Q 01/05

What does the breeding male in a clownfish group do when the group's top-ranking fish disappears?

A) Leaves the group

B) Changes sex

C) Stops eating

D) Goes into hiding

Answer · why

B) Changes sex

He changes sex: the male becomes the group's new breeding female, and the next fish in line takes over as her mate. The switch can take months to comp...

Q 02/05

What covering a clownfish's body is thought to stop a sea anemone from stinging it?

A) A film of oil

B) Extra-thick scales

C) A layer of mucus

D) A coat of sand

Answer · why

C) A layer of mucus

A layer of mucus does the trick, seeming to copy the anemone's own slime so its stinging cells never fire. A newcomer still spends minutes or even day...

Q 03/05

Which fish does most of the clownfish egg care, guarding and fanning the clutch until it hatches?

A) The father

B) The mother

C) An older sibling

D) A neighbouring fish

Answer · why

A) The father

The father does the babysitting, cleaning the clutch and fanning it with his fins for the six or seven days it takes to hatch.

Q 04/05

Given small and large bits of food in experiments, what does a clownfish do with the large ones?

A) Buries them in the sand

B) Feeds them to its anemone

C) Saves them for its young ones

D) Drops them on a rival

Answer · why

B) Feeds them to its anemone

It feeds them to its anemone and keeps the small pieces for itself. The host gets more than meals from its lodger, which also picks off its parasites.

Q 05/05

How do orange clownfish cope when a marine heatwave makes the water around them too warm?

A) Grow extra fins

B) Swim to deeper water

C) Shrink their bodies

D) Change their stripes

Answer · why

C) Shrink their bodies

They shrink their bodies to handle the heat stress. Fish that shrink along with their breeding partner have a better chance of surviving the heatwave.