Over the world’s history, scientists know of five mass extinctions that wiped out at least 75% of the world’s living species. Many new studies published in the journal of Science suggest that we are in the midst of another mass extinction. Human population continues to grow, and a destruction of habitats and global warming has proven detrimental to other species. Scientist predict that extinctions rates in the 20th century were 100 times faster than if humans were not inhabiting earth.
One study shows that the human population has doubled over the past 35 years, but in the same time the invertebrate animal population has declined by 45%. These invertebrates do not attract the same attention that large animals might. However, they are crucial to ecosystems functioning correctly. Lead author Rodolfo Dirzo of Stanford University states, “We tend to think of extinction as a loss of a species from the face of the earth, and that’s very important, but there’s a loss of critical ecosystem functioning in which animals play a central role that we need to pay attention to as well.” According to the study, 322 species have gone extinct over the past 500 years. So what is to come?
Another study lead by Anthony Barnosky of the university of California, berkeley found that three quarters of today’s animal species could vanish in the next 300 years. Additionally, Barnosky team found that over the past 65 million years, there has been an extinction rate of about two mammal species per million years. However, over the past 500 years a minimum of 80 mammal species have gone extinct. This is well above the average and suggests that we are in the beginning of another mass extinction.
Moreover, if all of the endangered mammal species go extinct within the next 100 years, in 334 years 75% of all mammal species will be gone. Barnosky team extended to the study to many other living organisms such as reptiles and amphibians and found that a similar trend is taking place. The team estimates that extinction rates are 3 to 80 times faster than what is considered normal.
The next logical question that someone may have is, will humans survive the sixth mass extinction? The answer to this question is not fully known. On one side, humans have proven that we are able to survive a loss of many species on earth. We are providing this right now. But what is the threshold? Is there a point when ecosystems are so dysfunctional that we can not accumulate sufficient amounts of food to feed our ever growing population. Moreover, the pollution that is killing off many species around us could one day become so severe it causes great health concerns in humans. In countries like China, the health effects of high pollution are already evident. Another question is, even if we can survive a drastic decrease in other species, is that the kind of world we want future generations to live in?
But is it too late to stop? The good and bad thing about this apparent sixth mass extinction is that we as humans have caused it. Due to increased awareness and technology, humans are able to delay the extinction of endangered species by placing them in controlled safe habitats. Additionally, many scientist believe, if we can return some species back to their original habitats, we may be able to slow the extinction rates. Additionally, if we are able to stop some of the obvious causes of global warming and habitat destruction such as pollution and rapid human population growth, we will be able to combat this increased rate of extinction.
Thus, it is evident that we are in at the beginning of another mass extinction like the one the dinosaurs faced millions of years ago. However in this situation, we are not the dinosaur’s, rather we are the asteroid. Stopping this human caused mass extinction will require a concerted effort from all of mankind.
Souces
http://news.stanford.edu/pr/2014/pr-sixth-mass-extinction-072414.html
http://time.com/3035872/sixth-great-extinction/
http://www.biologicaldiversity.org/programs/biodiversity/elements_of_biodiversity/extinction_crisis/
http://www.theweathernetwork.com/us/news/articles/climate-and-environment/what-up-in-climate-change-this-time-we-are-the-asteroid/55506/