May 01, 2012 · essay on Environmental Protection ..
contribute in protecting the environment
As the war continued, the Athenian hinterland was turned into a desert. Plato described the deforestation of , which remained barren until my lifetime, when the Greek government began to reforest it; many trees could only be planted by blasting holes in the limestone bedrock. When Attica's residents returned home after the Spartan occupation, they built their homes with a southern orientation to take advantage of sunlight, as wood was scarce. After five years of peace with Sparta subsequent to , Athens took to the offensive again and pretended to intervene in a war in Sicily to protect Ionian colonists, but they really did it to conquer Sicily and plunder its forests and other resources, and thereby build another naval fleet to conquer Sparta. The was a catastrophe for Athens, and it lost most of its navy. There were other setbacks and victories, but a starving and besieged Athens finally surrendered to the Spartans in 404 BCE. The environment around Athens could feed nothing but “bees,” and where wolves once abounded, not a rabbit could be found. As Athens slowly became the center of a wasteland, the changing perceptions could be seen in contemporary writing. When forests were plentiful in 700 BCE, Greek authors wrote of trees in pragmatic fashion or as impediments to progress. As the forests disappeared along with the ecosystems they supported, an ecological consciousness began to appear. Plato and Aristotle placed forests at the root of a civilization’s health, and . Conservation only became an idea when the environment had already been ruined by “progress." Numerous commentators of the day wrote about the connections between forests and a healthy water supply, and many clearly saw the relationship between deforestation, erosion, and desertification, including Plato. and his professional heir wrote about ecological ideas. Theophrastus could be considered the first ecological writer, and he had the beginnings of an ecosystems approach. He noted that when the region surrounding was deforested, it became dryer and warmer.
Short essay for students on environment conservation
So far in this essay, mammals have received scant attention, but the mammals’ development before the Cenozoic is important for understanding their rise to dominance. The , called , first , about 260 mya, and they had key mammalian characteristics. Their jaws and teeth were markedly different from those of other reptiles; their teeth were specialized for more thorough chewing, which extracts more energy from food, and that was likely a key aspect of success more than 100 million years later. Cynodonts also developed a secondary palate so that they could chew and breathe at the same time, which was more energy efficient. Cynodonts eventually ceased the reptilian practice of continually growing and shedding teeth, and their specialized and precisely fitted teeth rarely changed. Mammals replace their teeth a . Along with tooth changes, jawbones changed roles. Fewer and stronger bones anchored the jaw, which allowed for stronger jaw musculature and led to the mammalian (clench your teeth and you can feel your masseter muscle). Bones previously anchoring the jaw were no longer needed and . The jaw’s rearrangement led to the most auspicious proto-mammalian development: . Mammals had relatively large brains from the very beginning and it was probably initially . Mammals are the only animals with a , which eventually led to human intelligence. As dinosaurian dominance drove mammals to the margins, where they lived underground and emerged to feed at night, mammals needed improved senses to survive, and auditory and olfactory senses heightened, as did the mammalian sense of touch. Increased processing of stimuli required a larger brain, and . In humans, only livers use more energy than brains. Cynodonts also had , which suggest that they were warm-blooded. Soon after the Permian extinction, a cynodont appeared that may have ; it was another respiratory innovation that served it well in those low-oxygen times, functioning like pump gills in aquatic environments.