1Within the last 50 years wildlife populations have declined, on average, by 60%. Planet Earth once had an abundance of species, but due to the destructive nature of humans, this abundance has reduced immensely.
Biodiversity is the variety of life on Earth, this includes the genetic diversity between individuals of one species as well as individuals between different species. Biodiversity can arise from a variety of ways, ranging from a genetic level to which ecosystem the organism lives in.
Individuals within a species show natural variation in their characteristics. This has developed from a genetic level from phenomena such as crossing over and mutations (only some examples). Crossing over is a stage in meiosis where the genes between non- sister chromatids get exchanged. This leads to, inevitably, organisms having different genotypes and as a result different phenotypes (physical appearances) from their parents.
Mutations are permanent changes in the DNA of an organism. These can be both random and influenced from the environment. For example, in an environment where there are high levels of radiation, mutation is more likely. Mutations can, again, change an organism’s phenotype and genotype. For instance, a mutation in the gene of a starfish can occur which may change its colour from pink to purple. This has now made it relatively different from other individuals of its species. This mutation may pass onto its offspring, so now they will all be purple.
These two scenarios are examples of how biodiversity can emerge within a community.
Recently, humans have had more of a negative impact on the biodiversity in some ecosystems. This has come from deforestation, burning of fossil fuels, drilling etc. All of these processes have and will fuel the rate at which climate change is happening. Whilst the devastating effects of climate change are now, more than ever, visible, the other indirect effects are less apparent. One of the effects is the destruction of habitats which is reducing biodiversity.
2Not long ago, a cargo ship ran aground on a coral reef in Mauritius. The coral reefs in Mauritius is what makes it a very popular holiday destination to tourists. But as well as tourists, the coral reefs are admired by a variety of species of marine animals. Undoubtedly, the oil spill has had its effects, environmentally, economically and socially. 3The situation was defined as an environmental emergency.
Since oil is hydrophobic and water is hydrophilic, they do not mix. Therefore, when oil spillages occur, the oil can be very evidently seen in the water. 4Bird’s feathers are water repellent and oil can decrease the repellency which makes them feel cold and they are now likely to suffer and die from hypothermia. 5Oil sheen can reduce the oxygen concentration in the water, which will directly impact the fish, as they will suffocate from the reduced aerobic respiration that they can carry out. In addition, oil spillage will block out some sunlight which is required for photosynthesis. As a consequence of this, the marine plants will no longer be able to grow and will soon die.
3The added catastrophe of this spill, was that an estimated 1000 tonnes of oil had leaked in one area, so the concentration of oil was very high.
Although the event was an accident, the after effects are nonetheless still disastrous.
As a result of the growing human population, it comes without question that its demands for food and land will also be increasing. 6The Amazon rainforest has been subject to felling in order to make space for cropland. The felling and the recent drier seasons has made forest fires more common. The fires have not only cleared some of the forest, but also has destroyed the habitats of many other animals, threatening them to extinction. This has reduced the biodiversity of our planet.
Although the economic and social impacts of Covid-19 were clearly negative, the environmental effects were not quite so. With cleaner waters, less air pollution and empty roads the wildlife had soon, fortunately, returned.
Small changes to our lifestyle, such as walking instead of taking a car, can make a big difference in terms of maintaining the biodiversity on Earth and preventing animals from becoming extinct.
- “Our Planet” documentary Last used on 1st September 2020
- Mauritius oil spill “https://www.nature.com/articles/d41586-020-02446-7” Last used on 1st September 2020
- Mauritius oil spill “https://www.bbc.co.uk/news/world-africa-53959889” Last used on 1st September 2020
- Effect on marine life “https://oceanservice.noaa.gov/facts/oilimpacts.html” Last used on 1st September 2020
- Effect on marine life “https://www.sciencemag.org/news/2010/05/oil-and-dead-zone#:~:text=The%20oil’s%20sheen%20could%20prevent,deeper%20waters%20are%20already%20stratified.&text=Oil%20reflects%20light%2C%20which%20is,also%20diminish%20the%20phytoplankton%20blooms.” Last used on 1st September 2020
- Felling of Amazon rainforest “https://www.bbc.co.uk/news/world-latin-america-53893161” Last used on 1st September 2020