This is a very strange sentence:

"Homo is the genus of great apes that emerged around 2.4m years ago and includes modern humans."

That is not a normal way to describe the ancestry of humans. In between apes and humans were the Australopithecus:

http://en.wikipedia.org/wiki/Australopithecus

The genus homo is usually said to have started with homo habilis:

http://en.wikipedia.org/wiki/Homo_habilis

Normally one doesn't refer to one genus as being part of another genus.

Also the date "2.4m years ago" is controversial. If homo habilis is reclassified as australopithecus, then the genus homo emerges much more recently than 2.4 million years ago.