Name: Kat Perlman—TA
Student ID#: 932673942
GEO 300 Fall 2015
CT#: 1-4
Q#: 1-10
Word Count: 526 (citations not included)
Extinction Rates and Ecosystem Changes are Accelerating in the Current “Anthropocene”
Interpretation (39 words):
The current era is widely scientifically labeled the “Anthropocene,” a period characterized by
widespread man-made environmental changes and prolific extinction rates (Corlett 2015, pg. 36). As
biotic communities shift irrevocably from historic structures, humans face potentially unsuitable global
environments and unknown futures (Kidwell 2015, pg. 4926).
Analysis (412 words):
Humans have influenced plant and animal populations and biotic community structures for centuries
(Caro et al. 2012, pg. 185; Corlett 2015, pg. 37), but current research indicates that present-day
anthropogenic impact is having greater effects on global ecosystems and environmental traits than
previously believed. Studies place current extinction rates from 100-1000 times greater than natural
levels, with the driving anthropogenic factors expected to persist far into the future (Zalasiewicz 2010,
pg. 2230). Paleobiological research indicates that, historically, “climate-driven reshuffling” of plants and
animals did not involve such drastic extinction numbers (Kidwell 2015, pg. 4925). Though much
attention is focused on the loss of “charismatic megafauna”—dodo birds and Tasmanian tigers, for
example—plants, invertebrates, and aquatic species are being lost just as rapidly. Present predictions
place the world’s fisheries at 32-57% overexploited, and shallow-water ecosystem “simplification” has
accelerated in recent decades. Marine mammal extinction rates have likewise been on the rise since the
onset of the Industrial Age (Kidwell 2015, pg. 4927).
Human activities are directly linked to changing ecological systems across the globe. With a current
population topping 7 billion and growing, human material input, resource extraction, and habitat
modification of the planet have skyrocketed (Zalasiewicz 2010, pg. 2229). Artificial chemicals increase in
both air and water systems yearly (Caro et al. 2012, pg. 185), and erosion and sedimentation have far
surpassed pre-human era measurements (Zalasiewicz 2010, pg. 2229). Wild animals are harvested
beyond recoverable limits, with insignificant decreases in hunting pressure (Kidwell 2015, pg. 4927).
These anthropogenic modifications to global environments are not only accelerating extinction rates
and plummeting biodiversity, but also dismantling behavioral and life history dynamics of many wild
species. Migrations, reproductive cycles, hunting grounds, and food web complexity are continually
threatened by human impact, likely compounding already elevated extinction patterns (Kidwell 2015,
pg. 4926; Zalasiewicz 2010, pg. 2229). Specific ecosystem services and functions will be lost as the
historic structures of global biotic communities are compromised to a disappearing biodiversity.
Modern environmental research and fossil record analysis shows that the changing environment—
including climate composition and ocean pH—is moving beyond the limits of what humans have
historically experienced (Corlett 2015, pg. 38). As evinced by the accelerating loss of species
composition worldwide, this changing environment spells trouble for the human race. Many scientists
agree that much of the global landscape has been altered irrevocably, but that preserving the remaining
“functioning” ecosystems is invaluable to survival in an unknown future (Corlett 2015, pg. 38).
Essentially all of the world’s biomes have to date been affected by human modification in some capacity
(Caro et al. 2012, pg. 185), making the “Anthropocene” a very relevant period of time to both scientists
and civilians alike. As human modification of the planet shows no signs of slowing, the current trend of
global restructuration and extinction trends indicate what the future holds for humanity.
Evaluation (34 words):
All cited literature is written by physical scientists, published in environmental journals. Social science
expertise lacks representation in this analysis, thus the predictions regarding humanity’s social approach
to the changing world may hold inaccuracies.
Inference (21 words):
Anthropocene extinctions and altered ecosystems may affect humanity’s ability to predict global
climatic events and adequately provide for a burgeoning population.
Explanation (20 words):
The current global era is characterized by human-caused ecosystem change and elevated extinction
rates, beyond what humans have previously experienced.
Literature Cited
Caro, T., Darwin, J., Forrester, T., Ledoux-Bloom, C., & Wells, C. (2012). Conservation in the
Anthropocene. Conservation Biology, 26 (1), 185-188.
Corlett, R.T. (2015). The Anthropocene concept in ecology and conservation. Trends In Ecology &
Evolution, 30 (1), 36-41.
Kidwell, S. M. (2015). Biology in the Anthropocene: Challenges and insights from young fossil records.
Proceedings of the National Academy of Sciences of the United States of America, 112 (16),
4922-4929.
Zalasiewicz, J., Williams, M., Steffen, W., & Crutzen, P. (2010). The New World of the Anthropocene.
Environmental Science & Technology, 44 (7), 2228-2231.