#amphiprion

Red Sea Clown Fish aka Two-banded Anemonefish (Amphiprion bicintus), family Pomacentridae, order Blenniiformes, Red Sea, Egypt

A Clark's anemonefish (Amphiprion clarkii) infested by a tongue-eating louse (Cymothoa exigua) in Indonesia

NEMO FISHES CAN COUNT STRIPES, SCIENTISTS SAY

Clownfish, aka anemonefish, famous by their distinct white bar patterns seen in Disney’s Finding Nemo, can count up to three, a new study finds.

There around 28 different species of anemonefish know to date, having between 0 to 3 white stripes, which has been suggested to be important for species recognition. In a recent study, researchers found out that in lab conditions, common anemonefish (Amphiprion ocellaris), a species that displays three white bars, when faced with an intruder fish, attacked their own species more frequently than other species of intruding anemonefish.

Recearchers tested how common anemonefish could count number of stripes, and they used orange plastic models with different numbers of bars, and compared whether the frequency of aggressive behavior towards the model differed according to the number of bars. The frequency of aggressive behavior toward the 3-bar model was the same as against living common anemonefishes and was higher than towards any of the other models.

-Plastic models used to measure the aggressive behavior of clown fish. Clownfish could count stripe and shown aggresive behavior following the number of stripe. Photo by Kina Hayashi.

Researchers believe common clowfish count the number of white stripes as a cue to identify and attack only competitors that might use the same anemone where they live, using counting as an important behavior for efficient host defense.

Photo: Gaell Mainguy ·

Pink anemonefish (Amphiprion perideraion) in closed anemone -

Black and white Clown Fish are a striking colour variant of the common Clown Fish (Amphiprion ocellatus). This species is known for its protoandrous hermaphroditism, which is a type of sequential sex change. Groups that live together consist of two large fish, the breeding male and female, and several other smaller fish. If the female is predated or removed, the breeding male will transform into a female, and one of the smaller fish will rapidly grow to be the sexually mature male of the group. 

Percula Anemonefish aka Orange Clownfish (Amphiprion percula), family Pomacentridae, order Blenniiformes, Solomon Islands

Orange-fin Anemonefish (Amphiprion chrysopterus), family Pomacentridae, order Blenniiformes, Fiji