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Report

Nevis Public School

Endangered Species

Report on the

Komodo Dragon

http://www.pathfinder.com/people/970310/features/images/dragon.jpg

Komodo Dragon

Common name: Komodo Dragon

Scientific name: Varanus Komodoensis

Kingdom: Animalia

Phylum: Chordata

Class: Reptilia

Order: Squamata

Suborder: Sauria

Family: Varanidae

Genus: Varanus

Species: Komodoensis

Animals

To be an animal you have to be multicellular and heterotrophic. (21) (18)

Reptile

To be a reptile you have to have lungs, scaly skin, and a special type of egg. They also have adaptions to help them live their entire life out of water. (18)

Chordates

Chordates usually posses a notochord which is a rod that extends almost total length of the body when fully developed. It acts as support. Chordates have to also have:

1. bilateral symmetry

2. segmented body including segmented muscles

3. three germ layers and well developed coelom (coelom - body cavity that is completely lined with mesoderm, mesoderm - middle primary germ layer in an embryo, germ layer - any of three primary layers of cells (ectoderm, endoderm, and mesoderm) from which the various organs and parts of the organism develop by further differentiation)

4. single dorsal hollow nerve cord

5. tail projecting beyond the anus in some stage if not all their life

6. pharyngeal pouches present sometime in their life (pharyngeal - having to do with or produced in the pharynx)

7. ventral heart (ventral - located on or near the belly of an animal)

8. complete digestive system

9. bony endoskeleton usually present (endoskeleton - supportive body structure located inside many mammals). (18)(14)

We could not find anything else on the classification.

Habitat

http://www.amnh.org/Exhibition/Expedition/Endangered/ora/map.gif

The Komodo dragon lives on a few small islands in Indonesia which are:

Komodo

Padar

Rintja

Oewada Sami

Gili Moto

and parts of Flores

These islands were pretty much uninhabited, but now they have become a huge tourist attraction. These islands are pretty rugged and mostly volcanic. The Indonesian islands are scattered in the Pacific Ocean. They stretch between Asia and Australia.

The habitat has open plains, some tree cover, very hot long dry spells where the ground temperature can be up to 130 degrees, and at times there will be a short monsoon season. The Komodo dragons will have a burrow inside their territory. They will sleep inside the burrow to maintain their body temperature. The rest of the day they will spend trying to regulate their temperature either in the direct sunlight or in some shade. (16) (17)

http://www.wcco.com/partners/mnzoo/komodo.jpg

Different names for the Komodo dragon and how they got them are:

Komodo Dragon - from the island of Komodo and basically fits the description of a dragon

Komodo Monitor - monitor means lizard and from island of Komodo

Ora - a name just for these specific animals

Penduga - a very old Ora; Grandfather Ora

Buaja Darat - native people call the Komodo dragon this name because it means Land Crocodile. (16)

http://www.torontozoo.com/97preview/exhibits/animals/komodo/komodographics/tall.jpg

Description

The Komodo dragon is a large crocodile-like animal with a slender mouth, and long tail. It has long claws and its feet look like our hands, but on the wrong sides so our pinkies are his thumbs. It has a brownish gray body with bumpy skin such as an alligator. It has two simple eyes on either side of its head, and one sensory eye in the middle of the top of its head. The sensory eye is to sense the different light that hits it. It uses this to also tell the time of year from the light of the sun. The sensory eye helps them to determine when to mate. It has four feet that are all approximately the same length.(16) He walks with them bent at the elbow, but when he runs he extends his feet and puts his tail straight up in the air.(19)(20) Its teeth are like a shark's and look like miniature saws.(16) They can get up to two hundred new teeth in a year. It has two nostrils, one on either side of the head, at the end of the mouth. Its ears are little holes on each side of the head, but the Komodo dragon is deaf. It has a yellowish forked tongue that helps it smell food. The Komodo dragon can get up to ten feet long and weigh up to two hundred pounds. The Komodo can also run up to fifteen miles per hour. (15) (16) (17)

