The Sixth Species Extinction Event by Humans

By Victor J. Nazarevich
Earth Common Journal
2015, Vol. 5 No. 1 | pg. 2/2 |

Extinctions in better known groups of vertebrates are at rates comparable to many mass extinctions in the geological past. There is evidence to suggest that contemporary extinctions have not been as high as predicted for a number of reasons. Some of the reasons that contemporary extinctions have not been as high as predicted include effective conservation efforts, species surviving in managed landscapes, and "extinction debt", a term that loosely means "future extinction of species due to events in the past". Extinction debt occurs due to time delays between the impacts on a species, such as the destruction of habitat, and the species' actual extinction or disappearance. Conservation is effective in delaying extinction because the policies it initiates can protect key environments and restore habitats and populations to their former status. There are also some species that are so versatile that they can survive in a world where climate has changed as well (Costello, 2013). The marine species are a great example of this phenomenon because of their ability to thrive in a variety of climates in different oceans and seas.

Yet while marine species may be able to adapt to distribution to climate change more easily than terrestrial species are able to, there are a number of problems that affect them as well. Induced acidification of oceans due to climate change, stratification, and deoxygenation are the sort of changes that have contributed to mass extinctions of marine species over the course of millions of years. It is for this reason that global environmental changes present greater risk of mass extinction because of anthropogenic influences on the natural world than recent human-mediated extinctions. One other reason for this concern is local threats, including habitat loss, hunting, and harvesting, are now contributing to the possibility of an anthropogenic mass extinction along with climate change (Costello, 2013).

Human populations have had a direct impact on Earth's biodiversity. Coupled with their unique use of land, this species of ape has changed more than three-quarters of the terrestrial biosphere into what have been called "anthropogenic biomes" or anthromes. This has occurred by replacing native ecosystems with agricultural croplands and settlements and by managing and disturbing remnant and recovering ecosystems that are located within these used lands. This form of direct anthropogenic transformation has caused unprecedented global changes in the Earth's biodiversity as native species struggle to survive and many are also ultimately driven to extinction locally and globally. Domestic and exotic species are rapidly becoming established as well (Ellis, 2012).

Coral reefs are also another example of an exotic species that is on the brink. Due to the ocean acidification from human emissions, many suffer bleaching, which ultimately kills off the coral and eventually the species of fish and other animals that depend on such organisms for survival. Coral reef fisheries also depend on these unique creatures in order to maintain a livelihood for tens of millions of people. Sadly, with devastating habitat degradation and unsustainable fishing there is severe depletion of stocks of reef fish occurring. Understanding how the social and economic factors of humans play a role in interacting with fishing and habitat degradation with respect to fish stocks is of vital concern if sustainability of the coral reefs is to be ensured as well (Brewer, 2013).

Discussion

From the sources analyzed, there appears to be a few general ideas that emerge about a possible sixth mass extinction by humans. Ninety-nine percent (99%) of all life that has ever existed on this planet has become extinct (Pievani, 2014). For a large portion of their history, humans have been dependent on the environment for plants, animals, and water supply (Foley, 2013). Human population density, which drives land use intensification, might be the best indicator of anthropogenic ecological change than land use or habitat loss (Ellis, 2012). Local population pressure and external markets, for instance, have had additive negative effects on vulnerable reef fish (Brewer, 2013).

Preservation will only be possible if humans work hard enough, though it is harder than parachuting species into cross-cutting assemblages of social interest and material praxis (McKee, 2014). In other words, preservation is possible if the human race pushes for it, while at the same time we cannot just expect to take animal and plant species from certain areas and just leave them in an area we design specifically for them. There is a number of impacts this study has, not just for biologists, but for every living person on Earth who is affected by biodiversity loss. More research should be done on specific species of flora and fauna that are not as documented as well as other animals.

Conclusion

As the human race progresses into the future, crucial decisions must be made regarding the fate of the Earth's biodiversity. Technology will have to cooperate with all of Earth's floral and faunal species. Every single economy will have to be remade to allow species to recover and thrive. There should be investigation into the status of unknown species as there is a lack of documentation and sightings for these species. There should also be consideration in maintaining and protecting Earth's ecosystems while living in harmony with the environment.


