The Game of Survival
|Stealthy, quiet, and well-camouflaged, the sea anemones are likened to ninjas of the sea. Photo credits: Grae Hunter.|
A typical sea anemone (aka sea ninja) has to evade its predators, battle other anemones, and find its next meal in an ocean of scarcity and competition. Toxins are a sea anemone’s most vital weapon because they play a part in capturing prey, repelling predators, digestion, and interspecies competition.
The typical strategy for capturing prey involves the sea ninja patiently waiting for its victim(s). Once the anemone wraps its tentacles around the prey, nematocysts discharge and inject a lethal toxin concoction into the prey. The prey experiences intense pain and paralysis due to the mixture of neurotoxins, pore-forming toxins, and toxin enzymes.
|Once ensnarled by the tentacles of a sea anemone such as the Haeckel's Anemone, the prey will become immobilised by the painful stings released by the anemone. After which, they will become the meals of the day.|
Even though anemones have a scrumptious scheme for capturing prey, they still have to compete with other anemones for food and prey. The sea ninja not only engages in combat with other species but anemones with species as itself as well. Some anemones use acrorhagi (specialised tentacles used solely to deter other anemones/colonies from encroaching into its space) as toxic bombs, while others use catch-tentacles as their sword.
|Acrorhagi - highly specialised tentacles with a sole purpose to 'fight' against other anemones or organisms. Photo credit: Emery Hodge.|
Check out this video of Anemones Fighting with their Acrorhagi: https://www.shapeoflife.org/video/cnidarians-anemones-fight
|The Lined bead anemone (Diadumene lineata) has got some long catch tentacles!|
|Capturing prey - The sea anemone uses their tentacles around their mouth to catch prey, which becomes triggered when it comes in contact with prey. This trigger is stimulated on a stinging cell called cnidocyte, which shoots a harpoon-like nematocyst into the prey injecting toxins. Photo credit: Erica Patterson.|
|Acontium tissues found in the gastrovascular (stomach) cavity of Exaiptasia anemone. Taken from: Lam et al. (2017).|
Ultimately, the sea ninja will do whatever it takes - strike, sting and strangle - to win the game of survival.
About the writer:
Shabdita Vatsa recently graduated from the National University of Singapore with a Bachelors in Life Sciences (Molecular and Cell Biology). She spent most of her undergraduate days obsessing over sea anemones and their toxins. Her fascination became research projects, working with scientists from the Reef Ecology Lab and Protein Chemistry Lab to study anemone toxins.
A passionate writer, Shabdita loves creative writing, popular science writing, and scientific writing. You can find more of her writings on her personal page: https://lifesciencepotluck.tumblr.com/
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