“The ants are in turn dwarfed by the beetles. Erwin estimated that over 18,000 species occur in 1 hectare of Panamanian rain forest, with most previously unknown to science – in other words, still lacking a scientific name. To date, only 24,000 beetle species are known from all of the United States and Canada, 290,000 from the entire world.”
An increasing gradient in species richness is encountered while travelling from the poles to the equator. It was first described in 1807 by Alexander von Humboldt and has become one of the best documented broad-scale spatial patterns of life on earth. The gradient suggests that equatorial tropical regions are more species rich than temperate regions of the earth.
Tropical rainforests form an emerald belt around the globe, and though occupying only 6 percent of the earth’s land surface, are believed to contain more than half of the worlds living organisms. No exact estimates of species diversity have been made, either for the world or for rainforests, thus, this statistic rests upon educated guesses and logical extensions by the theoreticians of biology; yet this circumstantial evidence grows more persuasive with time and research efforts.
The world record for tree diversity at one site was set by Alwyn Gentry in the Amazonian rainforest near Iquitos, Peru. He found about 300 species in each of two 1-hectare plots. Peter Ashton discovered over 1,000 species in a combined census of ten selected hectare plots in Borneo. These numbers are to be compared with 700 native tree species found in all of the United States and Canada.
The emerald belt around our planet is currently being lost at a rate of 1.5 acres every second. It is estimated that over 100 species are lost every day, most unknown to science.
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