features of some of the most conserved placental mammals such as claws and digigrade hindlimbs so it would be a branch off all other living primates. These early primates were believed to have been nocturnal insectivores so perhaps the Chupacabras evolved blood drinking lifestyle (kind of like how vampire bats evolved) and some of its' back fur evolved into a quill. One tough thing is that many accounts say it has a mosquito like proboscis that comes from its' mouth to such up blood. A possible explanation is that this is a modified tongue with a callous tip that it rolls, pierces into the arteries and uses muscular contraction waves to suck up the blood.
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I'll give it a try but I don't think most would be plausible.
Then what fantasy creatures are you referring to? Video game ones, lol? And alright! Pegasus! ;)
That's definitely not biologically possible. There's no way a mammal would evolve avian feathers. Also the wings are too small to lift a horse off the ground.
Oh well, I’ll still study Greek mythology anyways.
Can you make one exception for me and pretend there’s some magic involved?
That's not my fiedl :P