The evolution of complex multicellularity in eukaryotes
A) occurred only once, in the common ancestor of all eukaryotes.
B) occurred only once, in the common ancestor of all multicellular eukaryotes.
C) occurred only once, in the animal lineage.
D) is not documented by the fossil record.
E) occurred independently in several different eukaryotic lineages.

Question

Quizplus · Accepted Answer

There is evidence that complex multicellularity evolved independently at least six different times in eukaryotic lineages, including animals, fungi, red and brown algae, green algae, and slime molds. This is supported by comparative genomics, which shows that different signaling pathways and genetic mechanisms have been used to achieve complex multicellularity in different lineages. The evolution of complex multicellularity is also documented by the fossil record, which shows the appearance of large, anatomically complex organisms in multiple lineages over the course of millions of years.

The Evolution of Complex Multicellularity in Eukaryotes