Growing awareness of the complexities of sex and gender is one of the many reasons we join in celebrating the diversity represented by the Seattle Pride festivities. But did you know that sex is not so distinctly defined among many animals? It often shifts in the most fluid of environments: the ocean.
Warning: Our first example contains major spoilers. As in, spoiling the magic of one of your favorite animated adventures. Outside the imaginary world, Nemo’s dad may never have set out on his oceanic odyssey. In fact, Nemo’s dad would have become Nemo’s mom upon her untimely death by barracuda. Clownfish live in groups dominated by a single breeding pair made up of a dominant female and slightly less dominant male. The rest of the hangers-on are subordinate males. When the dominant female dies, the dominant male assumes her role—and her sex—and a subordinate male levels up to take his place.
The blue-headed wrasse takes a different tack. Each day, a single dominant male awaits passing females and spawns with the whole group. A pretty good life, right? And the other wrasse know it, so he has to be big and aggressive to defend his position. But some smaller guys have figured out a weakness in the system. Disguised as females, so sporting a yellow rather than blue head, they “sneak” into the spawning spree and release sperm on the down-low to try and fertilize some of the eggs the females release.
The females have their own strategy to spurn the system as well. When the dominant blue-headed wrasse dies, the largest female ascends to his place in the hierarchy—assuming his position along with his sexual characteristics. Her behavior becomes more aggressive, she exhibits male courtship behavior and her head transitions to the tell-tale blue. Her ovaries become testes and begin to produce sperm. Within a week, this new dominant wrasse is fertilizing the eggs of the harem.
Above and below the surface of the ocean, throughout the natural world, sex and gender are more complicated than most people realize. We are proud to share some of the science—and proud to support the human nature of Seattle’s community.
We Can’t Save Nature Without You
Sign up to receive monthly conservation news and updates from Washington. Get a preview of Washington's Nature News email.
You May Also Like
What Threatens Our Salmon?
Salmon are iconic symbols of the Pacific Northwest’s natural vitality, yet they face a myriad of threats. Go below the surface on how we’re protecting salmon with science, partnerships and policy.
Nature Photos
In Washington, our identity is shaped by rich resources and natural beauty. These photo essays celebrate our diverse connections to nature and the moments that speak to traditions while revealing our future.
Urban Trees and Climate Change
Climate change is already impacting our cities and towns in the Puget Sound– with increased extreme rain events and flooding, hotter summers, denser air pollution and more. Urban trees are a tool for fighting and adapting to climate change.