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A seahorse (family Syngnathidae, genus Hippocampus meaning “horse sea monster”) is like no other animal on earth. It is the only fish that swims upright. It is not just a fish that travels on its tightly curled tail, but its whole body is designed around how it swims. For example, its elaborate balancing mechanism uses an air bubble inside of a specially designed swim bladder to maintain upright posture.

Even when it sleeps, it cannot fall over as it floats vertically in its green watery world guided by a wide rapidly moving pectoral fin located just behind its gills.  Sensitive cells at the top of its swim bladder detect when the bubble moves to the wrong place. This movement triggers several complex responses that cause the seahorse to right itself. The common 10 cm (4 ins.) high seahorse moves until the bubble tells it that it is again upright. If the bladder is punctured, the seahorse will sink helplessly to the sea bottom, doomed to die if the wound does not heal rapidly enough.

Like the strange pygmy sea dragons, seahorses spend much of their time clinging with their monkey-like prehensile tails to the seaweeds and coral around which they live. Many seahorses are not only the same color as weeds, they even look like weeds. They have no need to hide from enemies, though—the seahorse has very few enemies. Its bony plate covering and its bitter taste deter all but the desperately starving.

Seahorses live on plankton, shrimp larvae, and other small sea life by creating a powerful vacuum that sucks up food as it floats by. Seahorses have neither teeth nor a stomach, yet can effectively digest even the hard exoskeleton of their prey (Amanda Vincent.1990. Natural History # 12 pp. 34-43 see p. 36).

To watch a male seahorse give birth to several hundred tiny seahorses is a unique drama. Mother ceases her part in the reproduction task after she carefully deposits her eggs into dad’s kangaroo-like sack. There they are fertilized by the male, and remain for the next forty-five days. As soon as the 300 to 600 new seahorses are born they must rise to the surface to swallow the air they need to fill their swim bladders (J. E. Hartman. 1968. National Wildlife Magazine p. 20). Father then looks after them until they are mature enough to forage about on their own. At this time most readily wander off to fend for themselves. Occasionally, one twists its tail around dad and hitches a ride—a beautiful sight to behold.

The design contrast of this little creature with fish is evident even in its incredible eyes. Like the land-dwelling chameleon, the seahorse’s eyes can move independently. One eye can look left while the other looks right, an extremely useful design if you cannot move very fast. Whenever a seahorse swims near the surface it can also simultaneously scan both above and below the water—the best of both worlds.

Also, like the chameleon, seahorses can camouflage themselves by changing color to match their surroundings. This allows them to sneak up on, and consume, their small prey with their tubular mouths. In a matter of seconds they can become red, blue, and even yellow, depending on the species. Its bosom can puff up like that of a pouter pigeon, and its colored armor coat will intrigue the most humble of human observers.

Although seahorses are among the world’s most fascinating vertebrates, little or nothing is known about their evolution (Vincent, 1990, p. 34). Seahorses have many distinguishing features that make them unique, not just a prehensile tail and the many differences noted above, but also camouflage gills and male brood pouch (P. R. Teske et al. 2004. Molecular Phylogenetics and Evolution. 30 #2: 261-272).

If you can imagine trying to turn any other kind of fish into a seahorse, you will see why no scientist has been able to devise a plausible evolutionary route for its origins. Scientists struggle to explain the evolution and survival advantages for an animal to swim upright. Standing up while swimming forward makes swimming far more difficult—like a horse without legs in the wrong world. Yet seahorses are one of “the most graceful inhabitants of our seas … extraordinarily elegant” (W. Arrigoni.1989. Sea Frontiers. pp. 358-365 see p. 358).

Its uniqueness is also highlighted by the fact that it offers not a single solitary clue as to its evolutionary origin. Evolutionists have dated the oldest seahorse fossils back to Eocene rocks, which they claim date back about 40 million years ago. Yet no evolutionary links are known, and no fish relatives exist that are half typical fish and half seahorse.

Even its fin design is very different from that of all other fish—unlike other fish it has only one fin, a single wide fin on its back. Considered most closely related to a pipefish, largely because they also incubate their young in a pouch, seahorses are markedly different from pipefish. As Casey et al. concludes “in the absence of a reliable fossil record, it has only been possible to speculate as to the time and place of the origin of Hippocampus” (Molecular Phylogentics and Evolution. 2004. 30 #2: pp. 261-272 see p. 261).

Genetic research on seahorse evolution has not supported any evolutionary theory that explains from where they originally evolved (Casey et al., 2004, p. 261). Some genetic studies have indicated that the first seahorse species could have originated in the Atlantic biome. This theory is supported because the only ancient seahorse fossils ever uncovered were located in Italy, and seahorses are considered most closely related to pipefish, which are believed to have originated in the Atlantic biome. A biome is a major ecological community covering a large area with common characteristics which are determined by climate.

Other studies support the theory that seahorses evolved in the Indo-West Pacific region because this is where the greatest concentration of seahorses—more than 27 species—survive today. A third theory supports the idea that tropical shore species migrated around the Cape of Good Hope and established themselves in the Atlantic region (Teske, Cherry, & Matthee, 2003).

Casey et al. (2004) did a phylogenetic analysis of 93 specimens of 22 seahorse species living in the Atlantic and Indo-Pacific Oceans using cytochrome b gene sequence data. Despite a greater number of seahorse species in the Indo-Pacific region than in the Atlantic Ocean, no genetic evidence was found to support the Indo-Pacific origins theory of genus Hippocampus. The genetic data suggest that the high diversity in the Indo-Pacific results from speciation events dating from 2 million years ago to as much as 25 million years or even earlier. The results indicate that several species designations need re-evaluating, and further studies are required to determine the patterns of seahorse geographical dispersal.

Seahorses are classified as fish, but Arrigoni calls them “a mixture of two-thirds horse, one-third kangaroo, a bit of monkey, and a pinch of chameleon” (1989, p. 258). No other vertebrate reproduces as does the seahorse. Yet Cambridge University Professor Vincent Amanda noted “from snout to tail, seahorses are surprising fishes” (Amanda, 1990, p. 36). Of the over 35 species of seahorse living in oceans all over the world, none hints at their evolutionary history.

Living seahorses range from the half-inch long New Caledonian Seahorse to the 14 inch-long eastern Pacific seahorse, but all are seahorses from head to tail (Amanda, 1990, p. 36). Seahorses are members of the Syngnathidae family, which includes pipefishes, pipehorses, seadragons, and flag-tail pipefishes, yet they are very different even from all of these assumed family members.

The keratin plating which covers the seahorse and all its other unique features are evidence, not of evolution, but of meticulous engineering. Even if it existed for no other reason than for humans to behold its beauty, that would be reason enough. Too often we become so blinded by the human quest for knowledge that we forget to enjoy the world that God has made. One thing is certain—the first known seahorse is a seahorse.

Jerry Bergman
July 2010

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