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Biology 202
2004 First Web Paper
On Serendip
Recently, researchers have discovered the existence of an extremely unique type of octopus. The species, known as the Indo-Malayan octopus, has the ability to alter its shape, form, and color pattern to mimic or imitate other sea creatures in order to avoid predation (2). The discovery of the mimic octopus is noteworthy because no other type of cephalopod is known to have impersonation abilities. The octopus is also not limited to one imitation. Researchers have observed up to eight different formations. The alternations occur depending upon the appetite, surrounding environment, and proximity of predators the octopus encounters (1). In analyzing the formations, behaviors, and predators of the mimic octopus, it is important to isolate the origins of this exclusive, and highly intelligent defense mechanism. Is this means of protection or evolutionary development, one that allows the cephalopod a better means of survival? Or is this the result of observed behaviors where the mimic octopus becomes aware of the relations occurring in the environment, and successfully imitates a species based upon their ability to subsist when dealing with dangerous predators?
The existence of mimic octopi is restricted to the islands of Indonesia, specifically off the coasts off Solawesi, and Bali (3). Surprisingly, the octopi have been viewed during the daylight hours, generally residing near sand tunnels, and holes (1). The octopi enjoy these mounds because they provide a significant source of food, including small worms, fish, and crustaceans. The octopus utilizes its arms to feel for prey, and then captures the food through the use of expanded webs. However, when the animal is attempting to hide itself from possible enemies, the Indo-Malayan octopus can transform itself into a variety of organisms, including fish, sea snakes, and anemones. If the octopus observes a cluster of damselfishes, it will change into a lionfish by swimming above the ocean floor, with arms extended beyond the body (2). The lionfish is known to possess poisonous spikes, which successfully deter the damselfish from preying upon the mimic octopus. Another possible transformation includes the sole fish. The octopus is able to propel itself in a similar manner by forming a leaf-shaped arm that moves it across the ocean floor effortlessly. The octopus's arms are also useful in impersonating the sea snake. Two arms are waved around to appear like a pair of snakes, while the other six are hidden from view. The octopus also changes its color and creates yellow and dark bands across the exposed arms. Other variations employed by the mimic octopus include the sea anemone and the jellyfish (3).
The phenomenal behavior of the Indo-Malayan octopus has left researchers wondering how this trait has developed, or been acquired by the animal. The ability has not been viewed in any other species of cephalopods, despite their lack of a strong internal or external skeleton, a body type ideal for imitations. The studies and observations of these animals within their habitat point to a wide variety of reasons, both evolution-oriented and behavior-oriented, which are responsible for the development of this talent. The Indo-Malayan octopus has been able to copy those animals known to generate poisons, such as fish with toxic glands, and anemone, and jellyfish known for their stinging powers. This characteristic appears to validate the behavioral influence of the octopus's capacity for imitation since the animal has isolated those species, which are known to contain toxins (4). The behaviorist theory is further authenticated by the sexual mate perspective. Researcher's have also explored the idea that the characteristics are not primarily for defense, but to attract sexual mates (2). The idea is that females are more likely to mate with those who have the ability to transform into a larger number of sea creatures. The problem with this theory is that both female and male octopi were able to show mimic mannerisms, even when isolated from each other. Impersonations have never occurred within the cephalopod species without the presence of the male. Therefore, the trait is much more likely to be something examined and observed by the species over a long period of time.
However, there is a considerable amount of evidence, which supports the idea of evolutionary development. The cephalopod species is known to have the ability to duplicate the surrounding environment, by creating colors and patterns similar to the background. For example, the reef squid has the ability to camouflage itself among a group of parrot-fish. Yet, none of these organism types can accurately mimic so many different types of sea creatures. Since the species has begun with the aptitude to emulate an environment, evolutionary theory would explain a new advancement in the area of predatory defense. The progression of mimicry is based upon an organism, which reveals innovative formations that have not occurred within the species before (7). The octopus has developed the ability to not only mimic surroundings, but mimic a number of other creatures. This dynamic mimicry gives the Indo-Malayan choices to cater their behavior toward specific adversaries. This also explains why this trait is such a rare occurrence. As more creatures obtain the ability to imitate, the less effective the trait will become when avoiding enemies. These predators will eventually become aware of imitation, and develop the ability to spot charlatans (2).
Evolutionary assumptions also help in explaining the relative toxicity of the mimic octopus. It is currently unknown whether the octopus is poisonous, and whether the level of poison changes with the alternation in appearance. Theorists assume that the mimic has the same potential for poison whether it physically is perceived as a lion-fish, or a sea snake. This is because the entire act of imitation reveals that the animal is engaging in predatory deterrence. It most likely that the octopus imitates in order to avoid encounters. It does not have the available toxins to truly be a danger.
The evolutionary theory seems to explain more of the octopus's behavior and development. If the assumption is made that the mimic octopus has obtained the behavior through instinctual means, then possible lines of inquiry include what probable advancements in mimicry will occur in the next thousand years, and what behavioral traits will predators develop in order to battle camouflage defenses? Is water a more encouraging environment for camouflage behaviors? Can the qualities found in the imitation of the octopus similar to the imitations that occur in cellular diseases, such as cancer? The support of evolution as a basis for the growth of mimicry merely provides a foundation for the direction of future expansion in the area since most of what is known of these octopi are conjectures.
1)ABC's News Article Homepage, General Article
2)The Royal Society Articles Server, Indo-Malaysian Octopus Article
3)National Geographic Website,General and Related Articles
4)News Scientist Website, General Article
5)Science News Website, General Article
6)For Romeo Website, Small Article with Good Picture
7)UniScience Website, General Article
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