ION, GENERAL CONCEPTIONS, SELF-CONSCIOUSNESS, MENTAL INDIVIDUALITY. It would be very difficult for any one with even much more knowledge than I possess, to determine how far animals exhibit any traces of these high mental powers. This difficulty arises from the impossibility of judging what passes through the mind of an animal; and again, the fact that writers differ to a great extent in the meaning which they attribute to the above terms, causes a further difficulty. If one may judge from various articles which have been published lately, the greatest stress seems to be laid on the supposed entire absence in animals of the power of abstraction, or of forming general concepts. But when a dog sees another dog at a distance, it is often clear that he perceives that it is a dog in the abstract; for when he gets nearer his whole manner suddenly changes, if the other dog be a friend. A recent writer remarks, that in all such cases it is a pure assumption to assert that the mental act is not essentially of the same nature in the animal as in man. If either refers what he perceives with his senses to a mental concept, then so do both. (44. Mr. Hookham, in a letter to Prof. Max Muller, in the 'Birmingham News,' May, 1873.) When I say to my terrier, in an eager voice (and I have made the trial many times), "Hi, hi, where is it?" she at once takes it as a sign that something is to be hunted, and generally first looks quickly all around, and then rushes into the nearest thicket, to scent for any game, but finding nothing, she looks up into any neighbouring tree for a squirrel. Now do not these actions clearly shew that she had in her mind a general idea or concept that some animal is to be discovered and hunted? It may be freely admitted that no animal is self-conscious, if by this term it is implied, that he reflects on such points, as whence he comes or whither he will go, or what is life and death, and so forth. But how can we feel sure that an old dog with an excellent memory and some power of imagination, as shewn by his dreams, never reflects on his past pleasures or pains in the chase? And this would be a form of self-consciousness. On the other hand, as Buchner (45. 'Conferences sur la Theorie Darwinienne,' French translat. 1869, p. 132.) has remarked, how little can the hardworked wife of a degraded Australian savage, who uses very few abstract words, and cannot count above four, exert her self-consciousness, or reflect on the nature of her own existence. It is generally admitted, that the higher animals possess memory, attention, association, and even some imagination and reason. If these powers, which differ much in different animals, are capable of improvement, there seems no great improbability in more complex faculties, such as the higher forms of abstraction, and selfconsciousness, etc., having been evolved through the development and combination of the simpler ones. It has been urged against the views here maintained that it is impossible to say at what point in the ascending scale animals become capable of abstraction, etc.; but who can say at what age this occurs in our young children? We see at least that such powers

https://www.jstage.jst.go.jp/article/ase1887/22/257/22_257_458/_pdf

The descent of man and selection in relation to sex

Female yellow-headed blackbirds in eastern Washington State settle to nest at higher densities on marshes with higher emergence rates of odonates, the most important prey delivered to nestlings. However, settling densities of females were not correlated with odonate emergence rates on individual territories or on individual territories plus adjacent ones. Apparently, females assessed production of insects on breeding marshes at the time they settled, and they used this information when making settling decisions. However, they selected nest sites on the basis of vegetation density rather than food availability. The complexity of decision making by female yellowheads would not have been detected had our analysis been restricted to one spatial scale. Because interpretations of habitat selection behavior are scale-dependent, careful attention to scale and performing analyses on more than one spatial scale are essential in studies of habitat selection. Habitat selection, an almost universal activity among animals, affects nearly all of an individual's subsequent choices. As a result, considerable attention has been paid to both the theory of habitat selection and the ways in which organisms in different taxa actually evaluate and select from the different options available (Cody 1985). A general guiding theoretical principle is that preferences among environments should coevolve with the qualities of those environments. That is, organisms should respond positively to (prefer) environments in which their sur- vival and reproductive success is good (Levins 1968; Orians 1980a). Individuals that elect to settle in less suitable environments leave fewer surviving offspring than those choosing better habitats. Whereas the logic of this general approach is compelling, correlations between habitat features and success may be low or difficult to assess in real-world situa- tions. A normally good environment may be poor because other factors (diseases, predators) reduce quality below expected levels or because resources are tempo- rarily depressed. Ease of assessment may depend on the grain of environmental patches in relation to the scale of exploitation by the organism (Levins 1968). Moreover, individuals may have difficulty in assessing the actual qualities of environments. This is especially true when the value of the habitat depends on its ability to provide resources for some time into the future. Some of these resources may not be present or evident at the time the decision must be made. In this article, we explore stages in the habitat-selection process and consider different spatial scales of decisions with the objective of providing a more compre- hensive way of viewing details of habitat-selection processes.

