Simplify the following text for a Grade 11 native English-speaking person.
Original: Judging from its size , Megalania would have fed mostly upon medium to large sized animals , including any of the giant marsupials like Diprotodon along with other reptiles , small mammals , and birds and their eggs and chicks .
Simplified: Judging from its size , Megalania would have fed mostly upon medium to large sized animals , including any of the giant marsupials like Diprotodon .