background on the dispersal theory of madagascar's animals

the island is ~120 my old, the animals arrived 60 or fewer my ago.

currents now flow away from the island

africa & madagascar migrated from the south, presumably disrupting earlier
currents which must have flowed toward the island.

the above explains how an ancient migration could have occurred, and why
the island was isolated from more recent migrations (which was the problem i had with it).

https://www.eurekalert.org/pub_releases/2010-01/pu-sap011910.php