You know that characteristic funky seaweed smell? It isn’t a by-product of the plant’s metabolism or environment. It’s a scent manufactured by seaweed for one reason only; to lure the sperm of a mate.
When you sniff dried seaweed, or when you add regular seaweed to a dish, you notice a pungent green scent. The chemicals responsible for that scent are dictyopterenes. There are various kinds of dictyopterenes, but they all look, roughly, like long chains of atoms that end in hexagonal or triangular structures. The stinkier ones have several sulfur atoms added to the mix, both along the chain and in their ending structure.
At first people thought that dictyopterenes were the inevitable coping methods of a plant that spends its days soaking in brine, or at least the result of that plant being washed ashore and baking in the sun. But the scents aren’t coincidental. The ocean is a big place and seaweeds are stuck to only one part of that place. In order to mate, they need to go to extremes. This means releasing a lot of sperm, and it means doing everything possible to lure the sperm of other plants of their own species. The dictyopterenes that seaweed puts out act as guiding signals to voyaging sperm.
So, before you head to the beach this weekend, remember two things. If you have that seaweed wrap, you’re at least partially enjoying the taste and smell of seaweed sexual signals. And if you go into the ocean, you are lowering yourself into a body of water filled with the sperm of thousands of different species.
[Source: The Smell of Seaweed Sex]