Spatial and Temporal Scales in Habitat Selection

Aim We reviewed the occurrence of Bergmann’s rule in birds (ninety-four species) and mammals (149 species), using only studies where statistical significance of the results was tested. We also tested whether studies using different characters as surrogates of body size have a different tendency to conform to Bergmann’s rule, whether body size and nest type (in birds) have an influence on the tendency to conform to the rule, and whether sedentary birds conform to the rule more than migratory birds. Location Worldwide. Methods We reviewed published data on geographic and temporal variation in body size, using only studies where the statistical significance of the results was tested. We asked how many species conform to the rule out of all species studied in each order and family. Results Over 72% of the birds and 65% of the mammal species follow Bergmann’s rule. An overall tendency to follow the rule occurs also within orders and families. Studies using body mass in mammals show the greatest tendency to adhere to Bergmann’s rule (linear measurements and dental measurements show a weaker tendency); while in birds, studies using body mass and other surrogates (linear measurements and egg size) show a similar tendency. Birds of different body mass categories exhibit a similar tendency to follow Bergmann’s rule, while in mammals the lower body size categories (4–50 and 50– 500 g) show a significantly lower tendency to conform to the rule. Sedentary birds tend to conform to Bergmann’s rule more than migratory species. Nest type does not affect the tendency to conform to Bergmann’s rule. Main conclusions Bergmann’s rule is a valid ecological generalization for birds and mammals.

/pdf/on-the-validity-of-bergmann-s-rule-sf29n9xsn5.pdf

On the validity of Bergmann's rule

Songs are complex acoustic signals produced mainly during the mating season. Such signals are found in many taxa but are most typical of birds, frogs, and insects. Darwin (38) noted that in these groups males are the predominant singers, and for this reason he attributed the evolution of song to sexual selection, that is, selection due to competition for mates. Darwin could muster no direct evidence that song or other display influences mating suc­ cess; only recently has such evidence begun to accumulate. Our fIrst goal here is to review and evaluate evidence that song influences mating success, via either female choice or male contests. Although convinced that sexual selection shapes display behavior, Darwin could not explain the evolution of a relationship between display and mating success. Fisher (50) first gave such an explanation in his discussion of female choice and male threat display. Our second goal is to review ideas and evidence on the evolution of relationships between song and female choice, and between song and success in male contests. We focus on the question of why listeners have evolved to respond to song in the contexts of female choice and male contest.

Sexual selection and the evolution of song

http://directory.umm.ac.id/Data%20Elmu/jurnal/S/Small%20Ruminant%20Research/Vol35.Issue3.Jun2000/1863.pdf

The physiological basis of adaptation in goats to harsh environments

In most species of birds adult males are larger than adult females. The two major hypotheses proposed to explain this pattern of sexual size dimorphism are appropriately termed the sexual selection and competition avoidance hypotheses. The sexual selection hypothesis states that large size gives males an advantage in intrasexual competition for females or in epigamic displays, activities not engaged in by females. Males will thus be larger than females, and the difference should be greater among polygynous and promiscuous species where there is greater variability in male reproductive success and thus stronger sexual selection (Darwin, 1871; Huxley, 1938; Fisher, 1958). The sexual selection hypothesis, then, explains the relationship between pronounced sexual dimorphism in size and nonmonogamous mating systems in birds (Darwin, 1871; Selander, 1958, 1972; Amadon, 1959; Orians, 1961), a relationship particularly evident among the Icteridae (Selander, 1958). The competition avoidance hypothesis states that sexual size dimorphism is favored because it reduces competition between males and females of the same species (Selander and Giller, 1963; Selander, 1966, 1972; Johnston and Selander, 1973). If size affects the range of resources used (e.g., larger individuals eat larger food items), then those males differing most in size from females would overlap in resource utilization with the fewest individuals and thus have the most resources available. This hypothesis may be especially applicable to monogamous, ter-

Sexual selection and body size in male red-winged blackbirds.

Male Characteristics and Pairing Success in Red-Winged Blackbirds

Optimum body sizes at different ambient temperatures: an energetics explanation of bergmann's rule

flyers. These birds could easily have been forced down at sea by a sudden squall or become exhausted fighting less severe but constant spring and fall winds. Once on the sea surface they were probably picked up at night by the tiger shark, which tends to be a crepuscular feeder and normally does not approach the surface by day (Springer, ibid.). The presence in the tiger shark of a Mourning Dove, a nonmigrant found adjacent to the beaches in this region, may be the result of this bird having been swept seaward by a strong offshore wind, or already dead, possibly swept out to sea from the adjacent estuary. We thank Dr. George Watson, curator, Division of Birds, United States National Museum and his assistant Mrs. Roxie C. Laybourne for assistance in bird identification. This is contribution No. 78 from the Harbor Branch Foundation Inc., Fort Pierce, Florida.--Received 8 August 1977, accepted 27 August 1977.

http://academic.oup.com/auk/article-pdf/95/3/586/32912240/auk0586.pdf

Foraging Success in Three Age Classes of Glaucous-Winged Gulls

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Sexual selection and body size in male red-winged blackbirds.

Male Characteristics and Pairing Success in Red-Winged Blackbirds

Optimum body sizes at different ambient temperatures: an energetics explanation of bergmann's rule

Foraging Success in Three Age Classes of Glaucous-Winged Gulls