The behavior of the Komodo dragon is that they live by themselves except to eat. They will gather in groups at times to feed on carrion (dead, rotten, or decaying animals). They do this so they will know one another a little bit better. This will help them later on to determine a mate. (16) Their saliva has 40 different bacteria and an anti-coagulant (keeps blood from clotting) in it. The Komodo dragon will bite its prey. The prey will run away, but will continue to bleed because of the anti-coagulant. The Komodo dragon will track it down to feed on it using their sense of smell. Within twenty-four hours of being bitten, the prey will get gangrene because of the bacteria in the saliva and die. (19) After the Komodo dragon is done eating, it will go through a cleaning ritual which includes licking their lips free from food, sneezing to get any food out of their nose holes that might have gotten stuck, and also wiping their face in the grass and leaves. (16)

Each Komodo dragon has a different territory which includes a core or where they have a burrow made, a hunting area, and a scavenging area. The size of their territory depends on how large they are and also their rank. They follow a hierarchy system which is basically a chain of command. The top animals will get the best territories and best feeding position. Top males will also get the best female for mating. They will leave from their territory, but will always return to the exact same spot. They will hiss, lash their tail back and forth, arch their back like a cat, and puff out their neck to warn others that this is their territory. If the trouble isn't settled peacefully, they stand up on their back legs and lunge at each other biting and causing wounds on each other. When one has had enough, it will run away. (16)

These animals are top predators so they don't have a different behavior for defense. (16) The behavior for mating is very different. Mating takes place during the spring. The male will circle the female flicking its tongue out against the female's face. He will then rub her neck and back with his chin, occasionally nudging her. The female might run away during this, but the male will follow and if she gives up, it is a signal to him that she accepts him. He will catch up and grab the female by the back of her neck in his mouth and will lightly rake his claws down her back. Before long she will lie down on the ground, he will climb on top of her and tuck his tail under hers and they will start to mate. He will put his tail under hers because that is where the hemipenes are in the male. (16) (17) The Komodo dragon will most often mate near the dead bodies of large animals because that is where most of the other dragons will meet. (16)

Some prey that the Komodo dragon eats is:

Seafood - They can dive up to six feet to search the ocean floor for any dead animals.
Birds - The female at the Minnesota Zoo loves birds including chickens.
Carrion - They can smell carrion up to five miles away! The Komodo will feed on this in large groups, it is the only time that they are together. Carrion is dead, decaying, or rotting meat. any other meat -

The Minnesota Zoo will feed their dragons anything from chicken to rabbits to rats and mice. They will eat insects, fish, reptiles, and mammals. The young will eat mainly insects and small lizards. The adults are able to swallow animals almost as big as themselves. It really depends on the animal to know what they would prefer. Mostly they prefer carrion to live animals so they don't have to work to kill it. For example the female at the Minnesota Zoo prefers birds to any other mammal. (16) (20) (22) (6) (3) (7) (14)

http://www.sallys-place.com/images/travel/asia/dinosaur/p1-1-closeup.jpg

Institutions	Males	Females	Unknown	Births
Atlanta	0	1	1	0
Audubon	1	1	0	0
Brownsville	0	0	2	0
Busch Tam	0	0	1	0
Cincinnati	1	0	2	0
Columbus	0	0	1	0
Dallas	0	1	0	0
Denver	0	1	3	0
Dreher	0	0	1	0
Fortworth	2	0	0	0
Ft. Wayne	0	0	1	0
Honolulu	1	1	0	0
Louisville	1	1	0	0
Lowery	1	0	1	0
Memphis	1	0	1	0
Metro Zoo	1	1	0	0
Minnesota	1	1	0	0
NZP	1	1	6	0
Pittsburgh	1	0	0	0
Pretoria	0	1	1	0
Rio Grande	0	0	2	0
Rotterdam	1	2	0	0
San Antonio	1	1	0	0
San Diego	2	0	3	0
Sedgewick	0	0	2	0
Singapore	2	3	0	0
St. Louis	0	0	1	0
Sydney	1	1	0	0
Tokyo	0	0	2	0
Toronto	1	1	0	0
Yulee	2	0	0	0
Totals	22	18	31	0

I got this from (14). This chart was last updated in June 1998.

Reproductive system

Almost all reptiles reproduce by internal fertilization. In all modern forms, except the tuatara, the male has an organ kept turned outside in, in the base of it's tail. It is everted through the opening of the cloaca during erection. In the tuatara, the transfer of sperm is accomplished by bringing the genital openings into contact, as in birds. This was probably the method used by the ancestral reptiles- it is clear, in any case, that the penis had a separate origin in turtles, crocodilians, and mammals on the one hand, and in lizards and snakes on the other.

