Introduction To Diversity Of Life Notes PDF

Introduction to Diversity of Life There are about 1375500 living animals known, and at least 500000 extinct forms described \] A few hundred or so new species are described each year (nearly 17,000 new species published in 2007) \] The most common types of life on earth are beetles \] The inventory...

Introduction to Diversity of Life There are about 1375500 living animals known, and at least 500000 extinct forms described \] A few hundred or so new species are described each year (nearly 17,000 new species published in 2007) \] The most common types of life on earth are beetles \] The inventory of living animals is far from being complete \] 'Parade of living organisms': ± If one had to review each species at the rate of one species per second, there would be a continuous procession (12days 23hours) \] A way of showing the relative number of species in each major group is Quentin Wheeler's 'species-scape': \] In terms of number of species, mammals are not actually numerous. If living and extinct plants, fungi, bacteria etc. are added to the equation, the total number will increase to 2.3 million known species \] Estimates of the number of living organisms known and still awaiting discovery range from 3 to 10 million... \] Case Study: Terry Erwin's Estimate that there might be 33 million living species ± Terry Erwin fogged trees with insecticide to collect beetles in the Tambopata Reserve in Panama ± Species overlap between two plots only 50m apart was only 8.7% ± One species of tree, Luehea seemannii, yielded 163 species of beetles unique to its canopy \] Based on observation that beetles make up \~40% of all insects \] Why worry about how many species (and their loss)? ± In the words of Robert M. May: "We are astonishingly ignorant about how many species are alive on Earth today, and even more ignorant about how many we can lose yet still maintain ecosystem services that humanity ultimately depends upon."