Title: Animal Life as affected by the Natural Conditions Of Existence 2nd Installation By: Karl Semper, Professor
of the University of Wurzburg Published by: D. Appleton and Company, Mew York, NY 1881 Verse and abstract by parvusvox@hotmail.com
Leopard Frog Origin Green skies over an evolution ‘proofer's laboratory again Karl Semper arrives examines about Looking determined and 'Darwinial the only 'Agassial part -- that species originating near icy silence where salted amphibian leopard frog awaits now mutant white species fade into green diversified beginnings then leopard frog again. The Author said this list, however , makes no pretension to completeness. If only it should give an impulse to research, on however small a scale, so long as it is systematically conducted and thoroughly carried through -- if only it should contribute to extend my own convictions as to the uselessness of casual and disconnected observations, I shall have attained my end. Next, let us look at one of his experiments. This is a fitting topic because of the threat to amphibians we face today. The effect of the different percentage of salt. If a green leopard frog absorbs more salt than it can bear, it will die, and its death will ensue all the sooner, the stronger the solution is in the first instance. also people dying thirst will expire if they drink sea salt water. It causes some sort of delirium. A great
number of frogs were placed in different vessels with splints straddling each frog to keep the frogs head above water. Each of the frog containers had the same quantity of water with various, but known, amounts of salt in solution -- By this he found that the frog commonly died, on an average, in about two hours and a half in a solution of five-per cent. of salt and not before more than twenty-four hours had elapsed in one and a half per cent. They all, without exception, endured a solution of one per cent. without sustaining any injury; that is to say, they lived as long in the very uncomfortable position -- K. Semper rigged up a way to keep the salty water from the frogs' nose and mouth since absorption of salty water through the frogs' skin was previously known and he was extending this prior knowledge towards his hypotheses as other frogs which were fastened up in the same way in pure fresh water--namely from three to four days--The later fresh-water ones were His 'control specimens for this experiment. He also limited the number of variables to just one variable, the saltiness of the water to garner His results. This shows me he was doing very rigorous scientific method to try to define what He said in the preface..all the hypotheses on variability and heredity still await intrinsic explanation. Out of the various and heated opinions of his day he felt that the topic of variability was the easiest one to trace back to its efficient causes. Next let us check his expanded note for his number 59 note on this frog experiment. It amazes me how with just a little set of initiatives enthusiastic people can scale the mount Everest’s of their aspirations -- According to Bernard's researches on the leopard green frog and Plateau's on tan Crustaceans, we might almost be tempted to suppose that all animals that migrate from the sea to rivers, and vice versa, the different degree of saltiness between their tissues and the surrounding water would be rapidly equalized by the osmotic action of the skin. In many creatures, as e.g., the Stickleback, this is no doubt the case--Though as of 1877 no conclusive experiments had been made even on this fish. This scientist's regimen was just one such example of many covered in Mr. Kemper's two volumes....
This is an important book, a quintessential scientific methods manual that serves as a centerpiece during the era when Agasisi and Darwin squared off against each other. Rex S. The Parvusvox Journal