The human-like incarnations also are not similar in characteristics either.
Boar Avatar - purely animalistic characteristics - violent and hunter-like characteristics which uses its body parts (turks and hands). Early humans comes with such features, using hands and teeth to gather food.
Man-lion Avatar - semi-animalistic, semi-intelligent characteristics. Still have that violent and hunter-like characteristics but this time, it tops up with intelligence. Early humans (around 3.1 million years) have such features.
Drawf Avatar - more human, more intelligence, capable of using tools. Humans - hunter, gatherers, following the herds and developing tools such as hunting tools, cutting, fire and etc.
Pasurama - same as above, but this time, has dimension of Spiritualism, capability to use complex tools and maybe even toiling the land. Probably the 1st generation to toil the land and settle in a spot as shown by the Avatar when He took out 21 Kyastria in fields of Kuruskestra.
Rama and Krishna - Very intelligence, refined spiritualism, highly socialized structures, Law, etc.