In contrast to the heights of rational thinking attained by the finest of the Greek minds, the Romans, even the highest and the lowest, the educated and the uneducated masses throughout the empire, were increasingly responsive to some irrationality. A great example of this is the collection of ‘marvels’ by Phlegon, a freed slave of the emperor Hadrian which acted as tabloid titillation for the masses.
There was born in Rome a hermaphrodite in [125BC]..On this account the senate bade the pontiffs [chief priests] consult the oracles..
Pretty ordinary so far.
There was brought before Nero a child having four heads and its other members corresponding, in the year [61 AD]. And another child was born with its head growing out of its left shoulder
Or:
There happened an incredible wonder in Rome in the year ...[49 AD]. One of the most esteemed serving women of the wife of Raecius Taurus, a man of praetorian rank, gave birth to an ape
And how about mystical creatures? Is this the first ever mention of dinosaur bones? I’ll let you decide.
Not a few cities of Sicily and the area around Regium suffered from the earthquake and not a few of the peoples in Pontus were also shaken. In the fissures of the earth were revealed bones of quite large size. They were astounded and shrank from moving them but sent a tooth to Rome as a sample. The tooth was a foot long or larger. The envoys showed it to [emperor] Tiberius and asked whether he wanted the heroic figure brought to him. Tiberius made a wise decision by which he both did not deprive himself of learning its size but also avoided the desecration of its grave. He summoned a geometer, Pulcher, famed for his skill and bade him reconstruct the face in scale to the size of the tooth. Pulcher calculated the proportions of the whole body based on the tooth and fashioned it [in clay?] and presented it to the emperor. Tiberius, satisfied with the viewing, ordered the tooth returned.
One should not mistrust these reports, reflecting that in early times nature in its prime bred everything close to the gods, but as time wasted away the size of the creatures wasted with it.
(Phlegon. Amazing Stories. Xx-xxviii. Abridged)