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Habitat Reduction and Loss of Bio-Diversity
Species extinction is a progressive process whereby certain types of animals become non-existent. It is caused by several factors, broadly categorized into natural and human causes (Angermeier, 2014). The non-existence of any species in the ecosystem causes a lot of detrimental effects to other species who either directly or indirectly depend on them. The effects also impact directly on the existence of human beings wholesomely as it impacts on their health, their environment and climate.
One of the natural causes of extinction is current or sea level changes whereby any ocean floor rise leads to significant displacement of water to the land that already has existing settlements. Additionally, volcanic gases when absorbed by these waters leads to unsuitable changes to the chemical composition which makes it uncomfortable for some species’ life (Clavero & Garc, 2015). Another cause of extinction is the climatic change since not all species of animals are able to withstand the adverse climatic changes caused by the global warming.
Cosmic or Asteroids Radiation is yet another renowned cause, whereby asteroids usually hit the earth surface with excess force and the side that experiences its impact becomes completely destroyed thus, extinction of affected species. On the other hand, cosmic radiation emitted from the sun and too much exposure to cosmic radiation causes gene mutation that can significantly weaken future gene pool of a species (Clavero & Garc, 2015). Besides the above causes, diseases or Epidemic also cause natural extinction; all species have unique immunity systems and defense mechanisms which they are rapidly losing due to landscape and climatic changes. Such changes make them susceptible to epidemics and diseases that can probably lead to their extinction.
Human causes of extinction are factors increased human population which leads to limited resources for the population and humans have to go an extra mile to devise survival ways such as hunting certain species that threatens their eventual extinction. Secondly, Destruction of habitat whereby people have displaced certain species through activities like agriculture and deforestation threatening the existence of affected species ((Pimm & Raven, 2010). Moreover, global warming also causes the undesirable climatic changes caused by human activities such as deforestation can possibly cause species extinction radiation.
Impact of species extinction on the ecosystem
Any species extinction can have potential consequences on the ecosystem, climate and the physical environment. Such consequences, especially when the conditions are extreme to support life such as direct extreme sunlight can lead to more extinction, a condition commonly known as keystone species meaning; a species that has broad effect on its surrounding in line with its total biomass and numbers. Such examples include the sea stars species that prey on mussels, and other shellfish. They typically lack other predators apart from these sea stars. Absence of these sea stars makes their numbers to explode thus out-competing other ecosystem species. Other examples include such animals like jaguar and grizzly bear that efficiently balance a whole ecosystem by assisting in the needed transfer of nutrients throughout the ecosystem due to their unique varied diet (Ehrlich & Mooney, 2013).
Members of this species are preferably called ecosystem engineers typically for their ability to transfer large amount of nutrients from the ocean to the land because of their ability to do salmon fishing during the season of spawning. Extinction of such engineers or any decline in their numbers translates into extreme effects on their surroundings. That is, all the life types that have lived to benefit from the actions of the engineers would also start to decline and eventually extinct. Extinction of certain species, particularly plants results in significant environmental changes. Such extinction can turn previous biologically productive land into wasteland. That is, the existence of such plants supports the lives of living soil micro organisms which automatically cease to exist with the plants’ death leading to infertility of the soil hence, waste land results.
Impact of ecosystem extinction on human health
Notably, the extinction of certain species leads to largely felt changes in the environment, local and even global climate that can highly affect human health. For instance, deforestation leads to extinction of certain medicinal plant species and the absence of such plants can negatively impact on the people who totally relied on them for their healing. Lack of trees and soil erosion causes increased flooding which is detrimental to human health. Floods cause unanticipated displacement, loss of lives and bring in water borne diseases that pose great threat on human lives (Daszak, Cunningham & Hyatt, 2010).
Extinction of species linked to sufficient water supply causes water shortage. As it is globally believed, water is life and without it, life might prove unbearable for we need water for almost all human activities and even for our daily consumption to help with bodily processes. Extinction of certain species would also translate into food shortages brought about by barren lands and fishless water bodies. Without proper food supply, human health becomes compromised and resultant disease and other undesirable health conditions would set in possibly causing death. Human beings have full dominion over all creation and they need the input of almost every living creature for comfortable living.
Loss of diversity due to extinction of certain species results in ill health of humans since some of these species exist to protect our health in one way or the other (Brook, Sodhi, & Bradshaw, 2013). For instance, trees provide healthy shade and protection from heavy winds, direct sunlight due to lack of shade might bring heat rush and too much perspiration that negates human health. Extinction of some species, particularly trees and plants leads to rising temperatures that might go too high threatening the lives of people. Such temperatures are also associated with some disease conditions such as heat rush that poses danger on human health. Pollution caused by such activities as deforestation can pose great danger on human health due to its unbearable effects like onset of diseases brought by pollution existence.
In conclusion, biodiversity is very important and should be highly maintained to avoid its negative impacts on human health and on the ecosystem. Moreover conservation of species life has a lot of benefits to dependent species as well as in maintaining desirable climate and environmental conditions.