One of my favorite creatures under the sea is the Cuttlefish. Cuttlefish have some of the most unique features of the animal kingdom, and, like other cephalopods, are of interest to the origins debate. This being the case, this article will examine cuttlefish. We will discuss what they are, their special features, and where they fit in the ongoing origins debate.
Cuttlefish are Cephalopods, and are found in warm to moderately warm waters throughout the world, with the exception of the two Americas. The word “Cephalopod” means “head-foot”. The cuttlefish, with its tentacles protruding prominently from its head, fits this name to a “T”. Cuttlefish have a very short lifespan, of a mere one to two years. There are close to 120 species of cuttlefish found throughout their range, varying in size from a few inches to a foot and a half. Their most obvious feature are their tentacles, equipped with suction cups, just like their squid and Octopus cousins. However, these tentacles are used more for hunting prey than for locomotion. The cuttlefish moves using specialized fins on its sides. These fins keep it stable in the water column and provide basic movement in any direction. However, if frightened or threatened, the cuttlefish can jet away by rapidly forcing water out of its body cavity and thus propelling it the opposite direction. For rising or dropping in the water column, cuttlefish use a special internal, calcium fortified organ called cuttlebone. Riddled with pores, this cuttlebone regulates buoyancy by absorbing or expelling air.
Cuttlefish eyes are very special. They are formed in a “W”-like shape and are excellent at seeing contrasts. Though unable to see color, cuttlefish can easily detect differences in shading due to their ability to see light polarization, indicative of changes in color or shade. Due to water blocking ultraviolet light, cuttlefish are able to have their optic nerve behind the retina, rather than in front as in most land animals, removing the blind spot. The classic “W”shape of the pupil controls how intense light is when it enters the eye, helping prevent retinal damage. The eyes are massive for the size of the cuttlefish, and are quite good at detecting movement.
Cuttlefish are the ultimate masters of camouflage in the ocean. This is due to their incredible ability to change color to mimic just about any surface. They can change rapidly, sometimes in a mere second. These color changes occur for numerous reasons. The most obvious one is to hide from a predator, but cuttlefish also use them to hunt and communicate with one another, particularly during courtship. They change color so easily due to specialized pigment cells in their skin called chromatophores. Cuttlefish have been estimated as having up to two hundred of these chromatophores per square millimeter of skin. That high a density of chromatophores enables the cuttlefish to change its appearance drastically with ease. These masters of disguise can also use their muscles to change the texture of their skin, enabling them to sit on the seabed among the sand or rocks with equal felicity. In mating, males have been known to show an angry, dominant front to other males with one side of their body, while showing the female a calm, enticing front with the other. Some individual cuttlefish have displayed anywhere between 12-14 unique patterns, with several coming within seconds of one another.
Cuttlefish have a broad, varied diet. Usually it consists of crabs, shrimp and small fish, but anything else the cuttlefish can capture is fair game. Cuttlefish do not chew their food. Instead, they tear chunks off of it with their beak, which is buried behind their arms. To capture prey, cuttlefish sneak up on it using their incredible camouflage. Once in range, the cuttlefish fires a pair of specialized tentacles out from behind its arms. These two tentacles capture prey and draw it back into the beak of the cuttlefish where it is devoured. Sometimes cuttlefish will attempt to hypnotize their prey by rapidly changing colors. When the tables turn, and cuttlefish are being hunted, they have several natural defenses. They can jet away from a predator. They can change color to attempt to hide from an enemy, or, like the Octopus, they can secrete a cloud of ink and use it to cover their escape.
Cuttlefish reproduce towards the end of their life cycle. They lay specialized egg sacs, infused with ink to give them color and make them less obvious against the backdrop of the seabed. Males compete with one another for the females attention by posturing until one backs down. Once a male has won his mate, they will go through a brief courtship ritual and the male will transfer a sperm packet to the female using one of his tentacles. He will then guard her until she lays her eggs, which usually happens within hours.
Cuttlefish are amazing creatures and raise several interesting challenges to the prevailing evolutionary dogma. Cuttlefish produce ink, squids and octopii. Where did this ink originate from? Further, the system required produce this ink are irreducibly complex. The mechanism to produce ink, the storage compartment, and the ink jet all must be present for the system to work, and all must have come into being simultaneously, or none are useful. Then there are the chromatophores, which give the cuttlefish unmatched control over its appearance. They are complex enough to merit their own article. How did they arise? How did cuttlefish learn to control them once they had arisen? Why do cuttlefish have specialized hunting tentacles? Why did they evolve suction cups? Even something as simple as the eggs having ink inside raises the question why. How does a less than two foot long creature know to disguise its egg sac from predators using ink? Evolution has no explanation for the cuttlefish. Far better to believe that an all-knowing, all-mighty, all-powerful God created the cuttlefish to be exactly as it appears today, than to believe it randomly appeared as a product of blind chance.