Acknowledgements

This research paper is made possible from many people who have supported me in my academic studies. I would like to thank my mother for always having faith in my abilities and my father for always giving me guidance when I needed it. I would also like to thank my older brother for his role as a peer reviewer and as a teacher who helped me improve my writing abilities. And finally, I would like to thank my younger brother for his peer reviewing and honest critique of the literature in this paper.


Author

Victor Nazarevich is a student in the Bachelor of Science (Physical Sciences, Earth and Planetary Sciences) degree program at MacEwan University.


References

Barnosky, A. D., Matzke, N., Tomiya, S., Wogan, G., Swartz, B., Quental, T., Marshall, C., McGuire, J. L., Lindsey, E. L., Maguire, K. C., Mersey, B., & Ferrer, E. A. (2011). Has the Earth's sixth mass extinction already arrived? Nature, 471, 51-57. DOI:10.1038/nature09678

Boyer, A. G. & Jetz, W. (2014). Extinctions and the loss of ecological function in island bird communities. Global Ecology and Biogeography, 23 (6), 679-688. DOI: 10.1111/geb.12147

Brewer, T. D., Cinner, J. E., Green, A., & Pressey, R. L. (2013). Effects of human population density and proximity to markets on coral reef fishes vulnerable to extinction by fishing. Conservation Biology, 27 (3), 443-452. DOI: 10.1111/j.1523-1739.2012.01963.x

Mora, C., Rollo, A. & Tittensor, D. P. (2013). Comment on "Can we name Earth's species before they go extinct?" Science 341, 237. DOI: 10.1126/science.1237254

Costello, M. J., May, R. M., & Stork, N. E. (2013). Can we name Earth's species before they go extinct? Science 25, 339 (6118), 413-416. DOI: 10.1126/science.1230318

Dirzo, R., Young, H. S., Galetti, M., Ceballos, G., Isaac, N., & Collen, B. (2014). Defaunation in the Anthropocene. Science 25, 345 (6195), 401-406. DOI: 10.1126/science.125181

Ellis, E. C., Antill, E. C., & Kreft, H. (2012). All is not loss: Plant biodiversity in the Anthropocene. PLoS ONE, 7 (1), 1. DOI: 10.1371/journal.pone.0030535

Figure 1. Effect of Fragmentation of Species Number. Adapted from "Species-area relationships and extinctions caused by habitat loss and fragmentation," by Ilkka Hanski, Joel Rybicki & Brian Enquist, 2013, Ecology Letters, 16 (Supplements 1), p. 29. Copyright 2013 by the National Academy of Sciences of the United States of America. Adapted with permission.

Figure 2. Effect of habitat fragmentation on the number of tropical bird species. Adapted from "Species-area relationships and extinctions caused by habitat loss and fragmentation," by Ilkka Hanski, Joel Rybicki & Brian Enquist, 2013, Ecology Letters, 16 (Supplements 1), p. 29. Copyright 2013 by the National Academy of Sciences of the United States of America. Adapted with permission.

Figure 3. Relationship between extinction rates and the time interval over which the rates were calculated, for mammals. Adapted from "Has the Earth's sixth mass extinction already arrived?" by Anthony D. Barnosky, Nicholas Matzke, Susumu Tomiya, Guinevere O. U. Wogan, Brian Swartz, Tiago B. Quental, Charles Marshall, Jenny L. McGuire, Emily L. Lindsey, Kaitlin C. Maguire, Ben Mersey & Elizabeth A. Ferrer, 2011, Nature, 471, p. 51-57. Copyright 2011 by Nature Publishing Group, a division of Macmillan Publishers Limited. Adapted with permission.

