Show animal and plant species estimated to total about one and hilf half million the total number of species of plants and animals known to exist is conservatively estimated at 1 million according to a study of organic diversity issued issue dby by the columbia university press many new species are described every year and large additions may be expected in the future it Is pointed out while the true extent of organic diversity can only be surmised at present there are known species of animals the number of described species of flowering do plants is around and of lower plants these totals fall short of the actually existing number of species and do not take into account the variation which is commensurate only with the number of living individuals it is explained for centuries man has been interested te in ili the diversity of living beings says dobzhansky professor of genetics in california institute of technology author ofte study the multitude of the distinct kinds or species or organisms Is seemingly endless and within asp a species ecles no uniformity prevails in the case of man mail himself it is generally taken for granted that every individual is unique dit terent ferent from every every other kopd one who now lives or has hag lived tho the same is probably true for individuals of species other than man although our methods of observation are frequently inadequate to show this attempts to understand the causes and significance of organic diversity have been made ever since antiquity the problem seems to possess an irresistible esthetic appeal and biology owes its existence in part to this appeal |