The Classification of Animals

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The Classification of Animals CONVERSATION I THE CLASSIFICATION OF ANIMALS Agosto, 2015 SANTA NATIONAL UNIVERSITY’S LANGUAGE CENTER. CEIDUNS MORALES CHORRES CYNTHIA STEFANY CHIMBOTE – PERU INDEX PÁG. I. INTRODUCTION……………………………………………………………… 3 II. ANIMAL’S CLASSIFICATION 1. DEFINITION……………………………………………………………….. 4 2. CLASSIFICATION 2.1. According to their structure………………………………………. 5-7 2.1.1. Vertebrate………………………………………………………. 5-6 2.1.2. Invertebrate…………………………………………………….. 6-7 2.2. According to their feeding………………………………………… 7-8 2.2.1. Herbivores……………………………………………………… 7-8 2.2.2. Carnivores……………………………………………………… 8 2.2.3. Omnivores……………………………………………………… 8 2.3. According to the way of reproduction…………………………….9-11 2.3.1. Oviparous………………………………………………………. 9-10 2.3.2. Viviparous………………………………………………………10-11 III. CONCLUSIONS………………………………………………………………. 12 IV. REFERENCES………………………………………………………............. 13 I. INTRODUCTION INTRODUCTION In the world there are thousands of species of animals, interact with us and contribute to the preservation of this large ecosystem called Earth. CONVERSATION I – CEIDUNS 2 They are all different: some fly, some walk, others crawl on the ground, some eat fruit and other eat other animals; are those that have a spinal column and those that don't have. Due to the large number of animals, and also due to differences between them, is that many scientists throughout history have tried to separate them theoretically in groups to can achieve a rating that allows the easy understanding to the learning and the research. Sort means group by shared categories: put in a same category or group, certain types of animals that share similar characteristics. Much so that scientists have studied each animal and have found the similarities between them to begin a classification. There are many different classifications according to the viewpoint that take, for example the type of food they eat, the type of place where they live, the type of skin they have, etc. And it should be noted that these categories aren´t exclusionary, that an animal can belong to more than one category, simultaneously. For example, can eat fruits and at the same time have spinal column II. ANIMAL’S CLASSIFICATION ANIMAL’S CLASSIFICATION 1. Definition : CONVERSATION I – CEIDUNS 3 Animals are classified in a variety of ways. This helps scientists to study the relationships in animal groups and to see the whole animal family tree as it has developed through time. The study of animal classification is called taxonomy. It is called animal of all live creatures that can move from one place to another. Animals require oxygen to live and some require other animals for food. The animals are formed by a set of systems, for example circulatory, nervous, and respiratory, digestive system, etc. 2. Classification: To classify a group of animals, first, we must find a common characteristic that allows us to separate into smaller groups. Then we will see a classification of animals according to three criteria: 2.1. According to their structure: 2.1.1. Vertebrates: The vertebrate animals have bones and spine. The body of vertebrates consists of head, trunk and extremities. Each class of vertebrate has its body covered of different form, mammals have hair; birds have feathers; fish and reptiles have scales; amphibians have bare skin. Between these there are: Mammals, Birds, Fish, Reptilians and Amphibians. CONVERSATION I – CEIDUNS 4 Animals with an internal skeleton made of bone are called vertebrates. Vertebrates include fish, amphibians, reptiles, birds, mammals, primates, rodents and marsupials. Although vertebrates represent only a very small percentage of all animals, their size and mobility often allow them to dominate their environment. CONVERSATION I – CEIDUNS 5 2.1.2. Invertebrates: With the name of invertebrates are known all animals that don’t have spinal column, although they have an internal or rigid skeleton. They have adapted to all possible forms of life from the seabed to the highest peaks. The main groups are Porifera, coelenterates, molluscs, annelids, arthropods and echinoderms. Of the million or more animal species in the world, more than 98% are invertebrates. Invertebrates don't have an internal skeleton made of bone. Many invertebrates have a fluid-filled, hydrostatic skeleton, like the jelly fish or worm. Others have a hard outer shell, like insects and crustaceans. There are many types of invertebrates. The most common invertebrates include the protozoa, annelids, echinoderms, mollusks and arthropods. Arthropods include insects, crustaceans and arachnids. CONVERSATION I – CEIDUNS 6 2.2. According to their feeding: 2.2.1. Herbivores: An herbivore is an animal that eat plants. In the food chain, herbivores are primary consumers. A herbivore is an animal that gets its energy from eating plants, and only plants. Many herbivores have special digestive systems that let them digest all kinds of plants, including grasses. Herbivores need a lot of energy to stay alive. Many of them, like cows and sheep, eat all day long. There should be a lot of plants in your ecosystem. 