Sex change in clownfish
Learning stageStage 4, Stage 5, Stage 6
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The three banded anemone fish, also known as the clownfish, is capable of a sex change. The fish all start their lives as males, but as they grow older and bigger, they eventually become female.
In her video, Marissa makes a case to make the film Finding Nemo more scientifically correct by suggesting some creative changes to the script! You'll also learn from Dr. Justin Rhodes about the neurological changes that take place in clownfish brains while they undergo their sex change.
- The process in which a male turns into a female later in its life is known as protandrous sequential hermaphroditism, or protandry.
- Clownfish are part of the genus of Amphiprion which consists of 30 species of fish, all living in or near sea anemones.
- The symbiotic relationship (meaning mutually beneficial) between fish and anemone is fascinating. The anemones' stinging cells protect the fish from predators, while at the same time, the constant swimming around of the fish circulates the water, and with that supplies oxygen to the anemone.
- What do you call animals that live in groups led by females? Can you think of other animals that do the same? List them.
- Research another three pairs of Australian species (animals, plants, fungi etc.) that live in a symbiotic relationship.
- The opposite of protandry is known as protogyny and involves animals starting life as a female and later developing into a male. Identify some advantageous and disadvantages for either of these forms of sequential hermaphroditism.
About the video
Finding Nemo is a fun movie but in Sex Change in Clownfish, Marissa shows the science is a little fishy. Combining expert opinion with graphics to map their complex reproductive hierarchy, she explains that all clownfish have male and female reproductive organs. This means if a breeding female is lost, the dominant male can switch sex to replace her.
Sponsored by the University of Sydney, the Sleek Geeks Science Eureka Prize is a national short film competition that encourages school students to communicate a scientific concept in a way that is accessible and entertaining to the public while painlessly increasing their science knowledge. It is intended to support budding young scientists across the nation, who will be our future leaders in research, discovery and communication. You can learn more about the Sleek Geeks Science Eureka Prize here.