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More About Wild Species

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More About Wild Species

© Richard Grossman MD, 2008


The library of life is burning and we do not even know the titles of the books.

Dr. Gro Harlem Brundtland, former Prime Minister of Norway


            September’s article announced a contest to write about your favorite species of animal. It gave hints about my favorite animal, and promised to reveal what it is. Although the contest’s official deadline is past, I welcome submissions at:

            Why am fixated on wild species? Because they make up our most precious treasure, biodiversity. Biodiversity, or biological diversity, refers to the huge number of different plants and animals that have developed over the ages. Almost two million different species have been described and cataloged. Biologists suggest that the actual number of different species is many times this great. There may be another eight million animals and plants that haven’t been described yet!

            My friend, Al Schneider, just found a new species of plant in the sunflower family north of Cortez. Gutierrezia elegans has just been given its common name, Lone Mesa snakeweed. For more information and pictures of this pretty plant you can go to Al’s website: Just think, there may be many more undescribed species right where we live!

The tragedy is that we are losing biodiversity faster than species are being described. Our era is dominated by humans, and we are causing species to go extinct at an alarming rate. The last time that there was such a rapid loss of biodiversity was the end of the epoch of dinosaurs.

There are several ways humans cause species to die off. One is by direct killing, such as the dodo, a flightless bird that was hunted to extinction. Another is by introduction of exotic species. Australia had no proper mammals except for the dingo, (Canis lupus dingo, probably brought by the first aboriginal settlers) until Europeans arrived. They introduced foxes, rabbits and other domestic animals that out-competed and wiped out many of the more primative marsupials.

Pollution threatens many living things, including whole species. The bird with the largest wingspan in North America is an example. The California condor (Gymnogyps californianus) was headed toward extinction from lead poisoning. They would feed on carrion that had been shot with lead bullets. An aggressive program of limiting lead shot and hatching chicks in a laboratory has reestablished these amazing birds.

In most of the world, including the USA, the largest threat to biodiversity is habitat destruction. People in our country are living in larger homes on larger lots with larger lawns, competing with wildlife. Roads and highways block migration routes of many animals, thus creating killing zones for many who attempt to cross. As the human population grows and we consume more, our impact on the natural world is exploding.

Dr. E.O. Wilson, the famed Harvard biologist, made a superb video in which he pleads for preservation of biodiversity. Search for it at: Wilson uses the acronym HIPPO to help remember the causes of loss of biodiversity: Habitat destruction, Invasive species, Pollution, Population growth (human), and Overharvesting. There is also a beautiful book in the Durango Public Library titled Sustaining Life: how human health depends on biodiversity. This book shows the many ways we depend on species that we might not even be aware of.

The growing human population—and our extravagant consumption—are the primary factors that threaten biodiversity. The Living Planet Report 2008 tells it like it is. Prepared in part by the World Wildlife Fund, this is an account of the state of our natural world. It is available at: The report describes the economic value of biodiversity and the many services that the natural world performs for us. The report compares our use of resources with what is available.

Oh, yes; my favorite species is Hyles lineata, the white-lined sphinx moth. Like most sphinx (or hawk) moths, it has a wide body. It is usually seen in the evening or night, although I have seen them in broad daylight.

One of this species’ endearing qualities is its vision. H. lineata can discriminate colors when the light is very dim. Whereas humans need sunlight to see colors, and some animals perceive them even in dim moonlight, my favorite (other than H. sapiens) species can discriminate colors by faint starlight! Even on the darkest night these moths can find their favorite flowers to sip nectar.

There is amazing diversity in the natural world. Unless we slow our population growth and our consumption, we will leave scant resources for our progeny.


Published in the Durango Herald 11-2008

By Richard

I am a retired obstetrician-gynecologist who has been fortunate to live and work in the wonderful community of Durango, Colorado for 40 years.

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