Favorite Organism: Elephant - Research Paper Example

?Favourite Organism: Elephant Introduction Elephants are large animals. They mainly live in South Asia, Southeast Asia and sub-Saharan Africa (Fowlerand Mikota, 2006). They have several distinctive features when compared to other mammals. They have a long trunk, also known as proboscis which serves several purposes including grasping objects. Their incisors grow enormously and are known as tusks. These tusks are used as weapons and also as tools for digging and moving. The ears of an elephant are very large and have large flaps. These play a role in controlling the temperature of the body. Elephants are on the crux of becoming endangered species. Their physiological characteristics are different and interesting. In this essay various aspects of elephants will be discussed. Taxonomic classification The family to which elephant belongs is Elephantidae. It is the only family under the order Proboscidea. The domain is living, kingdom is Animalia, phylum is Chordata and class is Mammalia. Under the family Elephantidae, there are 2 genuses and they are Loxodonta or African Genus and Elephas or Asian genus. There are 2 species: africana or African species and maximus or Asian species. The subspecies in the former are africana and cyclotis and in the later are indicus, borneensis and sumatranus. Elephants are the only living members of the Proboscidea order (Fowler and Mikota, 2006). Description of the organism Elephants are mammals. The two main species are African elephant and Asian elephant. Extinct species of the order Proboscidea are mastodons and mammoths. Currently, elephants are the largest living terrestrial animals. A male elephant can reach a height of 4 m and can weight upto 7000 kg (Fowler and Mikota, 2006). African elephants have larger ears and backs that are concave. On the other hand, Asian elephants have smaller ears and backs that are convex. Other than these, African elephants also have more wrinkled skin, couple of extensions from the tip of the trunk which appear like fingers and a sloping abdomen. The lifespan of elephants is about 70 years. Elephants communicate through sound, touch and sight. For long distance communication they use seismic and infrasound waves. Their intelligence levels are comparable with primates. They have self-awareness and have empathy towards dying individuals. The Asian elephant is considered endangered and the African elephant is considered as vulnerable. These animals are poached for their tusks because of their ivory value. Elephants are also at threat because of habitat destruction and conflicts with people in the local region. In Asia, these animals are used for heavy work. They are also displayed in circuses and zoos. They are also featured in ceremonies and cultural events. Asian elephants have smoother skin, only one extension at the tip of the trunk and their abdomen is horizontal. The molars have narrower looped ridges in the Asian elephant when compared to African elephant which is diamond shaped (Shoshani, 2005). Other than these features, the Asian elephant has dorsal bumps on the head and also some depigmentation patches. Status of the organism The Asian elephant is on the crux of becoming endangered because of severe poaching on the animal for the purpose of tusk. Ivory can be derived from the tusk and it has a very good commercial value. Ivory is used to make different ornaments and objects. The leather of the elephant is also used for several purposes. African elephant on the other hand is not endangered but is called vulnerable (Fowler and Mikota, 2006). Unique physiological characteristics The word elephant is derived from the Latin word "elephantus". Of all the terrestrial living animals, elephant is the largest. The height of an African elephant is about 3-4 meters and that of an Asian elephant is 2- 3.5 meters. The former weighs between 4000- 7000 kgs and the latter weighs between 3000- 5000 kgs. Males are larger than females. The skeleton of an elephant has 326- 351 bones (Fowler and Mikota, 2006). The flexibility of the backbone of an elephant is limited because the vertebrae are connected by very tight joints. The elephant has 19- 21 ribs. The skull of an elephant is strong and resilient. Brain is protected by various arches of the skull. The skull has sinuses which reduce the overall weight of the skull and give the skull a honeycombed appearance. Neck is short. A nictating membrane protects the eye globe. Elephant does not have a lacrimating apparatus. Instead, it has a harderian gland that keeps the eyes moist. Elephants can see well in dim light but not in bright light. This characteristic feature helps the animal watch well in forest too. Elephant has 26 teeth (Shoshani, 2005). The teeth are replaced through rotation all their lives. The incisors are modified as tusks which have commercial value and the animal is poached