Thus, male lizards and snakes have not just one, but a pair of hollow structures called hemipenes, which make up their copulatory organs. Located in the tail just behind of the opening of the cloaca, the hemipenes often gives the tail of the male a thicker, more gradually tapering contour than that of the female. And, in may species, the sexes can be distinguished by this difference. A groove that serves as a channel for the sperm extends from the opening of the sperm ducts, along the inner wall (which is the outer wall during erection ) of each hemipenis. The surface may be pleated or set with spines that keep it in place in the oviduct of the female during mating.

Either one of the hemipenes may be used, but only one. The hemipenes nearest the female is everted and protruded from the cloaca during erection, which is brought about by a combination of muscular action and distension of the walls with blood. (17)

In the wild, Komodo monitors will lay their eggs during the months of July through September. The eggs are oval and about two inches wide and four inches long with a parchment shell (parchment means a thin leathery type shell). The eggs are not hard like a chicken's, but smooth and elastic; kind of like a balloon, but filled with water. The eggs will hatch in April. The female will lay her eggs in a hole in the side of a hill. She will lay anywhere from one-half dozen to two dozen eggs.

Instead of laying all of her eggs at one time, she will lay a few at a time for a period of several days! She does not take care of her young, she will lay the eggs, and cover them with soil, and then leave them. The eggs will incubate for eight or nine months, longer than most lizards. Some dragons have grown at average of about eight inches in a year. They reach sexual maturity in five years. Up to a length of seven feet a dragon will remain slender in the body. From that size, growth in length slows down. The young have spots and stripes and look kind of like the adults. The young after they are hatched will climb up a tree so the elders in the community won't eat them. The young Komodos will eat small insects or small animals. (16) (17) (20) (15) (13)

Digestive and Excretory System

The mouth is where the digestion begins. As the food is being chewed by the teeth it comes in contact with the taste buds located on the surface of the tongue. Taste buds send messages to the brain about whether the food is sweet, salty, sour, or bitter. The teeth grind the food down until they swallow the food down the pharynx to the esophagus that is connected to the stomach. The esophagus is made up of rings of muscle. To swallow the food, the esophagus performs peristalsis which is the esophagus contracting just above the food to push it down. A thick ring of muscle called a sphincter is found where the esophagus meets the stomach. The sphincter acts like a valve allowing food to pass down into the stomach and not let it pass back into the esophagus. The food is now in the stomach. Now the food goes to the small intestine and from there to the large intestine then to the rectum and out the anus where it is deposited as feces. The liquid nutrients absorb out the small intestine to the blood stream. The blood then takes what it wants then sends the rest back to the kidnies. From the kidnies it goes to the ureter then to the urinary bladder where it is released in liquid form. (17) (18)

Circulatory System

The heart of a reptile consists of three separate chambers, left atrium, right atrium, and ventricle. These will all pump at once and work together. The circulatory system works in two loops. The first loop has oxygen poor blood going from the right atrium to the ventricle in the heart to the lungs through the pulmonary vein. Then, oxygen rich blood from the lung is transported back to the left atrium of the heart through the pulmonary artery. The second loop carries the oxygen - rich blood from the left atrium to the ventricle of the heart to the rest of the body through arteries. It then carries oxygen - poor blood back to the right atrium of the heart through veins to do the process over again. (18) (21) The ventricle is able to pump both oxygen-rich and oxygen-poor blood at the same time because of the number of folds found in the ventricle.

Respiratory System

All air enters the body through the nose or mouth. The air that goes through the nose enters into the nasal cavity. The cavity has a lot of arteries, veins, and capillaries which moisturizes the air. Then the air enters the pharynx which is located in the back of the mouth and serves as a passageway for both air and food. These passages provide a direct connection between outside air and some of the most delicate tissues in the body. These passageways filter out dust, dirt, smoke, and other contaminates in the body. The first filtering is in the nose. The nasal airways are lined with hair and kept wet with mucus. At the top of the trachea is the larynx, made up of several pieces of cartilage. Inside the larynx are two highly elastic pieces of tissue called vocal cords. When the muscles contract, they provide sound. From the larynx, air passes into the chest cavity where the trachea divides into two parts, a left and a right bronchi. Each bronchus enters the lung on its respective side. The lungs are the main organs of this system. The bronchi divides into smaller and smaller passageways. These then lead into smaller passageways called bronchioles. This muscle controls the size of the air passages. They continue to divide until they are finally alveoli which look like bunches of grapes. The alveoli consist of thin, flexible, membranes that contain an extensive network of capillaries. Capillaries separate a gas from a liquid. The gas is the air that they take in and the liquid is the blood. The job of it is to get clean, fresh air into the alveoli. (18)

