Octopuses, squid, cuttlefish, and nautiluses are all of the mollusk class, Cephalopoda, translated to “head foot.” Ancient Cephalopods have been dated back to the late Cambrian period. Unlike other mollusks, cephalopods internalize and reduce their shells to cuttlebone in cuttlefish, pen in squid, and absent altogether in octopi. Cephalopods are found all around the world and inhabit marine waters from tropical to near freezing and from shallow to the deep abyss. Today, there are about 800 species of cephalopods. Cephalopoda has an intelligence unlike any other invertebrate. The mollusk class has been deemed the smartest of all invertebrates. In particular, octopuses have a brain-to-body mass ratio that is higher than vertebrates such as fish …show more content…
These particular invertebrates have been found to physically manipulate their environment by prey manipulation, burying and den excavation, arm dexterity, den barricading with rocks/coral. The observations of such behaviors have led scientist to believe cephalopods have the capacity to employ tools (Finn, 2009). Cephalopoda is also known for their body-patterning abilities for interspecific and intraspecific communication. The cephalopod skin has been deemed a very complex and sophisticated organ in itself. Cephalopoda skin colors and textures are regulated by intricate neuromuscular mechanisms. Chromatophores are the reason behind their skin appearance. Chromatophores are large pigment-containing cells distributed in the superficial layers of the skin over the whole surface of the body. By equal and unequal dilation of chromatophores, a variety of patterns and colors are produced causing the animal to become darker, lighter (Barbato, 2007). The Cephalopoda’s sophisticated development, their ability to learn, and the how they can physically manipulate their environment pronounces them the most intelligent …show more content…
This has yet to be seen in invertebrates until Cephalopoda. Octopuses have been observed carrying around potential tools and assembling them when needed. Until these observations, invertebrates have not been known to have such cognitive abilities that are needed to engage in sophisticated behaviors such as tool use. One particular octopus species, the veined octopus, has been known to use a specific tactic called stilt walking that allows them to carry coconut shell halves and use them to build shelter against predators. Complex cognitive processes such as planning, problem-solving, and environment manipulation are indicators of rational thought as well as tool use. This further enhances the Cephalopoda
Ceratopsians and Pachycephalosaurs Around 144 million years ago, began the emergence of the Ornithischian dinosaurs during the Cretaceous period and diversified into North America and Asia. Ornithischians were classified as having a hip structure similar to that of birds, although they are not the descendants of birds. Marginocephalians, meaning "fringed heads" are a group of Ornithischians that have a distinctive skull structure, consisting of a slight shelf or bony frill on the back of the skull, a unique palate, and a short hip structure. These herbivores include two major groups: the Ceratopsians and the Pachcephalosaurians. These plant-eaters include the Ceratopsians, horned dinosaurs such as the Triceratops, Styrachosaurus, Pentaceratops, and the Protoceratops.
One hundred and fifty million years ago, large aquatic species of reptile such as the Plesiosaur dominated the ocean, and were pre-eminent predators of the sea. The branch of now extinct Plesiosaurs, or ‘near lizards’, evolved into variant closely related species specialised to take different niches in the food chain. Such species of Plesiosaur include the phenotypically similar Plesiosauroid and Pliosauroid. The physiological adaptations of the long necked variant, the Plesiosauroid, as it relates to deep sea diving, will be addressed in depth.
Cephalopods are known to be exceptionally intelligent by invertebrate standards and in some respects even rival “higher” vertebrates. These animals have many highly evolved sensory and processing organs that allow them to gain a greater understanding of their environment and their place within it. Due to their advanced structures, many of which are analogous to vertebrate structures, and abilities they have been widely studied. Their methods of learning have been of prime interest and many experiments have been conducted to determine the different ways in which octopuses can learn. From these experiments four main kinds of learning have been identified in octopuses: associative learning, special learning,
The crustacean moult cycle is initiated when the Y-organ in the head secretes the hormone Ecdysone (E) into the circulatory system[3,4,5]; the Y-organ is the primary source of E[5]. Upon contact with the haemolymph (a combination of blood and tissue fluid) within the circulatory system E is converted to its active form, 20-hydroxyecdysone (20E), by a P450 enzyme[4]. This causes the epidermal cells to secrete moulting fluid, which contains a mixture of enzymes such as proteases and chitinases. The moulting fluid degrades the exo- and endocuticle, and the digested cuticle is reabsorbed to create new cuticle; moult fluid also has a role in initiating the moult. The degraded cuticle is replaced by water or air so that the animal can swell in order to lose the shell. During the passive phase of the moult cycle, the shell splits along the break point caused by the decalcification of the shell, in the crab this is along the epimeral lines. Once the shell has split, the animal wiggles side-to-side to free itself from i...
