Natural Selection Image Map

Animal Destruction of the Environment - Example

When Charles Darwin first encountered Galapagos Island, it was like a Garden of Eden, full of lush vegetation and a huge range of animal and plant species. Each species had specific physical features that made it capable of  operating within its specific niche.  For example, birds that cracked nuts for food had large, tough jaws and beaks. Birds that ate other kinds of food had beaks that were specialized for that kind of food.                                                                             






Satellite view of one of the Galapagos Islands, located 1200 kilometers West of Ecuador. This island has six active volcanoes. Craters of two are seen in this photo. Courtesy of NASA.

A few goats had been set loose by sailors in the hope that their offspring would provide food for ship personnel in the future. Today, goats have taken over the islands. Some of the islands are now stripped of vegetation. Before the arrival of goats, the islands had no plant-eating mammals except  turtles and iguanas that had low metabolism and ate little. Where goats have stripped everything, turtles and iguanas now face extinction. The don't eat much, but some vegetation is still essential for their survival. Turtles are also under attack from other human-introduced creatures: rats, dogs, and pigs dig up turtle eggs to eat. Iguanas are eaten by dogs and pigs.

How sad it is to see this devastation of this living museum of evolution.

Humans Are the Big Environmental Problem

We humans like to think of ourselves as superior to other species. We can do things with our brains that no other species can. This attitude of superiority has been called "speciesism." 

By what standards do we measure the superiority of a species?

  • Do we mean the ability create powerful tools and procedures that can even change the ecological niche in which a species lives? 

    By that measure, humans are clearly superior to all species.
  •  Do we mean the total number of similar species?

The fossil record has revealed no more than about a half-dozen human-like species.  All have become extinct, except one (our species). Meanwhile, bacteria and insect species number in the millions and have thrived for millions of years.

  • Do we mean the fitness to adapt to Nature's niches and thrive as a species?

    By that measure, humans fail to impress. Humans kill each other by the millions -- in war and with diseases, such as AIDs. The modern human species may be no more than 1/2 million years old, while bacterial fossils have been found that are 3.5 billion years old.

Humans are not immune to extinction. As the earth's population grows to the point where we have exhausted our resources or become so overcrowded as to encourage devastating plagues or wars, extinction becomes possible. More certain is that bacteria and bugs will be around long after we are gone. 

We humans dominate the earth and the other living things in it. We exploit Nature to satisfy our desires. We whitewash our excessive desires by defining them as rights. We selfishly decide that our rights come first ahead of those of other species that have no rights.  This viewpoint is then used to justify our abuse of the environment and the damage that we do to other species. 

Have you heard of "rogue elephants," which are elephants that run amok, causing devastation everywhere they go? Author John Livingston has called humans the "Rogue Primate." Is that what we have become?


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