Parasites (Continued) 

 as producers of disease: 

 bacteria, 181 

 fungi, 181 

 protozoa, 180-181 

 ticks, fleas, lice, mites and 



flies, 181 

 viruses, 181 

 worms, 180 

 causing food- poisoning, 181 

 classification of, 178-179 

 development of immunity to 



diseases carried by, 181-182 

 effects of accidental presence of 



in exotic host, 181-182 

 effects of lowering of host's 



resistance to, 181 

 endoparasites, evolution of, 179 

 evolution of varieties requiring 



intermediate hosts, 178 

 factors in transmission of, 228 

 free- living evolution of mto 



ectoparasites, 179 

 gall wasps as, 180 

 methods of transfer of from one 



host to another, 179 

 mutant strains of, 181 

 normalcy of presence of in healthy 



host, 181 

 restriction of to special niches in 



body, 180 

 role of in interspecific competi- 

 tion, 254 

 species of involved in social 



parasitism, 179 

 species of on animals, 178-179 

 species of on plants, 179 

 taxonomies of and phylogenetic 



relationships of hosts, 180 

 Parasitism (see a/so Parasites): 

 defined, 178 

 disease in, defined, 180 

 host- specificity in, 180 

 mutants in and host mortality, 228 

 nutritional deficiencies caused by, 



181 

 role of in physiological stress, 181 

 social, described, 179 

 Parasitoidism (see also Parasitism): 

 as example of carnivorous feeding, 



187 

 as factor in determining success 



with which prey species will 



compete for niche, 249 

 as parallel to predation in curtail- 

 ing over-population, 226 

 attempts at artificial control of 



pests and disorder in, 227 

 choice of larvae for egg- laying in 



determined by conditioning, 251 

 coactions in as affected by tem- 

 perature, 227 



Parasitoidism (Continued) 

 crop pest control through intro- 

 duction of, 227 

 differences of from parasitism, 



182 

 difficulty of finding host in and its 



consequent survival, 240 

 duplicate infestations in due to 



increase in parasitoids, 226-227 

 evaluating effect of on insect 



larvae, 230 

 hyperparasitoidism as form of, 182 

 importance of buffer species in, 



227 

 lack of random behavior in search 



for host in, 227 

 low host densities and reproductiv- 



ity in, 226-227 

 normal relation between host and 



parasitoid in, 226 

 parallelism of hyperparasitoidism 



to, 226 

 resemblances of to predation, 182 

 reversal of dominance in, 246 

 use of to control plagues, 234-235 

 Photosynthesis: 

 and amount of oxygen in water, 63- 



64 

 and carbon cycle, 167 

 and carbon dioxide in lakes, 65 

 and compensation point in sea, 354 

 and formation of energy for plant's 



activities, 201 

 and oxygen content of ponds, 79 

 and respiration approximately equal 



when trophic levels in balance, 



206-207 

 by lake organisms, 61 

 effect of curtailing of on fish, 87 

 efficiency of use of solar radiation 



in, 205 

 factors controlling rate of, 12 

 immediate initiation of as response 



to environment, 10 

 in food- cycle of lakes, 74 

 of algae in coral reef biome, 366 

 reduction of through heavy grazing, 



125-126 

 reduction of through sitting, 56 

 reproduction affected by light in, 



60, 60-61 

 role of in experiments to determine 



primary production of energy, 



203, 203-204 

 Physics, tropisms and taxes explain- 

 able in terms of, 12, 12-13 

 Physiological Adjustments (see also 



Adjustment(s) to Terrestrial 



Habitat(s)): 

 and law of the minimum, 12 

 and law of toleration, 10-11, 11-12 

 and threshold of organism, 10 



Physiological Adjustments (Continued) 

 as first response to environmental 



changes, 10 

 cycles in as correlated with popu- 

 lation cycles, 241-242 

 immunity to diseases as, 181-182 

 internal, for resistance to cold by 



forest animals, 299 

 made by sea organisms in fresh 



water, 96 

 to stress, 181 



types of in response to environ- 

 mental factors, 10 

 Physiological ecology, growth of as 



a branch of ecology, 6 

 Physiology: 

 as secondary consideration in 



ecological life history, 16 

 distribution of species according 



to, 27 

 of organism and initiation of major 



activity in life cycle, 14 

 relation of to ecology, 3 

 Plagues: 

 as providingfood for predators, 226 

 biological control of in United 



States, 234-235 

 defined in terms of untrained 



observers, 234 

 occurrence of niche segregation 



during, 253 

 of bean clams in California, 235 

 of field mice, through starting 



epizootics of mouse typhoid, 235 

 of locusts in tropics, 349-350 

 of rabbits through introduction of 



myxomatosis, 235 

 of small mammals in prairies, 329 

 of spruce budworm, 243, 309-310 

 outbreaks of since beginning of 



recorded history, 234 



synonymous terms for, 234 



Plankton (see also Sea, Oceanic 



Plankton and Nekton Biome): 

 absence of in winter in antarctic, 



319 

 abundance of in eutrophic lakes, 64 

 ancient origin of, 67 

 as food source for young fish, 75 

 as food source in ponds, 87 

 as reducers of light intensity in 



water, 172 

 as subjects of experiments in 



uses of energy, 206 

 biomass of in lakes, 75, 75-76 

 censusing of, 39-40 

 cyclomorphosis in, 60 

 daily migration of, 159 

 diel movements of, 67-68 

 distribution of in small and 



medium- sized lakes, 67 

 fecundity of, 210 



432 Index 



