[Wonder Warthog]

"....the entire area from India to Sri Lanka and further south and southeast were contagious land due to the highly lowered sea level."

Let me guess---English is not this guy's first language. "..contagious land....", "...highly lowered sea level."

[Jedi Master Pikachu]

Or his working language. A lot of Indians’ first language isn’t English, but they can use it (especially in writing) fluently. As you’ve pointed out, this guy made a lot of typos (though contagious is almost a homonym of contiguous). As for “highly lowered sea level,” that could just be Indian English. American English phraseology is a bit off from British phraseology, too.