Homo sapiens means “wise person.” If the 4.5 billion year Earth history was compressed into a 24-hour clock, we would have arrived on the scene in the last 4 seconds! Yet we are making our presence known in Earth’s record in a big way.
The International Anthropocene Working Group is meeting in the Summer of 2016 to determine if a new geological epoch should be attributed to human activities. The impact that we have had to date is putting all of Earth’s biodiversity at risk of extinction.
It all started 60,000 to 80,000 years ago when humans began migrating North and East out of Africa. As they moved to new territory, they hunted the large animals for food and hides. One billion mega fauna such as Woolly Mammoths, Mastodons, Saber-toothed Cats, Giant Sloths, Dire Wolves, Giant Bison, Short-faced Bears, and Giant Beavers, were driven to extinction along the way.
The situation is worse today. Of the two million identified species, we actively monitor about 64,000, and of those, 25,000 (40%) are currently threatened with extinction. The threats are mainly human-caused and can be remembered with the acronym HIPPO.
H – Habitat Loss
There are over 7 billion humans on the planet and that number may be close to 12 billion by 2100. All those people need places to live and work, land for agriculture and pastures, fresh water, clean air, and places for waste. Consequently, we are changing the planet’s biosphere by converting rain forests to farms, depleting the world’s fisheries, changing the global temperature and air quality from fossil fuel usage, draining the aquifers, and filling in wetlands. Plants and animals are losing their niches and cannot move or evolve fast enough to adapt.
I – Invasive Species
With the development of inexpensive global transportation, imports and exports of plants and animals around the world has exploded. The United States used to be covered with beautiful, majestic Chestnut trees. It was the most numerous of the trees. Nursery plants imported from Japan to the East Coast in 1906 carried a blight that was new to the U.S. called Chestnut Blight. It got lose into the wild and by 1940 nearly all the American Chestnuts had been destroyed.
In the early 2000’s it was fashionable for some people in Florida to have imported Python snakes for pets. But as they grew to 23 feet and weighed 200 pounds they became too much for their owners who released some of them to the Everglades. There are now an estimated 150,000 of them in the Everglades and they are at the top of the food chain with no predators. They are wiping out all native animal species, including alligators.
P – Pollution
We figured out that it is easier to spray weeds with a chemical herbicide than to pull them out by hand. Consequently chemicals are sprayed on all of our food crops for weed and pest control and around our homes as well. Runoffs from our agricultural fields and home landscapes end up in rivers and eventually in gulfs and oceans. These toxic brews kill coral reefs (with a large proportion of marine life), wipe out fishing and crabbing grounds, and reduce the amount of fresh water available. In addition, chemically contaminated wetlands are killing off birds and amphibians.
P – Population
The ecosystem services provided by biodiversity (oxygen generation, climate regulation, soil creation, nutrient recycling, seed distribution, pollination, waste disposal, water purification and retention, flood and erosion control, timber production, and pharmaceutical and medical contributions) are being used up by the human population faster than they can be created. World Overshoot Day (the day humans use up a year’s worth of ecosystem services) occurred on August 14th in 2015. It was August 19th in 2014. This means we are using up the Earth faster than it can recover. This will become worse as the population increases and as the world standard of living increases.
O – Over-harvesting
The Blue Whale is the largest animal ever at 100 feet long and 200 tons weight. It was nearly hunted to extinction because of “Return on Investment.” From a business point of view it is more profitable to hunt a species to extinction and then invest the profits in a new enterprise than to harvest it sustainably indefinitely. The Blue Whale and other whales were saved from extinction by the 1966 treaty put together by the International Whaling Commission.
Recent animals in danger of becoming extinct due to over-harvesting include the Mountain Gorilla, Elephants, Rhinoceros’, Frogs, and Toads.
So today’s plants and animals not only have to deal with normal causes of extinction but have the additional threats of HIPPO causes from human activities. Here are the percentages of species at risk of extinction for several groups:
- Birds – 13%
- Fish – 21%
- Reptiles – 21%
- Mammals – 25%
- Invertebrates – 30%
- Corals – 33%
- Amphibians – 41%
- Plants – 68%
Imagine looking out of your window and 2/3’s of the tree and shrub and grass and grain species are missing! That could be the scenario for the next generation of Homo sapiens. How long do you think our species can last without a vibrant and bio-diverse ecosystem? The Anthropocene Epoch may very well be the last one recorded unless we change our ways.