In the phylum Mollusca, there are many organisms that have body parts that change as the environment around them change; such as the octopus. An octopus can camouflage to variety of objects in its environment. Each organism in the Mollusca phylum has a type of foot that stows mobility and they eat by a radula. The radula is strap like tongue that has very sharp teeth and they can change to be different shapes or sizes based on their prey. They have a pseudo coelomate body plan, meaning that they have a coelom that exists, but it is lined by mesoderm only on the body wall, not around the gut. This video enhanced my understanding standing of the phylum Mollu...
The Pacific Northwest tree octopus is close to extinction! It needs our help, so please try to help it by reducing the amount of pollution you put into the air. It lives on the west coast of the Olympic Peninsula in North America. Their habitat is on the eastern side of the Olympic mountain range, close to the Hood Canal. (Lyle Zapato)
“The skin of amphibians is water permeable, well supplied with glands, and often colorful, with the colors and patterns of many salamanders and anurans rivaling those of brightly colored birds. It performs many functions. It protects against abrasion and pathogens, serves as a respiratory membrane, perhaps marginally so in caecilians, absorbs and releases water, provides some dry-land species during droughts with a water-loss-resistant cocoon, and through color change (in some species) a...
*It may move over the bottom of the aquarium tank with the tips of its
In the early 1800’s, a new discovery that left paleontologists in awe was the fossil finding of the immeasurable amount of species of reptiles, Ichthyosaurs. Greek for “fish lizards”, these fossils were found all over the world. Because these large aquatic reptiles migrated just as whales do today, paleontologists have had the amazing advantage of collecting fascinating bone fragments throughout the past 177 years. Ichthyosaurs swam the ocean life from about 245 million until about 90 million years ago- approximately the same time dinosaurs ruled the land. The earliest Ichthyosaur fossil findings were in parts of Canada, China, Japan, and possibly Thailand. Countless fossils came from coatings of limestone produced out of the ocean-floor ooze that was predominantly superior at preserving very well facts of the creatures it digested (Perkins 2).
Liubicich, D.M., et al. 2009. Knockdown of Parhyale Ultrabithorax recapitulates evolutionary changes in crustacean appendage morphology. PNAS 106 (33): 13892-13896
The early tetrapods were the first vertebrates to actually walk the solid earth. They began their conquest of land in the Paleozoic era around 360 million years ago. The question many paleontologists have been asking for a long period of time is whether the anatomy for locomotion on land was developed in water for swimming purposes, or if it was adapted after the creatures became terrestrial. Recent findings of fossils indicate that the transformations of the aquatic creatures happened underwater in order to help them survive in the changing world. When looking for answers, they had to examine forearm, hip, wrist, finger, and other bones, as well as the lungs or gills of the early tetrapod fossils. This information is critical in understanding the history and the process of growth and change. It aids in learning about human evolution.
When someone says the word octopus, an image of an eight legged invertebrate comes to mind. The body structure of a mature octopus is very interesting. Octopuses are extremely intelligent. They have excellent memory can use tools, and are great problem solvers. Only birds and mammals are known to be smarter. Each one of their tentacles, which are used for prying open clam shells, has two rows of suckers that can give them a pretty good grip. An octopus also tastes with its tentacles. An octopus’s third right arm, also called hectocotyli, is also its penis which a male octopus will use to mate at one or two years of age. The only part of an octopus that cannot move or squeeze through small spaces is its beak where it consumes food. This is used for biting and also breaking things apart. Did you know that octopi have three hearts? This is because these sea creatures have extra legs and three hearts are necessary for better bl...
Humans have only discovered less than five percent of the ocean, while the ocean makes up seventy percent of our world. Even though we have explored so little of it, we have found very interesting creatures such as giant squids, yeti crabs, and zombie worms. None of these animals are similar in any way, not even their habitats, appearances, or diets. However they use these factors to be able to survive in sometimes extreme conditions.
Fox, R. 2001. Invertebrate Anatomy OnLine: Artemia Franciscana. Lander University. http://webs.lander.edu/rsfox/invertebrates/artemia.html, retrieved February 13, 2011.
First of all, an octopus is a cellapod. Which means it has a soft body, and no bones. An octopus also has eight arms, large useful eyes, and suction cups. ( Octopuses and Squid, page 6 by: Tori Miller.) All of these traits are mostly used for hunting. Eight arms come in handy when your prey is fast and can get away easily, large eyes are useful when you need to see in the dark or the depths of the ocean, and suction cups are used when they need to grab hold of something.( Octopuses Squid, page 14.) ( National Geographic, Octopus Facts.) Octopuses have blue blood caused by copper and bag like bodies. When born they're 1/4 of an inch and don't rely on...