Biology Enhanced, Kits
Due Wednesday, May 6, 2015
Mammals are the most advanced of all animals by the way their body works.
Their digestive system, respiratory system, and circulatory system are much more complex than other animals in the animal kingdom.
One way the Mammals exhibit their exceptionally developed body structure is comparing their feeding and digestive systems to those of other animals. One of the simplest phylums of animals, the Porifera, hardly have any system at all. The animals like sponges depend on diffusion, and are called filter feeders. Their cells engulf microscopic food particles that move through the sponge and then use them for nutrition. Birds have a much more advanced feeding system than sponges, however it is not as advanced as a mammals. Each species of bird has its own specialized beak fitted for their preferred environment. However they have no teeth so the food that they eat goes down into their crop where it is moistened, and then sent to their gizzard to be ground up. Mammals, in their broad range of diversity, have much more interesting and different ways of feeding and digesting food. Some animals such as carnivores, have specialized teeth, like canines, and claws that allow them to kill their prey with ease, and their digestive tracts are able to handle the all meat diet. Then there are other animals that are herbivores that have flat teeth that are suited to chewing grasses and grains.
Their digestive tracts are able to handle an all plant diet because they contain an
enzyme that is able to break down the plant fibers. These advanced feeding systems in comparison to the simpler systems of nonmammals allow mammals to thrive more so than their nonmammal coinhabitants.
Like their feeding systems, mammals also have a much more advanced respiratory system that those of other animals. For example the phylum of Cnidaria have no specialized system for their respiratory needs. They rely on diffusion to get the oxygen that they need in order to survive. Fish use fine filaments with capillaries, called gills, to get the oxygen that they need. Most pull the water through their mouths or their gill slits and then extract the oxygen from it. There are aquatic animals, however, that do not use gills, instead they have just developed their respiratory system in such a way that they are able to hold their breath underwater for extensive periods of time. An example of these are whales. Whales’ lungs work like human lungs, but humans can usually only absorbs about 15% of the oxygen they breathe in. Whales however can absorb up to 90%. Whales are able to store this extra