ECOLOGICAL BACKGROUND AND GROWTH BEFORE 1900 



19 



The measurement of the evaporating 

 power of the air with a Piche evaporimeter 

 had been recorded in the Montsouris An- 

 niiaire for 1888. Knowledge of other effects 

 of wind is much older. The relation of wind 

 to the dispersion of spores had attracted at- 

 tention, and certain of the relations to vege- 

 tation were also known. For example, Woll- 

 ny (1891, vol. 14, p. 176) records that the 

 catch of living spores on suitable glass 

 plates in forests is about one-third of that 

 found in the open country. 



Interrelations between living organisms 

 were also being studied. Cordus, the Ger- 

 man herbalist, in his Historia Plantarum, 

 published posthumously in 1561, had de- 

 scribed the tubercles on lupine roots. It is a 

 far cry from this initial description to the 

 experiments on nitrogen fixation that flour- 

 ished in the 1880's. By the end of that 

 decade, much of the basis for present day 

 knowledge of the symbiotic functioning of 

 root tubercles had been experimentally out- 

 lined (see Abbe, 1905, p. 136 ff). 



It is perhaps pardonable to pause in the 

 midst of this historical survey to point out 

 a fact that is steadily becoming more and 

 more evident. When Brooks was writing the 

 passage referred to earlier in this chapter, 

 or when, to anticipate. Warming was study- 

 ing the vegetation of the Danish dunes in 

 the early 1890's, there already existed a 

 rich literature concerning the relations of 

 organisms to their environment. Having 

 made this point, it is unnecessary to trace 

 out each detailed advance. We do need to 

 turn to the zoological developments of the 

 nineteenth century to find how far general 

 knowledge about the environmental rela- 

 tions of animals had progressed by the end 

 of that period. 



The work of tracing the history of ecol- 

 ogy is made easier by the books of Daven- 

 port and Semper. Davenport brought to- 

 gether much ecological information in his 

 Experimental Morvholo^i/ (1897-1899, 2 

 vols., 508 pp.) and documented his writing 

 in modem st^'le. The excellent review by 

 Semper (1879 to 1881), called Animal 

 Life, covers a part of the same literature. 

 Both these men had a hand in the rise 

 of self-conscious ecology, a topic that will 

 be considered in due time. 



The advances in animal ecoloijv during 

 this period can be more soundlv evaluated 

 if the history of plant physiology is also 

 considered. This is summarized by Sachs 



(1882) and Pfeffer (1900-1906). The 

 more distinctly ecological discussion by 

 Klebs (1896) of the conditions of existence 

 as they affect the reproduction of algae and 

 fungi is also significant. 



It had been suggested before the 1890's 

 that respiration of anaerobic bacteria and 

 of other parasitic organisms resulted from 

 the breaking down of oxygen-containing 

 compounds present in the nutritive medium 

 (cf. Loew, 1891, p. 760). Much earlier, 

 Kiihne (1864) had shown experimentally 

 that protoplasmic movement in the ameba 

 is slowed down in the absence of oxygen, 

 while subsequently it was found that the 

 presence of increased amounts of carbon 

 dioxide immobilizes quickly, but kills slowly 

 (Demoor, 1894). 



The preliminary information concerning 

 acclimatization to poisons had been worked 

 out both with man (Binz and Schulz, 1879) 

 and other animals (Ehrlich, 1891). Obser- 

 vations on many organisms had yielded the 

 generalization that an organism which pro- 

 duces an albuminoid poison is resistant to 

 that poison. Thus Fayrer (1872) reported 

 that snakes were not killed by injections of 

 their own poison; modern studies show that 

 such immunity is only relative (Keegan 

 and Andrews, 1942). 



Determinations by Bezold as early as 

 1857 showed that the amount of water ordi- 

 narily present in body tissues varies with 

 different species. By 1896 it was known 

 that seeds do not germinate if they contain 

 only 10 to 15 per cent of water and that 

 certain animals can revive after being desic- 

 cated. Leeuwenhoek mentioned in a letter 

 written in 1702 that when dry stuff from a 

 gutter was put in water, organisms ap- 

 peared, and Hall (1922) states that Baker 

 in 1764 had revived nematodes after they 

 had been in a dried state for twenty-seven 

 years. Spallanzani, in the late eighteenth 

 century, similarly revived dried rotifers. 

 Preyer (1891) coined the modern term 

 "anabiosis" to apply to apparent death, and 

 Davenport believed (1897), but admittedly 

 could not prove, that anabiosis could re- 

 sult from acclimatization rather than selec- 

 tion. Semper (1881, p. 174) doubted whe- 

 ther, after the protoplasm was actually and 

 truly desiccated, revival could take place, 

 though he knew that eggs of the phyllopod 

 crustacean Aviis could be kept in mud for 

 vears and still hatch out if properlv mois- 

 tened. Other cases of recovery after ex- 



