prolonged effort she managed to stuff the caterpillar 

 back into place. She then collected a pellet of clay 

 and mended the hole. Such behavior as this involves 

 an apprehension of relations and a sudden adaptive 

 response not preceded by trial and error. Insight 

 learning may be manifested in various ways as 

 through homing ability, detouring around obstacles, 

 tool-using, discrimination of forms and patterns, and 

 so forth. 



Ecological life histories 



Developmental life histories trace the origin and 

 growth of structures and functions of an animal from 

 the egg stage until maturity is reached. Such studies 

 are largely embryological in nature. Behavior life 

 histories attempt to analyze the activities of animals 

 in terms of innate and learned behavior, and the 

 neural mechanisms involved. In order to do this, it 

 is often necessary to trace the origin of each activity 

 to the manner in which it first makes its appearance 

 in the young animal. Ecological life histories, on the 

 other hand, are concerned with the activities of a 

 species throughout its life cycle, and in relation to 

 its adjustments to natural conditions. Ecological life 

 histories usually proceed with, first, analysis of the 

 behavior adjustments needed for the survival of the 

 mature animal ; then of its reproductive behavior ; 

 and, lastly, of the development of behavior and physio- 

 logical adjustments of the young animal. In general, 

 the proper procedure is. . . to discover and estab- 

 lish correlations betiveen the behavior of the organism 

 and the conditions in its environment, and then to 

 test the significance of the correlations by appropriate 

 experiments in nature or in the laboratory. The point 

 should be emphasized that you start with nature, that 

 is, with the organism in its environment. Also it 

 should be noted that morphology and physiology of 

 the organism are entirely subsidiary matters, al- 

 though most important to the person interested in 

 knowing how the organism behaves as it does. . . 

 (Huntsman 1948). The behavior of a species in re- 

 lation to its environment is called its mores (Shelford 

 1913). 



The following are important items that should be 

 included in a complete ecological life history of a 

 species : 



1. Phylogenetic and geological history. 



2. Geographic and habitat distribution with an 



analysis of adjustments to the physical en- 

 vironment and of biotic interrelations within 

 the community. 



3. Variations in population, through time and 

 in space. 



4. Changes in seasonal activities and physiologi- 



cal states: breeding, migration, hibernation. 



5. Food, enemies. 



6. Parasites, diseases. 



7. Reproductive potential, mortality, rate of pop- 

 ulation turnover. 



8. Requirements for reproduction : home range, 

 territory, nest-site, nesting materials, etc. 



9. Breeding behavior : mating, nesting, etc. 



10. Development of offspring: rate, stages, gen- 

 erations per year, etc. 



Useful outlines, methods, and bibliographies for 

 ecological life history studies of different kinds of 

 animals and plants have been published in the scien- 

 tific periodical Ecology since October, 1949. 



Ecological niche 



The ecological niche is the particular position in 

 a community and habitat occupied by an animal as 

 the result of its peculiar structural adaptations, its 

 physiological adjustments, and the special behavior 

 patterns that have evolved to make best use of these 

 potentialities. Important factors in the niches occu- 

 pied by white-footed mice and deer mice are de- 

 scribed in Table 2-1. Both mice are equipped with 

 large eyes for nocturnal vision, large external ears 

 for hearing, long vibrissae on the face for aid in run- 

 ning through dark underground burrows, and pro- 

 tective coloration. P. I. novcboracensis has a longer 

 tail than P. m. bairdii. which appears to be an adap- 

 tation for climbing. It is possible that these two 

 species are segregated into different niches because 

 bairdii is more tolerant of extreme temperatures and 

 low moisture conditions, and hence is more prevalent 

 than novcboracensis in the exposed grassland habitat, 

 but is unable to displace novcboracensis within the 

 forest because of the latter's tree climbing ability. 



Every species has its own peculiar niche. No two 

 species can permanently occupy exactly the same 

 niche in the same locality. The living together of 

 many species in the same community is possible only 

 because their various niche requirements are differ- 

 ent. The analysis of the critical factors in these niche 

 requirements is often very dif^cult but is one of the 

 main objectives of ecology. 



COMMUNITY INTERRELATIONS 



The fact that species with similar tolerances 

 and requirements aggregate into similar environ- 

 ments to form communities is a response of special 

 interest. No organism occurs alone. Each must find 

 its place in the community and establish relations 

 with other members of it. The manner in which the 

 response of species to each other is affected is shown 

 in the structure and composition of the community 



Background 



