Because Alfred Wegener found the examples of the same fossils were found on different continent. This explains his theory of continental drift, where millennials ago there was a huge continent called Pangaea. And the continents start to split apart. The way they move around is by rounding piggyback on the Tectonic plates.
Continents were once one landmass and have drifted apart.
Explanation:
Wegener's continental drift theory is based on the idea that the seven continents were once fused together as one super continent before eventually drifting apart under tectonic movement. This idea has received support from how continents on the map has been seen to be close fits and the finding of fossil materials across oceans from where they are currently found.