REASON WHY PLACENTAL MAMMALS HAVE COLONIZED LAND, WATER AND AIR
Placental mammals are considered the largest group of mammal species. They are class of vertebrates animals, which is characterised by mammary glands. In females it produces milk to nourish their offspring .the placental animals are warm-blooded animal that can regulate their body temperature. This type of species also has hair and fur that they use to protect their skin against cold as their skin insulate. This placental mammal includes species such as elephant, whales, bats and farm as well as work animals. Also human are regarded as placental mammal.
Placental animal have colonise all the environment land, water, and air. Because they differ in the way of surviving as they do not share same diet and the environment. Some placental mammals are carnivore, herbivores while other is omnivores. They differ on diet and the environment they live in, some live in the aquatic environment, and while other live in terrestrial environment.
Placental mammals colonize different environment, because they can regulate their body temperature which enable them to adapt in any environment. Increase in metabolic process which is influenced by the food they eat helps them to have better adaptation in different environment. Some placental mammals live in the aquatic where there is a deep shallow sea which is colder than the terrestrial but because they can regulate their body temperature, they are surviving. While other are surviving in the Iceland where it is cold
Some of the placental mammals can survive in both environment, this happens when other go to aquatic environment for reproduction, while other from aquatic to terrestrial environment to lay eggs, so this shows that they can adapt various climate change that happens as in the water is cold and in terrestrial there is fluctuation of temperature. because they can moderate their temperature they find it simply to adapt.
Different mode of locomotion also encourage the placental mammals to colonise many environment, some mammals are quadrapedal ,animal that use four limbs to walk .while other are bipedal they use two limbs movement. Most of the species that uses limbs for movement survive on land than in water this because they choose diet which is abundant on land. Whereas species that are found in aquatic environment they use fins to float.
Placental mammals colonize the most habitant because the can move and they can regulate their body temperature. Also the diet they feed on is found in all environments. Because most of the endothermic process that mammal species have it helps them to adapt in any environmental condition. This occurs because they can regulate their body temperature, when the environment is not conducive to them.
In nutshell placental mammals are warm-blooded animals that can regulate their body temperature and they have different mode of movement helps them to colonise any habitants as they can adapt. The diets they have chosen also enable them to colonize most of the environment.
Reference:
1. Hastings.L. Mammal Adaptation.[Internet] [cited 2006-May-11]Available from: http://animals.about.com/cs/mammals/a/mam101ab.htm
2. Mammal, [internet] [cited 2006 may 8]. Available from: http://encarta.msn.com/encyclopedia_761561349/Mammal.html