Refer to the table below showing the observed characteristics of four species of algae. Which sequence of characteristics is consistent with the current thinking about the evolution of multicellularity?
A) 2, 1, 3, 4
B) 3, 4, 1, 2
C) 1, 3, 4, 2
D) 3, 1, 2, 4
E) 4, 3, 1, 2

Question

Refer to the table below showing the observed characteristics of four species of algae.  Which sequence of characteristics is consistent with the current thinking about the evolution of multicellularity?
A) 2, 1, 3, 4 
B) 3, 4, 1, 2 
C) 1, 3, 4, 2 
D) 3, 1, 2, 4 
E) 4, 3, 1, 2

Quizplus · Accepted Answer

Current thinking about the evolution of multicellularity suggests that there was first a transition from unicellularity to coloniality, where cells form loose aggregations but retain individuality. This is followed by a transition from coloniality to true multicellularity, where cells are specialized and dependent on one another. The characteristics in species 3 and 4 suggest they are at the colonial stage, with cells loosely aggregated but still motile and individually functional. Species 1 has some specialization of cells (indicated by its filamentous structure) but still lacks true cell differentiation, so it represents an intermediate stage. Species 2 has true cell differentiation and interdependence, indicating it is at the multicellular stage. Therefore, the correct sequence is 3, 4, 1, 2.

Refer to the Table Below Showing the Observed Characteristics of Four