Breathing

When a reptile inhales (take air in) their diaphragm moves down. When they exhale, (breathe out) it moves up to push the air out. Their ribs help this because they help to protect the lungs and diaphragm. (18) (17)

Nervous System

The nervous system receives and relays information about activities within the body and monitors internal and external changes. The cells that carry messages throughout the nervous system are called neurons. The messages are known as impulses because they are in the form of electrical signals. Neurons can be divided into three different groups by the way the impulses move. Sensory neurons carry impulses from sense organs to the brain. Motor neurons carry impulses from the brain to muscles or glands. And interneurons connect sensory and motor neurons and carry impulses between them. The largest part in a neuron is the cell body. The cell body contains the nucleus and much of the cytoplasm. Much of the metabolic activity of the cell takes place in the cell body. Spreading out from the cell body are little branches called dendrites. Dendrites carry impulses from the environment or other neurons to the cell body. There is a long fiber that carries impulses away from the cell body which is called the axon. This extends in a row of small swellings called axon terminals, which are located quite a bit away from the cell body. Neurons are the functional units of the nervous system but they do not act alone as individual cells. They are joined together to form the a complicated communication network. (17) (18) (21)

Skeletal System

In order to retain their form and shape, all living things need some way to support themselves. Like all vertebrates, the skeleton has some special kind of connective tissue (tissue that joins other tissues together) called bone. Bones, cartilage, tendons, and ligaments make up the skeletal system. The bones that make up the skeletal system have to support and shape the body as much as the internal wooden frame does a house. Bones protect the delicate internal organs of the body. Bones contain enormous reserves of minerals, especially calcium and phosphorus, which are important to many body processes. Bones are also the sites of blood-cell formation. Most blood cells are produced within the soft tissue in the bone. Each bone contains a tough membrane around the outside which is called the periosteum. Blood vessels pass through this carrying oxygen and nutrients to the bone. Underneath the periosteum there is a thick layer of compact bone. Running through the compact bone is a network of tubes called the Haversian canals. These contain the blood vessels and nerves. Inside the compact bone is spongy bone. Spongy bone is not soft and squishy as you would think from the name, however it is very strong. Near the ends where the force is the greatest, spongy bone is organized like supporting girders in a bridge. This organization of the spongy bone helps add strength without adding any more mass.

Embedded near the spongy bone are cells called osteocytes. These can either deposit the calcium salts in the bone or absorb them again. Osteocytes are responsible for bone growth and changes in the bone. Within the bones are cavities that contain a soft tissue called bone marrow. There are two different kinds of bone marrow: yellow and red. Most bones contain yellow marrow, which is made up of blood vessels, nerve cells, and fat cells. Red marrow produces red blood cells as well as some special white ones (lymphocytes) and other elements in blood (platelets).

Many bones are formed from the cells of connective tissue called cartilage. Cartilage does not contain blood vessels. Cartilage is dense and fibrous, can support weight, but is still extremely flexible. The bones when growing are replaced during ossification, the process of bone formation. (17) (18)

http://www.auduboninstitute.org/jpegs/z00_komodo.jpg

Conservation

Some conservation that is being done to protect the Komodo dragon is:

- Restricted trade.

- Komodos caught in the wild don't live well in captivity. They don't produce well enough and die or they will die from infections or diseases so the government is allowing only a limited number of Komodos to be captured and put into captivity.

- The island of Komodo in Indonesia has declared them a national treasure. They have put may restrictions on them. The only way a zoo around the world can get a Komodo would be to write a letter to the President of the island asking for one. He will only grant a few to be taken out of the country.

- Many Komodo dragons have been killed because they were thought to be fire breathing.

- Many were also killed because the Chinese thought that they could get swimming medicine from Komodo dragons. They thought this because the Komodo dragon is a very good swimmer and they wanted to save people from drowning.

- Legal protection has reduced hunting, but some are still killed to protect children and domesticated animals. (16)(3)