There’s no DNA evidence for yersenia pestis, which differs from the various European outbreaks since the Middle Ages. A smallpox outbreak may have been a factor in the Crisis of the Third Century. Earlier, during the Spartan siege of Athens, typhus apparently carried away a big chunk of the Athenian population.
Hauling a 300+ (hmm, sez here 350+) obelisk would indeed require a larger displacement for the freeboard. Same goes for their grain haulers. From the descriptions that survive for their Indian trade, those ships may have been enormous, larger than the Med ships, which had to ply a lot of small ports.
Lionel Casson cites a Roman-era grain ship which due to foul weather had to ride it out in the Piraeus of Athens. It was not a place that saw such ships by that time (and Hellenistic vessels of any size would have been military rather than commercial), and everyone in town came by to gawk. Casson writes that the grain haulers were really only practical at large ports, like Alexandria (Egypt was the source of much of Rome’s grain supply), Rhodes, Athens, and Rome.
In general, Roman-era vessels pushed the envelope for size, and exceeded what has in more recent centuries been considered the practical limits for wood vessels.
The ships of the yavanas referred to in Tamil literature do not (as the ancient astronaut astronuts claim) refer to UFOs, but to the Greeks’ and Romans’ vast ships, which were a spectacle each time they arrived, and due to the reliance on the monsoon winds, they arrived in great numbers during a relatively short window of time.
There’s a Roman mosaic showing an orangutan, which is from much further east, and a Han court reference to the arrival of a Roman trader from the time of Marcus Aurelius.
It’s no surprise that one classical scholar referred to the simultaneous heyday of the Roman, Satavahanan, and Han empires as the happiest period of human history.
Bttt