Edited sentence: If this rate of extinction continues or accelerates, the number of species becoming extinct in the next decade could number in the millions.The high rate at which species have become extinct within the last 150 years is a cause of concern.The risk of species extinctions at present is estimated at 100 to 1000 times "background" or average extinction rates in the evolutionary time scale of planet Earth; moreover, this current rate of extinction is thus 10 to 100 times greater than any of the prior mass extinction events in the history of the Earth.While most people readily relate to endangerment of large mammals or birdlife, some of the greatest ecological issues are if key species vanish at any level of the food chain.While species have evolved and become extinct on a regular basis for the last several hundred million years, recent rates of extinction are many times higher than the typical