Seahorses Without Stomach: Evolutionary Design à la Carte
DOI:
https://doi.org/10.22201/ceide.16076079e.2025.26.4.10Keywords:
seahorses, sea, digestion, evolution, fishAbstract
Stomachless, yet with a finely tuned appetite—that’s how seahorses live. These fish, which look more like living sculptures than predators, have replaced that organ with a digestive system tailored to their lifestyle. Their prey—tiny crustaceans and fish larvae—are sucked in whole in a fraction of a second, thanks to a snout that works like a miniature marine vacuum. Digestion takes place in an alkaline environment, driven by enzymes released directly into the intestine, while a long, folded tube holds the food just long enough to extract every nutrient. In fact, part of the process even continues inside intestinal cells. The loss of a stomach—a phenomenon that has occurred in different groups of fish—remains a mystery: some point to dietary changes, others to energy savings, or even evolutionary chance. Whatever the cause, seahorses are proof that nature doesn’t cling to a single design; it reinvents itself, sometimes with results as elegant as they are unexpected.
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