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Duckbill Platypus
Jaime Garcia
Historical Geology
Spring 2006

†††††††††††††††††††††††† ††††††††††The Duck-Billed Platypus

†††††††††† The duck-billed platypus is a very unique creature in many ways.The platypus can only be found in one area of the world, Australia.Unlike other mammals, the platypus evolved very differently, and unlike any other animals found on Earth.The oldest platypus fossils date back to 100,000 years ago.The first platypus was discovered by European explorers in the 1700s.The name platypus literally means bird-nose in Greek (Wikipedia).The Europeans gave the platypus this name to describe the unique duck-like on their face.

In many ways, the platypus can be seen as a walking contradiction because they are an egg-laying mammal.The platypus is a member of the Monotreme order; this means that they platypus uses the same opening for reproduction and to eliminate waste, this opening is referred to as the cloaca (Wikipedia).

The platypus is a fairly small animal and males are typically larger than the females.The adult platypus is on average 45- 60 cm in length and weighs between 2- 4.5 pounds.In comparison to other mammals the platypus has a relatively low body temperature; for males it is 32* C (90* F) and the body temperature for females is typically 38* C (100* F).The body is covered with brown fur that is used as an insulator, allowing the platypus to remain warm while under water (Wikipedia).†† Grooming is very important to the platypus and as a result their fur is always in good condition.

The platypus has many distinctive body features that separate it from any other animals; they have a soft bill, webbed feet, a flat, wide tail, and males have a spur on the inside of their back ankles that contains a poison gland.The soft, rubbery-like bill of the platypus serves an essential purpose; the bill enables the platypus to search and locate its prey.The platypus is one of the few animals that use electro-perception to locate its prey; the bill is electro- sensitive and it can sense the body electricity of other animals (Wikipedia).Although its tail is similar in appearance to the tail of a beaver, the tail of the platypus serves a completely different function.The tail of the platypus is used to help it maneuver through the water, allowing the animal to steer while swimming; the tail is also used to store fat.The legs of the platypus are very odd because they resemble the legs of an amphibian much more than they do a mammal.The legs of the platypus are short and they stick out of the sides of the body, rather than underneath.Not much is known about the function of the poisonous gland; it is suspected that it is used to injure enemies or used when fighting for a mate.As a result of having a relatively low body temperature, the platypus has to resort to alternative methods of producing body heat.Body heat can be generated in two ways; the platypus can increase itís metabolism or it can use its blood circulation to carry heat to the areas of the body that need it most and reducing it in the areas where it is not as needed, such as the tail and bill (Agnew).

††††††††††† The platypus can be found throughout most of Australia, but always near running water.The platypus tends to prefer slow streams over fast moving water.Borrows are dug and serve as dwellings for the platypus.These burrows are often found on the banks of rivers and streams.A platypus burrow tends to be oval in shape and 4 Ĺ to 9 meters in length.It is highly unlikely to find a burrow that is below the water line because of the possibility of flooding.The platypus prefers a burrow that is hidden by vegetation so that it is out of plain sight.

††††††††††† The platypus tends to be a solitary animal, only coming together for the purpose of mating.The reason for their solidarity could also be because the platypus is a relatively shy animal, one that attempts to avoid confrontation whenever possible.

††††††††††† The platypus spends the majority of its day foraging for food because it has to consume a quarter of its own body weight each day (Wikipedia).During the summer season food is much more plentiful than any other time of the year, so the platypus will consume more in the summer and store the extra body fat to help sustain itself throughout the winter.The platypus dives down to the bottom of the river using its bill to dig and search for food; each dive typically lasts up to 40 seconds (Agnew).The platypus can make up to 80 dived each hour (Brilliantes).While swimming, the platypus closes their eyes, ears and nostrils.The bill of the platypus is used to sense the location of its prey.The platypus typically feeds on including insects, crustaceans, mollusks and other small vertebrates.After catching its prey, the platypus will wait until it has reached the surface to eat, storing the food in its cheeks until that time.The platypus lacks teeth, so it uses small horny pads to crush its food.

††††††††††† The platypus waits until it is two years old to begin breeding; for males this is because they do not begin producing sperm until that time.Mating for females is more random because they do not breed every year.Just like most other mammals, breeding season is typically in early spring.The platypus lacks the sexual organs that are common to most mammals; both males and females have a cloaca, with this opening the platypus is able to successfully have intercourse and reproduce.Little is known about the mating rituals of the platypus, except for that it occurs in the water.†† Approximately 12-14 days after intercourse, the female will lay 1-3 eggs; each egg is approximately 11 millimeters in diameter.The appearance of these eggs very much resembles that of reptile eggs.The female much incubate the eggs by using her underbelly and tail.This incubation period typically lasts between 10 and 12 days.The incubation period can be divided into three stages of embryo development.First, the embryo relies on the yolk sac for nutrition because it has no functioning organs.It is during the second period that the fingers and toes being to appear.Finally, in the third stage the egg tooth appears (Wikipedia).The babies are born with no hair and their eyes closed.After the eggs have hatched, the mother must nurse her young.The platypus lacks nipples so the young feed on milk that oozes from two ducts that can be found on the abdomen.Six weeks after the babies have left the eggs, they will begin to resemble a platypus more because they are beginning to grow fur and open their eyes.†† Within 4-5 months the mother must begin to wean her young so that they can leave the burrow, by this time the babies have reached 80% of their adult size and 60% of their adult weight (Agnew).Throughout this whole process the male is absent because they have no role in caring for the babies.

††††††††††† The duck-billed platypus is undoubtedly one of the strangest mammals found on the Earth today.It is an egg-laying mammal with webbed feet and bill.The explanation for why the platypus evolved so differently from any other animal will most likely never be known.All we can say is that is truly an animal that is in a class all by itself.†††††



Works Cited

Agnew, George. The Complete Platypus. 18 Nov 2005. 10 Apr. 2006††

Brillantes, Phil. Ornithorhynchus anatinus. Animal Diversity Web. 20 Apr. 2006

Gray, Roberta. The Duck-Billed Platypus. 20 Apr. 2006

Platypus. 30 August 2005. Natural Environment, Department of Primary Industries and Water. 20 Apr. 2006

Platypus. 15 Apr. 2006. Wikipedia. 16 Apr. 2006