Sample Biology Paper on Adaptation of Amazonian Manatee

Adaptation of Amazonian Manatee


Amazonian manatee is a marine mammalian species that is mainly found in the Amazon Basin and the Northern South America. In the past, they lived in large herds. However, constant poaching and overhunting of the Amazonian manatee has resulted to a significant reduction in its population leading to their extiction. One of the main species of the Amazonian manatee is known as Trichochus inunguis. Trichochus inunguis is regarded as the smallest among the three species of Amazonian manatee. This species is characterized by grey to black color, smooth skin and thick bristles on the lip pads of both jaws. In addition, this animal has cryptic and secretive behavior as they can be rarely seen by man who continues to pose a threat to the mere existence of the animal as a result of overhunting.


Trichochus inungus is known to reside primarily under water in lakes, oxbows, lagoons and blackish waters. This animal species mainly inhabits areas of calm, shallow waters that is relatively away from the human settlements. They are mostly found in lowland tropical areas that are usually below 800 m above sea level. In Amazonian rivers, they can be found in either white, black or clear sections of the river. They live well under warm waters with temperatures ranging from approximately 220 C and above. Most of the Trichochus inungus residing in the Amazonian rivers are usually found in the white part of the river that is predominated by vast aquatic vegetation.  Trichochus inungus are able to survive and live under water as they protrude their nostrils to the water surfaces for the sole purpose of breathing. They are also known to have the habit of migrating from one given place to another as determined by the different weather and climatic seasons. During the wet seasons caused byheavy rains and floods, this species of animal would migrate from flooded areas to shallow waters for the purposes of breeding. This usually takes place during the months between February and May which is usually characterized by a significant increase in water levels due to the wet season. On the other hand, most of these animals would migrate from shallow waters to the deep waters during the dry seasons.


Trichochus inungus are regarded as herbivorous as they primarily feed on aquatic vegetation. They can mainly be found in lowland tropical areas which are characterized by vast growth of both aquatic and semi-aquatic plants.  In a day, this species of animal is able to eat aquatic vegetation that may be up to 8% of its body weight. The feeding cycle of this animal species is also determined by the weather and climatic seasons. Most of the feeding takes place during the wet seasons of the year where both the aquatic and semi-aquatic vegetation are in abundance. However, during the dry seasons, most of these animals would migrate to deep waters which are characterized by the absence of the aquatic vegetation. It is with this profound reason that this animal species would not feed for weeks during the dry seasons of the year.  Some of the common aquatic vegetation that Trichochus inungus feed on includes; water hyacinth, grasses, water lettuce (Pisticia) and floating palm fruits.

Adaptation to its environment

Trichochus inungus are known to spend their entire life residing under water.  Therefore, in order for these species to survive in water, it has to have vital adaptations that are necessary for its survival. The manatees are known to breath in oxygen by exposing their nostrils to the uppermost surface of the water body. In order for these animals to ensure that they have sufficient oxygen levels, they need to have a reduced heart rate. This will essentially enable the marine mammal to save the on their oxygen levels. When these animals need to take breath in, they will rise to the surface of the water after every four minutes so as to take in oxygen. The animal can also stay for approximately 20 minutes underwater so as to reduce the rate of heartbeat and in turn save the oxygen. Trichochus inungus is endowed with two lungs which it uses for air circulation and gaseous exchange. However, when it comes to the respiration process, the animal does this via the noses only.  Furthermore, the manatees are able to renew approximately 91% of the air in their lungs by just one breath. The animal can thus be able to stay underwater for a long period of time.

The manatee is endowed with pectoral flippers which it uses to gather a mass of vegetation thereby directing the food (vegetation) to its mouth in a spoon-like manner. The manatees are also known to possess a layer of body fat which keeps it insulated from the low temperature or cold waters. Thus, this animal is able to survive the extreme cold seasons as the thickness of its body fat is dependent on the extent of cold temperature in that given environment. In addition to this, the Amazonia manatee is endowed with hemi-diaphragm that allows the lungs to switch out air independently. Hence, in any case the animal suffers from being struck by a passing yatch, the manatee can still be able to utilize the hemi-diagrams for gaseous exchange.


The following is a food web describing the feeding habits of Amazonian manatee, Trichochus inunguis.