Placental Ruminants and Herbivorous Marsupials of Australia Essay

placental mammal Ruminants and Herbivorous Marsupials of AustraliaThe marsupial animal species that sacrifice evolved on the isolated unadulterated of Australia are unique compared to the rest of the animal solid ground in galore(postnominal) ways due to the harsh and distinctive environs found on the continent. The major area of marsupial biology that distinguishes them from either other placental mammals is their mode of reproduction. However, it heap be said that at that place are legion(predicate) other areas in which unique differences can be seen mingled with marsupials and eutherian mammals one much(prenominal) area of adaptation is in the course and physiology of digestion, which distinguishes them from legion(predicate) other similar animals worldwide. The foregut fermenters, such as kangaroos and wallabies, evolved in regions of poor provender quality to be able to extract the nigh nutritiouss out of the poorest feeds. excitement in the foregut has ma ny advantages over hindgut fermentation, which is seen in marsupials such as the koalas and wombats. The anatomy and physiology of the digestive tracts of some(prenominal) types of fermenters, however, are uniquely suited to their individual modes of nutrition. It can be suggested that the foregut fermenters of the marsupials are precise similar to the eutherian ruminants, as both types of adaptations are designed to increase fiber digestibleness and increase nutrient absorption. However, there are many major differences between the two groups. Ruminants have developed a four-chambered stomach system, which is non seen in the marsupials, as hygienic as a rumination cycle which allows for the rechewing of antecedently ingested meals. While vomit may be evident in marsupials, it is, however, not analogous to rumination, and is preferably called merycism.... .... 23 March 2004.Milewski, A.V. and R.E. Diamond. 2000. Why are very large herbivores transfer from Australia? A new theory of micronutrients. Journal of Biogeography. 27(4) 957-978. Russell, J.B. 1988. ecology of Rumen Microorganisms zip fastener Use. In Dobson, Alan, and Marjorie J. Dobson, eds. Aspects of Digestive Physiology in Ruminants Proceedings of a Satellite Symposium of the thirtieth International Congress of the International Union of physiologic Sciences. Cornell University Press Ithaca, NY, pg 74-98.Stevens, C.E. and I.D. Hume. 1995. relative Physiology of the Vertebrate Digestive System. Cambridge Cambridge University Press. Strahan, Ronald, ed. 1995. The mammals of Australia. Smithsonian Institution Press Washington, DC. train Soest, Peter J. 1994. nutritional ecology of the ruminant. Ithaca Comstock Publishing. Placental Ruminants and Herbivorous Marsupials of Australia EssayPlacental Ruminants and Herbivorous Marsupials of AustraliaThe marsupial animal species that have evolved on the isolated continent of Australia are unique compare d to the rest of the animal kingdom in many ways due to the harsh and distinctive environment found on the continent. The major area of marsupial biology that distinguishes them from all other eutherian mammals is their mode of reproduction. However, it can be said that there are many other areas in which unique differences can be seen between marsupials and eutherian mammals one such area of adaptation is in the anatomy and physiology of digestion, which distinguishes them from many other similar animals worldwide. The foregut fermenters, such as kangaroos and wallabies, evolved in regions of poor forage quality to be able to extract the most nutrients out of the poorest feeds. Fermentation in the foregut has many advantages over hindgut fermentation, which is seen in marsupials such as the koalas and wombats. The anatomy and physiology of the digestive tracts of both types of fermenters, however, are uniquely suited to their individual modes of nutrition. It can be suggested that the foregut fermenters of the marsupials are very similar to the eutherian ruminants, as both types of adaptations are designed to increase fiber digestibility and increase nutrient absorption. However, there are many major differences between the two groups. Ruminants have developed a four-chambered stomach system, which is not seen in the marsupials, as well as a rumination cycle which allows for the rechewing of previously ingested meals. While regurgitation may be evident in marsupials, it is, however, not analogous to rumination, and is instead called merycism.... .... 23 March 2004.Milewski, A.V. and R.E. Diamond. 2000. Why are very large herbivores absent from Australia? A new theory of micronutrients. Journal of Biogeography. 27(4) 957-978. Russell, J.B. 1988. Ecology of Rumen Microorganisms Energy Use. In Dobson, Alan, and Marjorie J. Dobson, eds. Aspects of Digestive Physiology in Ruminants Proceedings of a Satellite Symposium of the 30th International Congress of the International Union of Physiological Sciences. Cornell University Press Ithaca, NY, pg 74-98.Stevens, C.E. and I.D. Hume. 1995. Comparative Physiology of the Vertebrate Digestive System. Cambridge Cambridge University Press. Strahan, Ronald, ed. 1995. The mammals of Australia. Smithsonian Institution Press Washington, DC.Van Soest, Peter J. 1994. Nutritional ecology of the ruminant. Ithaca Comstock Publishing.