for that. Teeth help in grinding the vegetation eaten. The flaps of the ears are large and contain many capillaries. Excess body heat is lost through these flaps. The skin is rough and about one inch thick, especially on the back and some parts of the head. More often than not, it is grey in color. Some African elephants may be brown in color. The trunk is basically the fusion of upper lip and nose. In early fetal life, both these are separated. Trunk is the most versatile appendage in an elephant. It has both superficial and internal paired muscles. The trunk performs multiple functions like touching, grasping, smelling, breathing and production of sound. It can perform powerful coiling and twisting movements and can lift upto 350 kgs. It can reach items upto 7 meters distance (Shoshani, 2005). The trunk can suck water for the purpose of drinking and also for the purpose of spraying. Trunk can be used as snorkel when the animal is underwater. Elephants are herbivorous and eat twigs, bark, roots, fruit and grass. They can eat 150 kg of solid foods and consume 40 liters of water a day (Shoshani, 2005). They feed in the morning, afternoon and also in the night. They can sleep while standing. They prefer to rest under trees during afternoons. They however, sleep mainly in the nights and during that time the animal lies down. They move about 10-20 km in a day (Turner, 2005). They migrate seasonally for mates, food and water. Elephants are known as keystone species because they have a huge impact on the environments due their huge size. They can uproot tress, they can dig waterholes which can be source of water for other animals too, they can excavate caves used by other animals, can defecate seeds which can germinate and other such environment related activities (Shoshani and Eisenberg, 1982). Their dung is not completely digested and hence is a food for other animals. Due to their weight, rain water can be runoff leading to erosion (Turner, 2005). Elephants are social animals. Females always live in family groups of atleast 10 that are matrilineal. Each group is led by the eldest female known as matriarch and she remains the lead of the group until her death. When male elephants move in groups, they show dominance hierarchy based on age , size and sexual condition. Male and female elephants come together only for the purpose of reproduction. Adult males enter into musth, a period of increased testesterone levels during 15 years of age and this is when they can start mating. However, most of them start mating by 25 years of age (Turner, 2005). The animals are aggressive during this period. Elephants are polygynous breeders and copulate mainly during wet season. Readiness to mate is indicated by pheromones in the urine of a female elephant. This triggers the male to follow her and assess her state by collecting a chemical sample with his trunk. The period of gestation is 2 years and intervals between 2 births are 4-5 years (Turner, 2005). Twinning is rare. For the first few days, the calf is completely dependent on the mother and only the mother takes care of the calf. Later, in family groups, other female elephants also take care of the calves. Milk is the only source of nutrition for the calf for the first 3 months after delivery (Fowler and Mikota, 2006). Elephants greet each other by wrapping their trunks and stroking at each other. They threaten by raising their heads and also by spreading their ears. Purpose of choosing this particular organism As a child, I always loved watching an elephant. Infact, I would always pester my parents to take me to a zoo or circus to watch an elephant. I loved the size of the animal and the way it coiled its trunk and pulled things. I always felt it was magnanimous. Despite it being such a huge animal, it dwelled only on leaves and twigs unlike other wild animals which are carnivorous. It is a mammal and takes care of its babies and leads a social life, similar to human beings. This essay writing is an opportunity for me to explore more about this organism and enhance my knowledge about it physiological characteristics and various types in the world. Conclusion Elephant is the largest living terrestrial animal and has distinct physiological characteristics for survival. Special features of the animal are its trunk and tusks. The animal is a social being and moves in groups. It is frequently poaches and this is a threat for its existence. References Fowler, M.E., and Mikota, S.K. (2006). Biology, Medicine, and Surgery of Elephants. NewYork: John Wiley & Sons. Shoshani, J.; Eisenberg, J. F. (1982). Elephas maximus. Mammalian Species, 182 (182), 1–8. Shoshani, J. (2005). Order Proboscidea. In Wilson, D. E.; Reeder, D. M. Mammal Species of the World: A Taxonomic and Geographic Reference, Volume 1 (3rd ed.). Johns Hopkins University Press. pp. 90–91. Turner, M. (2005). Asian Elephants. London: Heinmann Lib Read More