The affect of temperature as an environmental pressure that affects mammalian life.
Write 3 pages thesis on the topic the affect of temperature as an environmental pressure that affects mammalian life. The Effect of Temperature on Mammalian Life  . .  . The Effect of Temperature on Mammalian Life Introduction Mammalian animals are members of the vertebrate group characterized by endothermy, mammary glands, hair, sweat glands and middle ear bones. These animals are known to regulate their body temperature, which is a significant factor influencing their life and physiologic processes. Temperature, which denotes the intensity of heat possessed by an object or substance, is often a significant element of climate. As such, it is one of the abiotic factors, which influence ecosystems and their flora and fauna. All plant and animal life is adapted to survive within a certain range of temperature. The earth has various regions zoned according to temperature, and these zones are inhabited by different types of animals and plants depending on how well they are able to tolerate the temperature in these zones. Mammals are homeothermal in nature and they are able to control their temperature so as to retain it within their natural range. If the regulatory system fails due to excessive increase of decrease, then, these animals often die. In essence, temperature acts as a significant factor that influences many aspects of mammalian life. Its pressure on mammalian ecosystems and physiology has been a significant shaping force of mammalian evolution, geographic distribution and overall survival. This paper highlights various research studies that have helped in supporting this thesis by proving the effect of temperature on mammalian microevolution, habitat distribution and overall physiologic processes such as growth. Perhaps the first and most significant influence of temperature on mammalian life is growth rate. A research by Kaufmann et al (2000), found that mammalian cell proliferation can be controlled by changing cell cultivation temperatures. The research revealed that the shifts in temperature affects protein formation, especially. at the translation stage of protein expression. A decline in culture temperature from 37°C to 30°C in the research caused arrested growth of Chinese hamster ovary (CHO). Additionally, observed proteome changes showed that mammalian cell response to cold temperature also entails changes in protein modifications at the post-translational stage. The findings of this study are supported by other similar study by Watanabe and Okada (1967), which showed that temperature significantly, influences the rate of growth of mammalian cells. These studies show that temperature influences the rate of growth among mammals. The above studies are further supported by the duo of Maria and Slade (1999), who proved that seasonal weather changes, which include temperature significantly affected the growth rates and weight of mammalian Cotton Rats (Sigmodon hispidus). These studies prove that temperature is a significant physiologic influence in mammalian growth and development. The fact that temperature has such an effect on mammalian life implies that it must have also been a significant influence the mammalian evolutionary process. Interestingly, studies on microevolution have revealed that the DNA of mammals living in warmer climatic zones changes at a rate that is faster than that of mammals residing in cooler climates (Weir & Dolph, 2011. Husby et al, 2011). These studies have partially explained why the tropics are species-rich, and also proven the fact that temperature has influence on mammalian microevolution. The microevolution processes create beneficial changes such as resistance to diseases and heat, but never lead to the development of new species. A study by Weir and Dolph (2011), affirms that mammalian molecular evolution is influenced by temperature, but it disputes the rate at which this occurs by assessing a previous study by Gillman and others. The reveals that there is some acceleration of molecular evolution among mammals, which is attributable to warmer environments. A similar study by Husby et al. (2011) showed that microevolution among wild birds is speedier in regions with warmer temperature than others, and thus proving that temperature is indeed a significant determinant factor in the microevolution process. The fact that temperature has some influence on evolution implies that it may also affect habitation and distribution of mammals within various ecosystems. Cameron and Scheel (2001), state that distribution of plants and animals is significantly influenced by changes in global and regional temperatures. The study by Cameron and Scheel (2001) proved that rodent distribution in the Texas was significantly influenced by temperature levels and zones. This study supports other earlier studies such as that conducted by Rice (1923) in Alabama. These studies show that the distribution of various types of mammals is influenced by regional temperature, which determines the suitability of an area as a habit. Conclusion In conclusion, temperature is a significant factor in determining mammalian life sustenance and development because it could negatively or positively impact mammalian life through affecting growth and evolutionary processes. Mammals are homeothermal animals and they regulate their temperature to fit bodily requirements. As such, they cannot survive well in environments with extremely low or high temperatures because these environments strain the mammal’s ability to regulate and maintain body temperature within normal limits. As such, mammals often move into environments with ambient temperatures. Therefore, temperature affect habitat selection, growth and evolution of mammals-all of which are significant influences on mammalian life. References Cameron, N. D. & Scheel, D. (2003). Getting Warmer: Effect of global climate change on distribution of rodents in Texas. Journal of Mammalogy, 82 (3), 652-680 Husby, A. Marcel, E. V. & Loeske, E. B. K. (2011). Speeding up Microevolution: The Effects of Increasing Temperature on Selection and Genetic Variance in a Wild Bird Population. PLoS Biology, 9(2): e1000585, 1-9 Kaufmann, H. Xenia, M. Martin, F. & James, E.B. (1990). Influence of low temperature on productivity, proteome and protein phosphorylation of CHO cells. Journal of Biotechnology and Bioengineering, 63 (5), 573-582 Maria. A. E. & Norman, A. S. (1999). Effect of Weather on Individual Growth Rates in Cotton Rats, Sigmodon hispidus. Journal of Mammalogy, 80 (4), 1277-1287. Rice, R. L. (1923). Life Zones and Mammalian Distribution. Journal of Mammalogy, 4(17), 39-47. Watanabe, I. & Okada, S. (1967).Effect of Temperature on Growth Rate of Mammalian Cultured Cells (L5178Y). Journal of Cell Biology, 32(2), 309–323. Weir, T. J. & Dolph, S. (2011).Are rates of molecular evolution in mammals substantially accelerated in warmer environments? Proceedings of the Royal Society, 278(1710), 1291–1293.