Echinoderms use pheromones to communicate with each other.
Modern echinoderms include starfish and sea urchins.
Starfish use pheromones to communicate with each other.
How do starfish communicate?
Options:
A. huddle together
B. sound
C. interact
D. Vibrates
E. wave in air
F. during the day
G. Decibels
H. Pheromones