Biological Adaptations
Taylah Rich 11MKL
Duck-Billed Platypus
Environment
The duck-billed platypus can be found in Eastern Queensland, New South Wales, Tasmania as well as eastern, central and southwestern Victoria. The platypuses natural habitat is in freshwater lakes, rivers, lagoons, farm dams and streams.
Most platypuses are found in water that has earth banks with roots, overhanging vegetation, reeds and logs which are suitable for constructing burrows. Platypuses inhabit temperate, tropical, terrestrial and fresh water. This species normally lives in water that is no more then five metres deep.
When they are not spending time in the water, the duck-billed platypus spends its time on the stream banks just above sea level in burrows.
Platypuses prefer to spend to their time immersed in substantial amounts of water or else resting in their burrows. In these environments the average air temperature doesn’t exceed 18-20 degrees celsius.
Figure 7: Platypus Distribution Map in Australia
Challenges Faced
As platypuses are extremely dependent on a freshwater environment, the largest threats to the species include habitat destruction, waterway pollution and land clearing.
The lifespan of the platypus is also in danger because the species is increasing being hunted by predators such as snakes, goannas, foxes, rodents, and birds of prey.
Adaptations
Physiological:
Platypuses have a body temperature of 32 degrees celsius which is significantly lower than other mammals. This allows the platypus to maintain its body heat for long periods of time before it drops and also means that heat loss is slow due to the low body temperature. During extreme cold weather, the platypus reduces blood flow to bare and extreme parts of its body. This keeps all the vital internal organs intact.
Benefits:
The platypus being able to maintain its low body temperature for long periods of time and restrict blood flow to certain part of its body allows the species to obtain warmth as well as cope with the physical conditions of its environment including temperature.
Behavioural:
Platypuses build their burrows in the soft riverbank. These burrows act a home as well as a place for the females to lay eggs. Platypuses are nocturnal creatures and usually only leave their burrows in the early morning and at night. Once a female platypus lays eggs the female incubates her eggs using her tail and stomach and rarely leaves the burrow.
Benefits:
The adaptation of digging burrows for eggs is influenced by the need for protection and safety of the eggs from predators
.
Structural:
The platypus has two different layers of fur. The first layer of fur is short and dense so that water is unable to get through to the skin, this is known as the under layer. The second layer of fur is longer and is able to get wet, however it acts as a water seal, which waterproofs the platypus’s coat.
The bill of the platypus aids it survival by acting as a tool for finding and mechanically digesting food. The bill of a platypus has electroreceptors, which aid the platypus through murky waters without the need for eyes or ears. As a platypus must close their eyes under the water, the species see in the murky water by sensing electrical currents created by their prey’s small muscle movements. The prey is then stored in special pouches behind the bill and is consumed after the platypus returns to the surface. The platypus sweeps its bill from side to side underwater 2-3 times per second in order to sift through the bottom of the riverbed and to pick up the electrical impulses from its prey.
Benefits:
The platypus picking up electrical impulses from its prey using it bill allows the species to secure food and nutrients in its environment. The platypus having two layers of fur help to maintain the species body temperature and cope with the physical conditions of its habitat.
Figure 8: Platypus Burrow
Figure 9: Large Platypus bill containing electroreceptors
Rhythmic Pattern
Duck-billed platypuses are typically active and hunting for food early in the morning and late at night as they are nocturnal creatures. The purpose of the platypus sleeping during the day and hunting for food at night it to protect themselves from predators. This rhythmic pattern allows the platypus to be awake when its predators are sleeping and be sleeping safely in its burrow when its predators are awake, reducing its chances of being attacked.
The purpose of these rhythmic patterns is to allow the platypus to protect itself from its predators.
Interesting Fact
Platypuses are among the few venomous mammals. The male platypus have a spur on the back of their hind feet that secretes venom from a gland.