2.2.2. Carnivores: A carnivore is an animal that gets its energy through a diet, either through predation or consumption of carrion. A carnivore is an animal that gets food from killing and eating other animals. Carnivores generally eat herbivores, but can eat omnivores, and occasionally other carnivores. Animals that eat other animals, like carnivores and omnivores are important to any ecosystem, because they keep other species from getting overpopulated. Since carnivores have to hunt down and kill other animals they require a large amount of calories. This means that they have to eat many CONVERSATION I – CEIDUNS 7 other animals over the course of the year. The bigger the carnivore, the more it has to eat. 2.2.3. Omnivores: These animals eat all kind of food, because they prefer food of animal or vegetal origin. In addition to humans, other omnivores animals are: the pig and bear. An omnivore is a kind of animal that eats either other animals or plants. Some omnivores will hunt and eat their food, like carnivores, eating herbivores and other omnivores. Some others are scavengers and will eat dead matter. Many will eat eggs from other animals. Omnivores eat plants, but not all kinds of plants. Unlike herbivores, omnivores can't digest some of the substances in grains or other plants that do not produce fruit. They can eat fruits and vegetables, though. Some of the insect omnivores in this simulation are pollinators, which are very important to the life cycle of some kinds of plants. 2.3. According to the way of reproduction: 2.3.1. Oviparous: Oviparous animal form and develop inside of an egg that has been fertilized for the male of the species has been put by the female. Many animal species are born from an egg, these include birds, some reptiles like turtles or crocodiles, most insects, amphibians, most fish and some mammals known as monotremes, like the platypus. Oviparous animals are those that reproduce by laying eggs, with little or no embryonic development within the mother. This is the reproductive method of most fish, amphibians, reptiles, insects, arachnids, all birds and egg-laying mammals. Oviparous animals may fertilize their eggs either externally or internally. External fertilization involves the passage of the sperm to CONVERSATION I – CEIDUNS 8 the ova through an ambient medium, usually water. For example, frogs achieve external fertilization of their eggs during amplexus, when the male deposits sperm over the eggs as they are laid by the female. External fertilization in many aquatic invertebrates is less well controlled; for example, in the case of many marine invertebrates which shed immense numbers of gametes to the water more or less simultaneously, with ova and sperm meeting somewhat by chance. All animals that fertilize their eggs externally are oviparous. In cases of internal fertilization, male animals somehow pass their sperm into the female. For example, male salamanders deposit a sperm packet, or spermatophore, onto the bottom of their breeding pond and then induce an egg-bearing (or gravid) female to walk over it. The female picks up the spermatophore with the somewhat prehensile lips of her cloaca, and retains it inside of her body where the eggs become fertilized. These fertilized eggs are later laid and develop externally, representing oviparity. Many species of fish, most species of lizards and snakes, all species of crocodilians and birds, and even certain primitive mammals such as the platypus and echidnas achieve internal fertilization of their eggs through copulation. If the eggs are then laid to develop externally, the process represents oviparous. CONVERSATION I – CEIDUNS 9 2.3.2. Viviparous: Viviparous are animals that develop inside the uterus or womb which is an organ is in the female reproductive system and at birth, pass in and out through the vaginal canal. They are viviparous humans and all animals’ mammals, ie, that have a feeding with breast milk, like the lion, giraffe, bats, monkeys, etc. Is the retention and growth of the fertilized egg within the maternal body until the young animal, as a larva or newborn, is capable of independent existence. The growing embryo derived continuous nourishment from the mother, usually through a placenta or similar structure. This is the case in most mammals, many reptiles, and a few lower organisms. Viviparous animals differ from egg-laying animals, such as birds and most reptiles. Egg-laying, or oviparous, animals obtain all nourishment as they develop from the yolk and the protein-rich albumen, or "white," in the egg itself, not from direct contact with the mother, as is the case with viviparous young. The offspring of both viviparous and oviparous animals develop from fertilized eggs, but the eggs of viviparous animals lack a hard outer covering or shell like the chicken egg. Viviparous young grow in the adult female until they are able to survive on their own outside her body.
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