The timeline for when humans first took to the seas keeps getting moved back. A few years ago, stone tools were found on the island of Crete which were dated to 130,000 years ago. Likewise, stone implements on the island of Flores in Indonesia have been dated back to 700,000 to 800,000. Both Crete and Flores could only have been reached by some sort of boat or raft. Likewise, human remains and stone tools found in Spain dating to over a million years ago may indicate that some ancient hominin navigated the hazardous Straits of Gibraltar from Morocco.
Recently, a researcher has offered a new theory, suggesting that Homo erectus, a hominid predecessor to modern Homo sapiens, could have been a sailor and might have been the first to develop language in order to communicate while underway on a boat.