Question

what is a key DIFFERENCE between the colonial and aggregation hypotheses for multicellularity

Answer 1

The key difference between colonial hypothesis and aggregation hypothesis is that,

The colonial hypothesis suggests that earlier animals are originated from the symbiosis of many organisms of the same unicellular species. But aggregation hypothesis says that multicellularity is evolved when a group of function-specific cells aggregated into a mass which in turn moved to a multicellular unit.

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