Seahorse Family Story
Seahorse is a general name of the fishes in the family Syngnathidae. "Hippocampus" comes from the Ancient Greek hippókampos, itself from híppos meaning "horse" and kámpos meaning "sea monster" or "sea animal", which concludes to a sea monster that looks like a horse. The name is actually influenced by ancient Greek mythology, in which the seahorse was described as the horse of the god of the sea.
At present, there are as many as 42 species of seahorse recognized in the world (nearly half a dozen seahorses are still in dispute), and China is the country with the richest species of seahorse in the world, with 14 species in total, accounting for one third of the world. These seahorses come in all shapes and sizes.
All of the seahorses have some morphological similarities, such as a horse-like head, a common feature of fish, which is fins (though only dorsal and the pectoral fins are more developed), a tail for grasping objects like a New World monkey, and the most peculiar is that the male seahorse has a brood pouch (said when introducing striped hippocampus). Therefore, the sea horse can be absolutely rated as the "four unlike" in the ocean.
The seahorse's head is the most distinctive. In addition to having a straw like snout, a crown on the top of the head, and buccal spines on each side of the cheek, some species of seahorse have a unicorn-like nose spines between each nostril, and a pair of eye spines above the eyes. These characteristics vary from species to species and are often used as a quick way to identify a species.
How big is a seahorse?
Don't be fooled by the picture above, it's fake. Seahorses are only small fish in the sea, and the largest of them can only grow to about 35cm, such as H. Abdominalis and H. Kelloggi which are distributed in China and regarded as "tall, rich and handsome" in the seahorse family.
However, there are also very small and cute seahorse species, such as H. Bargibanti, which usually grow to no more than 2cm in adult size. For this, they have become the star animals of macro photography enthusiasts and divers alike.
They've been on earth for 20 million years
The origins of seahorses can be traced back to more than 30 to 20 million years ago, in waters from what is now Southeast Asia to Northern Australia. The seahorse is most closely related to a group of Syngnathidae fishes called "Idiotropiscis" . The biggest difference between the two groups is that the head and trunk of seahorses can be bent, while the Idiotropiscis cannot be bent to a high degree. Seahorses are upright, while Idiotropiscis are prone.
They have five special powers
As the saying goes, "A sparrow may be small but all its vital organs are there." In addition to their unusual appearance, seahorses also have some little-known characteristics.
- Male seahorses get pregnant and give birth. There's nothing like it in nature. The maleseahorse is equipped with a brood pouch between its belly and tail that functions like a mammalian uterus. It works better than a kangaroo's pouch because it not only provides a sanctuary for the baby, but also offers nutrition. Why this is so is a mystery. Jokingly, maybe God thought it would be unfair if all femalesin the world are responsible for producing the offspring. That's why seahorses are so unusual.
Seahorses are adept at camouflage. Some seahorses have filaments that resemble algae, while others specialize in sarcomatoid spines like gorgonians. They simulate the shape of their surroundings to camouflage themselves for deep lurk.
Seahorses is able to move their left and right eyes independently like a chameleon. They have 360° panoramic vision, which means they can keep one eye on passing zooplankton and the other on the lookout for nearby predators.
Seahorses have highly flexible tails. The cross-section of the seahorse's tail is square, giving it a high degree of flexibility and protection. Scientists in the field of mechanical engineering have discovered that the seahorse's tail, which has evolved over tens of millions of years, is not only highly flexible, but also protects the internal vertebra with the perfect coordination of muscle tissue and external bone. The discovery has inspired engineers who design and build robotic arms and robots.
Seahorses are the only fish in the world that swim upright, while other fish swim "on their stomachs". As seahorses are sedentary fish (they're indoorsy, to put it more politely), and they elude predators and catch prey by hiding in camouflage, swimming isn't their strong suit. Driven by dorsal and pectoral fins, they swim upright, beautifully and leisurely, which looks more like walking or dancing in the water.They get bullied by a lot of sea animals
Because seahorses are poor swimmers and have limited defenses, they become prey for many marine animals, including turtles, cormorants, rays, sardines and even humble invertebrates like crabs, shells and sea urchins.
In order to avoid being bullied and eaten, seahorses have three different strategies when confronted by predators - hiding, playing dead, and clinging legs. Look, they're pretty smart.
Seahorses are the most devoted fish in the world
Unlike most fish in nature, seahorses are usually strictly monogamous and have unique and complex mating behaviors and habits.
First of all, because seahorses are naturally sparsely distributed, with fewer than tens in a 100x100m space, it's not easy for an adult to find a suitable mate. If a pair of adult seahorses of comparable size meet in the wild, they will "dance" together and form a bond. For the next week or two, they met every day at the spot where they first met, usually at dawn or late afternoon when the moon was barely visible.
Van Look/Journal of Experimental Biology
In the quiet surroundings, the male seahorse and the female one will "dance" together, sometimes with their tails entwined like human hands, which is very funny and romantic. After forming a bond, the female seahorse swims into the water at the right time to mate, releasing eggs into her pouch, which are then fertilized and raised into young.
It takes about 9 to 45 days of gestation for the male to give birth to his pups. Usually, there are 2 to 2,000 pups per litter, but only a small percentage of them make it to adulthood.
Destined to roam since birth
Newborn seahorse pups, usually the size of mosquitoes, start to live on their own. Within 2 to 8 weeks after birth, they drift with the sea to reach new habitats.
In the process, they will "clump together", and catch some of the seaweed in the water layer with their tails. By using this form of hitchhiking, not only do they save energy (since they are still weak swimmers), but also they confuse predators. Despite this, a large percentage of the pups starve to death or are eaten by other animals (cormorants, penguins, turtles, tuna, etc.) during drifting.
What does the disappearance of seahorses mean?
Seahorses are strict on environmental quality, and only live in the sea areas with prominent water quality and relatively complex and healthy habitats, including seaweed beds, mangroves, coral communities as well as estuaries and lakes with good water quality.
A typical case is the H. coronatus, who is named for its well-developed crest and a species of seahorse only living in temperate waters. It was first recorded at the end of the last century in China (" Bohai Sea Fish Records " in 1994) and was found in Bohai Sea. However, no reliable source has proved that it was found again in the past ten years, which is likely to be closely related to marine pollution and overfishing in Bohai Sea. The disappearance of seahorses is a reminder of the deterioration of the marine environment.
The status of the seahorse population is worrying
Due to their low natural fertility and demanding habitat condition, the seahorse family is now under severe threat from overfishing led by bottom trawling and damage to the marine environment.
14 seahorses are currently known to be threatened on the International Union for Conservation of Nature (IUCN) list of endangered species. The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) officially listed seahorses as subject to strict international trade controls in 2004 - the first marine fish to be listed on appendix II of the convention.
The seahorse is not a horse, but a kind of fish that lives in the sea and named for its resemblance to a horse. At present, the classification of seahorse is still controversial worldwide. According to the classification system adopted by CITES, seahorse is the general name of species of Syngnathiformes Syngnathidae Hippocampus. Seahorses are widely distributed in temperate and tropical seas, and the IUCN recognizes 46 species in existence.
During the breeding season, female seahorses deposit their eggs in the male's ventral pouch, which is brood pouch. After receiving the egg, the male seahorse releases sperm to fertilize the egg and incubate the fertilized egg for 15 to 30 days. The pouch is rich in blood vessels that provide nutrients for the hatching of the fertilized egg. When the pups hatch, the male launches them out of the pouch.