Foley, S. F., Gronenborn, D., Andreae, M. O., Kadereit, J. W., Esper, J., Scholz, D., Pöschl, U., Jacob, D. E., Schöne, B. R., Schreg, R., Vött, A., Jordan, D., Lelieveld, J., Weller, C. G., Alt, K. W., Gaudzinski-Windheuser, S., Bruhn, K., Tost, H., Sirocko, F., & Crutzen, P. J. (2013). The Palaeoanthropocene – The beginnings of anthropogenic environmental change. Anthropocene, 3, 83-88. DOI: 10.1016/j.ancene.2013.11.002

Pievani, T. (2014). The sixth mass extinction: Anthropocene and the human impact on biodiversity. Anthropocene – Natural and Man-made Alterations of the Earth, 25, (1), 85-93. DOI: 10.1007/s12210-013-0258-9

Sodikoff, G. M. (2012). The anthropology of extinction: essays on culture and species death (Title not in italics). Genese Marie Sodikoff, (Ed.). Bloomington: Indiana University Press

Rybicki, J., Hanski, I., & Enquist, B. (2013). Species-area relationships and extinctions caused by habitat loss and fragmentation. Ecology Letters, 16 (Supplements 1), 27-38. DOI: 10.1111/ele.12065

Suggested Reading from Inquiries Journal

In today's globalized world, international cooperation and information sharing becomes increasingly important. This paper examines the criteria provided in the United State's Endangered Species Act, the European Union's Habitat Directive, and the International Union for Conservation of Nature's Red List. The interplay between these... MORE»
Advertisement
Overcoming the threats of the snow leopard with immediate action may be what will save this species from extinction. This report provides a brief overview both of the challenges faced by the snow leopard and the roles local people have taken in the decline and subsequent recovery of this apex predator. Panthera uncia... MORE»
The terrestrial Mojave Shoulderband Snail (Helminthoglypta (Coyote) greggi) is being considered for status and protection as an endangered species under the Endangered Species Act due to the recent construction... MORE»
MacGillivray Freeman Films was founded over forty years ago by Greg MacGillivray and the late Jim Freeman. In 2011, the company launched “the world’s largest ocean media campaign, a 10-year global initiative called One World One Ocean” (MacGillivray Freeman Films, 2010, Our History, para. 10), an awareness and... MORE»
Submit to Inquiries Journal, Get a Decision in 10-Days

Inquiries Journal provides undergraduate and graduate students around the world a platform for the wide dissemination of academic work over a range of core disciplines.

Representing the work of students from hundreds of institutions around the globe, Inquiries Journal's large database of academic articles is completely free. Learn more | Blog | Submit

Follow SP

Latest in Environmental Studies

2017, Vol. 9 No. 05
Is it possible to objectively define the Anthropocene? This essay argues that whether or not it is precisely definable as a geological epoch, its true value, as a concept grounded in futurity, lies within the social realm. The origins of the term... Read Article »
2013, Vol. 3 No. 1
Published by Clocks and Clouds
Postmaterialist values, those that emphasize higher-order human needs, have become widely accepted as the determining force behind environmentalism in the West. Little research has been dedicated to studying the importance of these values outside... Read Article »
2017, Vol. 9 No. 03
In Gallup’s 2016 environment poll, 64 percent of U.S. adults are now worried a “great deal” or “fair amount” about global warming, with a record 65 percent attributing warming primarily to human activities (1). These... Read Article »
2016, Vol. 6 No. 1
Despite all the information we have regarding climate change and the potential perils of continuing on our path of consumption, people are slow to make the necessary changes. Our tendency to live habitually and the dampening effect continuous negative... Read Article »
2016, Vol. 6 No. 1
Whenever a decision is made in a social, political, or economic context, it is implicitly grounded in an ethical outlook. But where do these outlooks come from? To investigate this query, I examine the basis for ethical decisions regarding technology... Read Article »
2016, Vol. 6 No. 1
In today's globalized world, international cooperation and information sharing becomes increasingly important. This paper examines the criteria provided in the United State's Endangered Species Act, the European Union's Habitat Directive, and the... Read Article »
2016, Vol. 6 No. 1
Climate change and the myriad of challenges that come with it are a reality the entire world must face. However, for Canadian province, Alberta, the stakes are especially high. Oil and gas mining made up 18.3% of Alberta's GDP in 2015 and therefore... Read Article »

What are you looking for?

FROM OUR BLOG

"Should I Go to Graduate School?"
How to Read for Grad School
Finding Balance in Graduate School