CHARACTERISTICS OF ORDER OF PLACENTAL MAMMALS AND LISTS OF ANIMALS REPRESENTING EACH ORDER.

Placental mammals contain different types of orders. They are twenty orders. These orders include: Chiroptera, Carnivora,Perissodactyla, Cetacea, Artiodactyla, Dermoptera, Hyracoidea, Insectivora, Lagomorpha, Macroscelidea, Primates, Proboscidea, Rodentia, Scandentia, Sirenia, Condylarthra, Afrosoricida, Tubulidentata, and Xenarthra. Each order consists of different animals. They are also differs in terms of characteristics. "These animals hold their young within the mother until development is well along"(2).

The order Chiroptera is found in placentalmammals. These are only mammals that are truly fly and well furred bodies. Animal that fall under this order have very poor vision. These animals have wings, and they used those wings for flying purpose. They also eat insects and vegetation. Animal which are found in the order Chiroptera are bats.

Carnivora are another order of placental mammals.Carnivora are strictly meat eaters. Carnivora are large in size. Although Carnivora have heavy skulls. They all have hair in their bodies. The teeth of these animals are well developed. However all carnivores have sharp canine’s teeth. All Carnivora have simple stomach. The eyes of Carnivora are facing front. Dogs, bears, raccoons, seals, walrus and sea lion are the animals that are found in order Carnivora. http://www.nhptv.org/Natureworks/mammalia.htm

The order Perissodactyla have hooves. They are odd toed, meaning that they are unpaired. They are hoofed. Animals that fall under Perissodactyla have no gall bladder. All Perissodactyla are large animalsnot small animals. One can say that, animal fall under this order have complete set of incisors. It has longer skull. However these animals do not have true horns. Animals which are found under Perissodactyla are Horses, Rhinos, Tapirs, Zebras and donkeys.

Cetacea is one of the order of placental mammals. The body of Cetacea are fairly robust. On top of the head are open. Animals found here are warm blooded animals and they have few hairs on their bodies.” organism or animals which belong to this order are usually have the following characteristics, large body size, bubbler, usually hairless, sensory abilities such as large brain and they are good in swimming. These are the animals such as whales, Dolphins, Porpoises”.(5)

The orderArtiodactyla have four chamber stomachs. They lack upper incisors. All have long limbs. Many Artiodactyla have horns that grow from frontal bones of their skull. These horns are not the same as those of Perissodactyla.
The order Artiodactyla includes deep, pigs, cattle, goats, giraffe, camels and sheep. The toes of these animals are covered by large honey hooves.

The order Dermoptera has only one family having two species. Although these species are flying lernurs like squirrel, and Colugos. Their arms are covered by flap skin. They also have well- developed gliding membrane. According to the skull of these animals are unique.

"Insectivora is found on order of placental mammals. Inscetivora are insects eaters. These are animals such as Moles, Shrews and Hedgehogs. Many of Insectivora have poor developed eyes, and small ears. They use hearing and smell to find prey"(2).

Animals that found in the order Lagomorpha have long ears. They also have short tails. Its back legs are strong. They have two pairs of incisors. However these animals have no canine teeth and molars but they have spongy bones in the upper jaws. Animals that are found here are Rabbits, Hares and Pikas. It has short tails.

Macroscelidea is one of the group of placentalmammals. Animals that are found under this order are Elephant shrews. Their back leg is long. They also have big ears and eyes. Their tails are short.

Primates is one order of placental mammals. Lemurs, monkeys, marmosets, apes and human are found under this order. They also have forward facing eyes. However in the chest, they have one pairs of mammae.” Its unique characteristics are the grasping fingers aid in power grip that they have. They have opposite thumb and foot are plantigrade “(6).

Lets look at order Proboscidea. These animals have thick skin and it also have the little hairs. These are the animals such as elephant. Most of these animals have horns. Most of the animals found here are big.

Order Rodentia, all the animals that are found here are rodents. They are small animals. However these are the animals that have one pairs of chisel. Animals that are found under Rodentia order are squirrels, chimpmunk, rats, mice, voles, and beavers and bemmings. They have diastema between premolars and incisors.

Order Scandentia have small body size but they have long tails. Its eyes are facing forward and they have poorly developed claws. The animals belongs here are Typayas

In the order Sirenia,we found examples of animals such as Dugongs and Manatees. Most of these animals do not have teeth but they have flat tail.

Tubulidentata is one of the order of placental mammals. They have very thick skin. They also lack incisors and canines in adult. The teeth are also rootless. Animals that are found here are aardvark.

I n the order of placental mammals we found Xenarthra sometimes they called Edentata.They have long and sticky tongues. They also have long claws on the front feet and five toes on the hind feet. Animals that are found under this order are Sloths, Armadillos and true anteaters.

Afrosoricida is found in the order of placental mammals. Animals that are found here are goldens moles and terecs.

Just conclude Eutheria is the largest subclass of mammals. Each orders have different charecteristics and different animals. For examples, animals that are found under Insectivora eat only insects where as animals found in carnivores, are strickly meat eaters. It is easy for one to identify which animals belong to whch orders.

References

1. Moreillon,J. 2000-2005, Orders of Mammals in Sabino Canyon
[Online]. Available from: http://storytrail.com/SabinoCanyon/orders.html©

2. Wikipedia contributors.Eutheria [Internet]. Wikipedia, The free Encyclopedia, 22:55, 25 May 2006 UTC [Cited 29 May 2006 10:15] Available from: http://en.wikipedia.org/wiki/Eutheria

3.Wikipedia contributors. Mammal [Internet]. Wikipedia, the free Encyclopaedia, 00:51, 10 May 2006 UTC [Cited 12 May, 2006, 5:25] Available from http://en.wikipedia.org/wiki/Mammals

4. Murphy, W.J; Eiziric,E, E. 2001. Molecular dating and biogeography of the early placental mammal radiation. [Online]. Available from: http://jhered.oxfordjournals.org/cgi/content/full/92/2/212 [2006 May, 12]

5. Byers, R. 2005. Post-Flood Marsupial Migration Explained. [Online]. [Cited 12 May, 2006, 11:20]. Available from:http://www.rae.org/marsupials.html [19 October 2005, 12: 20]

6. Durham, N.H. Nature works mammals. [Online] [Cited 25 May, 2006 15:10]. Available from:http://www.nhptv.org/Natureworks/mammalia.htm

7. Murphy, W.J 2001. Molecular phylogenetics and the origins of placental mammals. [Online]. Available From:http://www.museums.org.za/bio/mammals/eutheria.htm

Linette Netshiheni
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