Deep Sea Angler Fish
By: Aryn Eason and Kaitlyn Morley
Glowing Light: The most obvious adaptation that the anglerfish has, is the glowing bulb that hangs from the top of its head. Due to the lack of food that is readily available in the dark depths of the ocean the anglerfish has adapted to lure food in rather than seek it out. Female anglerfish are the only ones with this light.
Food: Anglerfish are distinguished by their extremely large mouths, which have teeth angled inwards. The angled teeth allow prey to swim inside, but not to escape, acting as a trap. Their jaws are also expandable, and they have an elastic stomach allowing them to consume prey of various sizes, this is a useful adaptation for the fish to have living in such a harsh environment.
Body: These fish must be able to survive in very high pressure, and they must also be adapted to handle extreme cold temperatures. As a result, many of them develop strangely compressed bodies, with organs and bones arranged in such a way that the high pressure of the ocean floor cannot hurt them. Some species of anglerfish have even developed pectoral fins which act like legs, allowing them to walk along the ocean floor. Given the deep waters in which they live and their relative rarity, this particular adaptation is rarely seen
Due to the vastness of the ocean and the low visibility at which the anglerfish lives, females have the ability to release powerful mate attracting pheromones into the water which males are able to pick up on due to very strong olfactory sensors.
The male anglerfish acts like a parasite that is used by the female for reproduction. The process of mating is a unique one to anglerfishes and is rarely found in nature.
When a male anglerfish reaches maturity it spends its whole adult life trying to find a female to mate with. It has well developed olfactory organs that help it pick up pheromones produced by the female. Males are very small in size compared to females and as a result are unable to eat, making their quest for a mate that much more important.
Smaller males attach to females by biting them and fusing their mouths to the body of the female. The blood systems of the male and female become connected allowing him to remain attached indefinitely. The male’s body degenerates overtime until he is completely dependent on the female and is used for nothing but his sperm. It is not uncommon to see multiple males attached to one female.
When the female anglerfish wishes to mate, she can trigger a hormonal state which forces the males to release sperm for fertilization.
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