THE PROCESSION OF LIFE THROUGH THE AGES

October 27, 2009 | Posted by maneerat

The Rock Record

How do we know when the various classes of animals and plants were established on the earth? How do we know the order of their appearance and the succession of their advances? The answer is: by reading the Rock Record. In the course of time the crust of the earth has been elevated into continents and depressed into ocean-troughs, and the surface of the land has been buckled up into mountain ranges and folded in gentler hills and valleys. The high places of the land have been weathered by air and water in many forms, and the results of the weathering have been borne away by rivers and seas, to be laid down again elsewhere as deposits which eventually formed sandstones, mudstones, and similar sedimentary rocks. Much of the material of the original crust has thus been broken down and worked up again many times over, and if the total thickness of the sedimentary rocks is added up it amounts, according to some geologists, to a total of 67 miles. In most cases, however, only a small part of this thickness is to be seen in one place, for the deposits were usually formed in limited areas at any one time.

Categories: THE OUTLINE OF SCIENCE | Tags: Air And Water, Amphibians, Animals And Plants, Continents, Crust Of The Earth, Devonian Period, Fossils, Geologist, Geologists, Hills And Valleys, Mountain Ranges, Plants And Animals, Procession, Sedimentary Rocks, Sediments, Strata, Succession, Troughs, Vicious Circle, Weathering | No Comments »

Is there Life on Mars?

October 22, 2009 | Posted by maneerat

The basis of this belief is that if, as we saw, all the globes in our solar system are masses of metal that are cooling down, the smaller will have cooled down before the larger, and will be further ahead in their development. Now Mars is very much smaller than the earth, and must have cooled at its surface millions of years before the earth did. Hence, if a story of life began on Mars at all, it began long before the story of life on the earth. We cannot guess what sort of life-forms would be evolved in a different world, but we can confidently say that they would tend toward increasing intelligence; and thus we are disposed to look for highly intelligent beings on Mars.

Categories: THE OUTLINE OF SCIENCE | Tags: Air And Water, Atmosphere Of Mars, Dark Fringe, Different World, Distance From The Sun, Fluid Water, Globes, Intelligent Beings, Life On Mars, Lifelong Study, Marshes, Martians, Percival Lowell, Pickering, Polar Caps, Polar Ocean, Sort Of Life, Straight Lines, Thin Sheets, Water Vapour | No Comments »