Lungfish+(fossil+-+Dipterus)

lungfish (modern) Lungfish (future - Katsuladon)

Dipterus, literally meaning ‘two wings’, is an extinct species of the modern lungfish from the late Devonian period of Australia and Europe. Dipterus was about 35cm in length, which resembles to the modern lungfish. It had tooth like plates instead of real teeth. Their fins were also separated. They had a primitive lung, which gave them the ability to breathe atmospheric air. Like many prehistoric fish, the head of the Dipterus was protected from predators by a tough and bony armor. Their tooth plates were adapted to help them crush shell fish. Unlike modern lungfish, the lungs of the Dipterus are practically useless, which means it probably spent more time underwater than its modern descendants.
 * __Fossil Animal: Dipterus__**
 * __Scientific Classification__**
 * **Kingdom: ** || Animalia ||
 * **Phylum: ** || Chordata ||
 * **Class: ** || Sarcopterygii ||
 * **Subclass: ** || Dipnoi ||
 * **Order: ** || Dipteriformes ||
 * **Family: ** || Dipteridae ||
 * **Genus: ** || Dipterus ||

Dipterus is the ancient ancestor of the modern lungfish which lived around 380 to 360 million years ago mostly in Australia, North Africa and Europe. The Dipterus has very similar structures to the modern lungfish, such as the skull, the pelvic and pectoral fins and their lungs. Interestingly, the Dipterus were only about 35cm in length which is smaller compared to today’s lungfish.
 * __Habitat__**

Unlike modern lungfish, the Dipterus preferred deeper waters than shallow waters for hunting and living. Very differently from today’s lungfish they do not have a choice. Plants grew under water over 5 metres millions of years ago, especially in Australia where they mostly lived. Due to drought, there was hardly any vegetation in shallow waters. This forced many habitats including Dipterus to live in deeper area, resulting in large sums of extinction. The Dipterus lived on the bottom of bodies of freshwater, because of the wide range of food and vegetation, the Dipterus found it an appropriate environment for mating. The Dipterus likes to mate in vegetation as the thickness of it helps keeps the eggs protected and hidden from predators. Being a small aquatic animal, it is very important for the Dipterus to be safe and out of sight of huge sea monsters such as the Dunkleosteus. Most marine animals where the Dipterus lived where preys of it, however, there are still some predators of Dipterus and this is why aquatic vegetation is necessary for the Dipterus. The Dipterus share similar habitat to the Micraster Corbovis, the ancient sea urchin. They live in similar lakes and oceans and were 'neighbours' for a long time for millions of years.
 * [[image:Snapshot_1_(6-7-2011_10-14_AM).png]] ||


 * __Adaptations__**


 * __Structural__**

An environmental pressure that caused this adaptation was the increasing predators around the area of habitat of the Dipterus.
 * __Head Protection -__** the Dipterus’s head was highly protective as it had hard bones protecting the eyes and mouth of the animal. The Dipterus has strong plates around the face which contributed to the armoured skull and protectiveness of the fish. It is quite effective against predators, especially younger ones which were often targeted.

An environmental pressure that caused this adaptation was the change in the variety of food. The Dipterus most likely seek shellfish as their primary prey due to the lack of their usual flesh for diet. This contributed to the tough plates.
 * __Tooth Plates –__** The Dipterus has tooth plates as well as strong jaws around its cheeks. This helps them to crush food and eat. Interestingly, the Dipterus loves the chew food in their mouth thoroughly, which is very uncommon among other fishes.


 * __Behavioural__**

An environmental pressure that leads to this adaptation was that small fishes were eating the eggs laid in the edge of shallow waters therefore Dipterus had to seek for a more protective habitat to lay their eggs.
 * __Use of surrounding vegetation –__** the Dipterus is small compared to other marine animals; this is why Dipterus seek thick vegetation to help protect themselves from predators. Also, the Dipterus uses deep water vegetation to lay their eggs instead of at the edge of the waters. This kept the eggs out of harm’s reach and has a greater chance of survival.

An environmental pressure which led to the adaptation of Dipterus living in the oceans is because of severe droughts that occurred in lakes and rivers of Australia. This forced the Dipterus to change its environmental and habitat to find a more suitable place for living.
 * __Surviving in the oceans –__** over thousands of years, many lakes and rivers had dried out in Australia resulting marine animals under threat of dying from drought. This also led to the mass extinction of aquatic life in Australia. Some freshwater fish including the Dipterus are able to rely on their instincts and swim towards the ocean. This helped them to survive the severe droughts.


 * __Physiological__**

An environmental pressure that led to this adaptation was the change of the environment. As the Earth heat up, drought occurred and this made the Dipterus to develop lungs which helped them to survive.
 * __Ability to breathe –__** with the primitive lungs, the Dipterus is able to breathe atmospheric air. Unlike modern lungfish which only has one lung, the Dipterus has two. Since the Dipterus lives in deeper pools their lungs are rarely used, this is similar to the modern Australia lungfish who only breathes air only one per hour. This is a very important adaptation because it helped the Dipterus to survive under severe drought.

Many things contributed to the extinction of the Dipterus. A pressure that led to this fish’s extinction is the change of habitat or environment. Drought occurred which forced the Dipterus to migrate to the ocean. However, because the Dipterus loves to live in waters where there is vegetation, the ocean cannot provide them with this requirement, and this led to loss of protectiveness for the Dipterus. Many large sea monsters including the Dunkleosteus was a predator of the Dipterus, with little protection in the ocean, the Dipterus quickly vanished from the ocean either from being eaten or died during the drought. Eggs were not protected from the predators and so the babies had little chance of survival and this led to the extinction of the Dipterus.
 * __Why did they extinct?__**

- Designeranimals. (2011). //Dipterus (Fossil).// Retrieved on 25th of June 2011. http://designeranimals.wikispaces.com/Dipterus+%28Fossil%29 - Wikipedia. (2011). //Dipterus.// Retrieved on 25th of June 2011. [] - Fossilmuseum. (2009). //Dipterus Devonian Lungfish Fossil.// Retrieved on 25th of June 2011. [] - Britannica. (2011). //Dipterus.// Retrieved on 25th of June 2011. [] - Dinosaursabout. (2011). //Dipterus.// Retrieved on 25th of June 2011. []
 * __Bibliography__**