A New "Angle"—the Fish that Fishes
by | Nathaniel Nelson |
Looking like something out of a science fiction movie, the anglerfish uses a natural lure to draw its next meal nearer. The anglerfish's lighted lure glows with the help of millions of bioluminescent bacteria.
There are more than 200 species of anglerfish, most of which live in the murky depths of the Atlantic and Antarctic oceans, up to a mile below the surface, although some live in shallow, tropical environments. Generally dark gray to dark brown in color, they have huge heads and enormous crescent-shaped mouths filled with sharp, translucent teeth. Some angler fish can be quite large, reaching 3.3 feet (1 meter) in length. Most however are significantly smaller, often less than a foot.
( Above photo and notes from National Geography)
There are more than 200 species of anglerfish, most of which live in the murky depths of the Atlantic and Antarctic oceans, up to a mile below the surface, although some live in shallow, tropical environments. Generally dark gray to dark brown in color, they have huge heads and enormous crescent-shaped mouths filled with sharp, translucent teeth. Some angler fish can be quite large, reaching 3.3 feet (1 meter) in length. Most however are significantly smaller, often less than a foot.
( Above photo and notes from National Geography)
An impenetrable blackness enshrouds the angler fish as it floats near the sea floor. At a depth of 3,000 feet, none of the other fish can see the angler’s grotesque features. Its only appealing trait is a small lantern-like light resting on the top of a short stalk on its head. After having eaten a meal of shrimp or small fish, its stomach bulges out, resembling a basketball. Despite its gruesome features and intimidating appearance, it is only about the three inches long—roughly the length of a person’s index finger.
It is hard to imagine that nature could fashion such a fish in the midst of the darkest fathoms of the ocean. The angler’s framework is, for lack of a better word, weird. Ramsey Doran commented on the appearance of the angler fish.
Most deep sea anglers have soft, thin bones, jelly like flesh, and are either inky black or gray in color. It has been found that the red surfaces of deep sea prawns and the black surfaces of deep sea anglers reflect very little blue light. This means that if the other animals, the fish and prawns living at these depths, are giving out bluish lights, the black skin of the angler will render them invisible in the gloom, by absorbing any bluish light. Like many other fish in the deep, deep sea angler’s eyes are small. Most are shaped like a tennis ball with fins, and are not very fast. Unlike shallow water anglers, deep sea anglers do not have pectoral fins. Most don’t get very large and may grow to the size of a baby’s fist (2002).
One of the fish’s strangest identifying features is the bioluminescent “light bulb” on top of its head. Doran went on to make the following observation: “Millions of light producing bacteria cause the deep sea angler’s lure to light up. Only female anglers have the lure, and it is probably under her control. The female deep sea angler wiggles its lure from a long appendage on its forehead to attract its prey” (2002). This bobbing structure is, in essence, a fishing lure for catching prey.
The light that emanates from the appendage is produced by bacteria (Photobacterium luciferum) that, when congregated inside the angler’s “fishing pole,” produce a soft gleam. As the angler roves through the murky sea water, various fish—including dogfish, skates, cod, sprats, and flat fish—are attracted to the soft glow of its built-in death trap. Barbara Charton called this lure a “dorsal fin adaptation” (2001, p. 13, emp. added), as if it “somehow” had managed to come by the correct light-producing bacteria, while at the same time evolving an encasement for them.
When the angler manages to ensnare a fish, its inward-facing teeth will clamp down, ensuring that the victim does not escape. Its stomach is abnormally oversized and elastic, allowing it to ingest bigger fish. Imagine a large, spherical sac on the ventral surface of the angler, which can expand to accommodate fish nearly two times its size! What does evolution have to say to such prominent design as light-producing bacteria and elasticized stomachs?
The job of location a mate is difficult for sea life at the bottom of the ocean, because the lighting is so dim. Mark Norman explained how the male goes about finding the female: “She releases anglerfish-type perfumes into the water and he spends all his time swimming around looking and smelling for her” (2003). The angler fish counters this dilemma in a most unusual fashion. W.P. Armstrong put it like this:
Because angler fish are so sparsely populated throughout the vast millions of cubic miles of ocean, chance mating encounters between males and females would be unlikely. In fact, when deep-sea anglers were first brought up in trawls they puzzled scientists because they were all females. Then someone noticed small “growths” on the female that turned out to be the males. When a tiny male meets a female he bits [sic] into her flesh and literally fuses with her body. Like the linking together of web sites on the Internet, the two blood supplies also fuse together so that the male obtains nutrient and oxygen from the female. Without any need for most of his organ systems, such as eyes and digestive organs, the male’s body degenerates into essentially a pair of sperm-producing testicles. Thus the female essentially becomes a hermaphrodite with up to six or more of these tiny male parasites attached to various parts of her body. Although functionally bisexual, the eggs and sperm come from genetically distinct parents, thus providing genetic variability… (2004).
It is undeniable that the relationship between the male and female is extremely peculiar. From an evolutionary viewpoint, it is difficult to explain the relationship between these mating partners. According to evolution, at the supposed beginning of life on Earth, single-celled creatures utilized asexual reproduction as a means of continuing their species. In the depths of the ocean, where primitive life supposedly evolved into a larger populace of increasingly complex organisms such as fish, one would expect asexual reproduction to continue. It would be far easier to split in half, than to bring two different animals together in an inhospitable environment. This singularity would be emphasized to a greater degree near the dark ocean floor, where it is particularly problematic to find a mate. How, then, did the male and female angler fish survive without asexual characteristics? A male and female angler fish must be born; the male must find a female fish in total darkness; and the male fish must function as little more than a pair of testes. Evolution is obviously geared in reverse in this case!
The angler fish shows an idiosyncratic arrangement of parts that can only be explained by a Master Builder.
(This above article is originally from following link)
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